Matt, you can buy a set of sockets that grip capscrews or rounded bolts from the outside, Ebay https://www.ebay.co.uk/itm/SUPER-SA...h=item25952f2c6b:g:ZswAAOxyc2pTcNZw:rk:6:pf:0, or Snap on for a better, vastly more expensive kit.
A 2nd A2 for me - project FSI
- Thread starter BiggDogg
- Start date
BiggDogg
A2OC Donor
Thanks Bruno, that kit looks useful but I don't see how it will help with the Allen head (hex socket) cap screws holding the sump flange. The outsides are round.
BiggDogg
A2OC Donor
Thanks Tom. I’m slightly nervous of cracking the sump flange casting but might give that a go. The rubber band technique is cool, never saw that. (By the way I’ve still not found the starter solenoid wire, haven’t forgotten you want a connector photo though).
Matt
Sent from my iPhone using Tapatalk
Matt
Sent from my iPhone using Tapatalk
BiggDogg
A2OC Donor
Many thanks for all the suggestions.
All sump bolts now out, the first cat and flexi exhaust pipe section too, and the sump is stuck there just on its sealant ready for me to drop it off one evening this week, release the big end bearing caps and slide the pistons out, numbering them in turn.
The 7 rounded-off hex socket cap head bolts yielded after cutting slots using either a mini cutting disc in my Dremel or a 1mm cutting disc in a standard angle grinder depending on access, then using my wheelie gun fitted with the end off an impact driver and largest flat blade bit. The impact driver alone wouldn’t do it. Here’s photos of the 7 mullered bolts and where they came from. The one by the driveshaft cv joint was tricky and I’m glad the 2 closest to the flywheel came out ok in the first place because there is little chance I could have cut slots.
Sent from my iPhone using Tapatalk
All sump bolts now out, the first cat and flexi exhaust pipe section too, and the sump is stuck there just on its sealant ready for me to drop it off one evening this week, release the big end bearing caps and slide the pistons out, numbering them in turn.
The 7 rounded-off hex socket cap head bolts yielded after cutting slots using either a mini cutting disc in my Dremel or a 1mm cutting disc in a standard angle grinder depending on access, then using my wheelie gun fitted with the end off an impact driver and largest flat blade bit. The impact driver alone wouldn’t do it. Here’s photos of the 7 mullered bolts and where they came from. The one by the driveshaft cv joint was tricky and I’m glad the 2 closest to the flywheel came out ok in the first place because there is little chance I could have cut slots.
Sent from my iPhone using Tapatalk
Vorsprung durch Technik
A2OC Donor
Great update. I'm also a fsi owner and if you don't mind me asking, was there any wear between the valve guides and the valves themselves. Wear being when the valve is slightly pulled away from the valve seat and rocked side to side movement.Cheers Mark.
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BiggDogg
A2OC Donor
Mark,
I expect that there has to be some movement to allow for thermal expansion, I can feel some movement. I've not re-assembled the head yet. I am waiting to see if the block is a write off or not once I've got the pistons out and made various measurements then honed the bores. I'll check the manual to see if there is a standard way to measure the valve guide wear and report back, otherwise do you want to specify an opening distance - I have a dial gauge I can probably use to measure the side-play at the edge of the valve.
Matt
Vorsprung durch Technik
A2OC Donor
Yeah there's room for expansion but this is extremely small and something you wouldn't feel by hand. Just pull the valve out as far as it would extend in normal operating conditions. Can't say for sure never done this on an A2 but sormethink like 1/2 " or whatever the cam throw is. The movement should be almost imperceptible and if you can feel more than that indicates wear. That's my experience. I mentioned it to see what a typical A2 16 valve head shows in terms of valve guide wear on or about 95k. If you have a dial gauge that would accurately measure it and if you can obtain the permissible wear limit you will be able to see how much wear you have.
BiggDogg
A2OC Donor
The procedure is here:
https://workshop-manuals.com/audi/a..._valve_gear/valve_gear/checking_valve_guides/
The wear limit is 0.8mm with the valve stem end flush with the end of the valve guide so I'll go with that. Not sure what I'll do if it is worn past the limit. The drawing of the set-up for measurement shows a head which isn't an in-line 4-cylinder, maybe it is a VR6 head? I'll try and make some measurements tonight if I persuade myself it is too cold for lying under the car to pry the sump and remove the pistons.
https://workshop-manuals.com/audi/a..._valve_gear/valve_gear/checking_valve_guides/
The wear limit is 0.8mm with the valve stem end flush with the end of the valve guide so I'll go with that. Not sure what I'll do if it is worn past the limit. The drawing of the set-up for measurement shows a head which isn't an in-line 4-cylinder, maybe it is a VR6 head? I'll try and make some measurements tonight if I persuade myself it is too cold for lying under the car to pry the sump and remove the pistons.
BiggDogg
A2OC Donor
Mark,
Using the procedure linked above: my dial gauge can only measure the side-play on the 4 valves at either end due to its high profile but for the inlets it is ~0.26mm and for the exhausts ~0.48mm. The other 12 valves feel about the same, slightly better in the case of 2 of them, so I'm reasonably comfortable that they are all within the wear limit of 0.8mm.
I find it a bit odd that Audi say you can't replace the valve guides. I suspect that this is cobblers.
Matt
Using the procedure linked above: my dial gauge can only measure the side-play on the 4 valves at either end due to its high profile but for the inlets it is ~0.26mm and for the exhausts ~0.48mm. The other 12 valves feel about the same, slightly better in the case of 2 of them, so I'm reasonably comfortable that they are all within the wear limit of 0.8mm.
I find it a bit odd that Audi say you can't replace the valve guides. I suspect that this is cobblers.
Matt
Vorsprung durch Technik
A2OC Donor
Thanks for that Matt, that's very interesting and they don't seam to be worn too much at all.In the old days you could by manuals that would say what the new clearance would be and the wear limit so it would be interesting to know what the measurements would be when new? I have a new head here but no dial gauge. Perhaps it's time to invest in one at some point.Cheers Mark.
Vorsprung durch Technik
A2OC Donor
Thanks for that Matt that's a very kind offer that i may well take you up on. Cheers Mark.
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BiggDogg
A2OC Donor
Today's progress:
After undoing the bolt for the oil filler and the dipstick tubes assembly I discovered there are 2 more sump bolts adjacent to the flywheel, making a total of 20 plus the 2 large ones that screw into the bell housing. They are meant to be accessed with the special Audi tool T10058 that looks like a long Allen key with a ball end and takes a ratchet drive on the other. See here:
https://workshop-manuals.com/audi/a...rication_system/removing_and_installing_sump/
I don't have one of those so had to make do with what I had, a 1/4" square drive 1/4" hex socket driving a hex bit fitted with a 1/4" extension. This was a right fiddle to fit as the screws are offset back towards the flywheel vs the ~5" deep access holes in the sump casting but it JUST possible without the correct tool, thankfully both these bolts came undone easily and felt like they had only been done up to 10-15Nm compared to the other 18 which felt like some turkey had done them up to about 50Nm, probably why 7 of them rounded. The sump came off easily, there are places to pry at the corners.
Inside, initially all looked good. I undid the 4 big-end bearing caps using a clean 12-point 10mm socket, used a centre punch to identify them. TWO OF THEM HAD BEEN FITTED THE WRONG WAY AROUND. If you look here at the first diagram:
https://workshop-manuals.com/audi/a...nd_conrods/pistons_and_conrods_exploded_view/
...the features marked B faced the flywheel on 2 pistons. It looks like whoever has been in here before didn't know about this, instead they had lined up the 2D barcode and number etched or laser-printed on the outside to be the same way round for all 4 caps; however there doesn't seem to be any harm done, the bearing shells and crank journals all look OK. I pushed all the pistons up and out of the top of the block and inpected each.
Numbers 1, 2 and 4 have round about the same amount of scuffing on them as appears on the bores. The rings look OK in these cylinders, none was stuck in its groove. Number 3 is a different matter. On number 3, the 2nd ring down is in 2 pieces which explains the lack of compression and the leak-down to the crank case. The wear on the rear side is pronounced and I suspect that this piston may be scrap, I will check its dimensions but from a first inspection I'd have thought it will slap if I attempt re-use; hence I'm in the market for a single piston or a set of 4 for a BAD engine. I've put the sump back on with 2 bolts to keep dirt from entering and also re-applied WD40 to the deck and bores, covering the top of the deck with a couple of paper towels then a bin liner weighed down. Pictures of the bottom end, pistons being pushed out and the bores follow. I didn't get the chance to take piston pics yet, hopefully tomorrow when I plan to do some measurements and try honing.
Matt
After undoing the bolt for the oil filler and the dipstick tubes assembly I discovered there are 2 more sump bolts adjacent to the flywheel, making a total of 20 plus the 2 large ones that screw into the bell housing. They are meant to be accessed with the special Audi tool T10058 that looks like a long Allen key with a ball end and takes a ratchet drive on the other. See here:
https://workshop-manuals.com/audi/a...rication_system/removing_and_installing_sump/
I don't have one of those so had to make do with what I had, a 1/4" square drive 1/4" hex socket driving a hex bit fitted with a 1/4" extension. This was a right fiddle to fit as the screws are offset back towards the flywheel vs the ~5" deep access holes in the sump casting but it JUST possible without the correct tool, thankfully both these bolts came undone easily and felt like they had only been done up to 10-15Nm compared to the other 18 which felt like some turkey had done them up to about 50Nm, probably why 7 of them rounded. The sump came off easily, there are places to pry at the corners.
Inside, initially all looked good. I undid the 4 big-end bearing caps using a clean 12-point 10mm socket, used a centre punch to identify them. TWO OF THEM HAD BEEN FITTED THE WRONG WAY AROUND. If you look here at the first diagram:
https://workshop-manuals.com/audi/a...nd_conrods/pistons_and_conrods_exploded_view/
...the features marked B faced the flywheel on 2 pistons. It looks like whoever has been in here before didn't know about this, instead they had lined up the 2D barcode and number etched or laser-printed on the outside to be the same way round for all 4 caps; however there doesn't seem to be any harm done, the bearing shells and crank journals all look OK. I pushed all the pistons up and out of the top of the block and inpected each.
Numbers 1, 2 and 4 have round about the same amount of scuffing on them as appears on the bores. The rings look OK in these cylinders, none was stuck in its groove. Number 3 is a different matter. On number 3, the 2nd ring down is in 2 pieces which explains the lack of compression and the leak-down to the crank case. The wear on the rear side is pronounced and I suspect that this piston may be scrap, I will check its dimensions but from a first inspection I'd have thought it will slap if I attempt re-use; hence I'm in the market for a single piston or a set of 4 for a BAD engine. I've put the sump back on with 2 bolts to keep dirt from entering and also re-applied WD40 to the deck and bores, covering the top of the deck with a couple of paper towels then a bin liner weighed down. Pictures of the bottom end, pistons being pushed out and the bores follow. I didn't get the chance to take piston pics yet, hopefully tomorrow when I plan to do some measurements and try honing.
Matt
BiggDogg
A2OC Donor
Here's picture of the pistons. The order left to right is 4321 with flywheel on the left, and this is looking at the back of the pistons (the worst side).
The nominal dimension in the workshop manual is 76.475mm measuring the diameter 12mm up the skirt from the bottom edge. The maximum wear allowed is 0.040mm so the minimum diameter allowed is 76.435mm
I measure:
1: 76.45mm OK
2: 76.44mm OK
3: 76.42mm undersize - it's also a different colour and missing the 2nd compression ring
4: 76.45mm OK
I still have to measure hone and re-measure the bores so I'm not ordering anything yet. A brand new piston with rings is 036107065BN and is about £87 delivered on eBay.
The nominal dimension in the workshop manual is 76.475mm measuring the diameter 12mm up the skirt from the bottom edge. The maximum wear allowed is 0.040mm so the minimum diameter allowed is 76.435mm
I measure:
1: 76.45mm OK
2: 76.44mm OK
3: 76.42mm undersize - it's also a different colour and missing the 2nd compression ring
4: 76.45mm OK
I still have to measure hone and re-measure the bores so I'm not ordering anything yet. A brand new piston with rings is 036107065BN and is about £87 delivered on eBay.
BiggDogg
A2OC Donor
I took the remaining ring off the scrap piston and used it to check the wear on the cylinders by using feeler blades in the gap (after squaring the ring in the bore using the piston upside-down). I did this at the top, middle and bottom of each bore. All were OK. Of course, if they had been out of spec. I would have tried it with a new ring or an internal dial gauge (which I don't own). There is the possibility that the bores are oval, but I think it's unlikely given the wear on the pistons which are aluminium and softer than the cast iron block.
So, honing was next. Importantly, my crankshaft is still in the engine, which is still in the car. What I really didn't want was to contaminate the bottom end with anything, (since the honing stones shed abrasive material) and I experimented with cut-down PVC drinks bottles and gaffer tape placed at the bottom of the bores as catch tanks, but in the end I took my mechanic chum's advice and just used lots of clean blue paper towel (eek) stuffed on top of the crank, especially at the side-webs above the main bearings. This I topped off with some circles of cardboard cut from orange juice cartons and other packets from the recycling, just so as to lower the likelihood of snagging the blue towel if I accidentally went too deep with the honing tool.
I decided to not aim to completely remove the scuffing and only carry on until I really couldn't tell when my fingernail was going across the scuffed area. I used a 3-arm honing tool in an electric drill at 400-800rpm to start with, then much slower and bobbing the drill up and down as fast as I could at both speeds. It took 5-10 minutes per bore. I used penetrating oil as a lubricant, sprayed onto the stones. Every 50 or so bobs up and down, I pulled the tool out, dipped the stones in a bucket of water and spun the drill, then pulled it out, shook the water off and re-applied penetrating oil. This is the same method and tool as used in this YouTube clip:
Here are cylinders 2 and 4 on the top/bottom (not done) and cylinder 3 in the middle (done). The colour change from yellowy to grey did occur, but is amplified here by the choice of foil-backed OJ carton vs. cardboard to top-off the blue towel.
The weather deteriorated and I haven't re-checked the bore measurements with the ring, but I bet they are fine.
Next I changed the valve stem oil seals and refitted the valves, springs and collets. This went smoothly - the collets are a fiddle and I used grease to stick them in place temporarily whilst releasing the valve spring compressor. The workshop manual has some ridiculously complex method of changing oil seals which I think assumes the head is still on the block. I ignored this completely and just used plenty of oil to try to avoid damaging the oil seals' lips with any sharp corners on the ends of the valves or the collet grooves. Here is a pic of the job half done:
As a diversion I took apart the throttle body which had been making some clicking noises - I wiped the potentiometer tracks with IPA and gave the rubber seal a clean but couldn't find anything wrong so re-assembled it.
'Til next time.
Matt
So, honing was next. Importantly, my crankshaft is still in the engine, which is still in the car. What I really didn't want was to contaminate the bottom end with anything, (since the honing stones shed abrasive material) and I experimented with cut-down PVC drinks bottles and gaffer tape placed at the bottom of the bores as catch tanks, but in the end I took my mechanic chum's advice and just used lots of clean blue paper towel (eek) stuffed on top of the crank, especially at the side-webs above the main bearings. This I topped off with some circles of cardboard cut from orange juice cartons and other packets from the recycling, just so as to lower the likelihood of snagging the blue towel if I accidentally went too deep with the honing tool.
I decided to not aim to completely remove the scuffing and only carry on until I really couldn't tell when my fingernail was going across the scuffed area. I used a 3-arm honing tool in an electric drill at 400-800rpm to start with, then much slower and bobbing the drill up and down as fast as I could at both speeds. It took 5-10 minutes per bore. I used penetrating oil as a lubricant, sprayed onto the stones. Every 50 or so bobs up and down, I pulled the tool out, dipped the stones in a bucket of water and spun the drill, then pulled it out, shook the water off and re-applied penetrating oil. This is the same method and tool as used in this YouTube clip:
Here are cylinders 2 and 4 on the top/bottom (not done) and cylinder 3 in the middle (done). The colour change from yellowy to grey did occur, but is amplified here by the choice of foil-backed OJ carton vs. cardboard to top-off the blue towel.
The weather deteriorated and I haven't re-checked the bore measurements with the ring, but I bet they are fine.
Next I changed the valve stem oil seals and refitted the valves, springs and collets. This went smoothly - the collets are a fiddle and I used grease to stick them in place temporarily whilst releasing the valve spring compressor. The workshop manual has some ridiculously complex method of changing oil seals which I think assumes the head is still on the block. I ignored this completely and just used plenty of oil to try to avoid damaging the oil seals' lips with any sharp corners on the ends of the valves or the collet grooves. Here is a pic of the job half done:
As a diversion I took apart the throttle body which had been making some clicking noises - I wiped the potentiometer tracks with IPA and gave the rubber seal a clean but couldn't find anything wrong so re-assembled it.
'Til next time.
Matt
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BiggDogg
A2OC Donor
It's been too long since my last update, so here goes:
I bought a new piston which comes fitted with a set of new rings. I took it and the old one into work to get the gudgeon pin out and conrod off the old one then fit to the new one over a lunchtime. A funny thing happened - a great big lump of the side wall of the old piston fell off on the bench! The break-line is very durty with carbon so it had been running like this. It more fully explains the lack of compression and leak-down test failure. Going back to the photo in post # 77 you can actually see the crack in the second piston from the left, on its right hand side between the 2 compression rings. The old conrod fitted fine with assembly lube into the new piston.
The bores measured fine after honing, re-fitting the pistons was easy following a Youtube video or 2 and using a Laser ring compressor and more Lucas assembly lube. I used a set of new big end cap screws and torqued them up, even more assembly lube on the crank and big-end shells.
A note about the shells: Be really careful if this is your first stripdown of an engine: Bearing shells are very soft and easily damaged. Always bag them individually and take other precautions to stop them bashing into other parts like the big-end shells. If any are scored or worn (use Plastigauge to check) then get new shells. Mine were OK. Be sure to put them back in the same position and the same way around as they were fitted before. On this engine it is possible to fit the shells either way around. If you forget then the little audi oooo symbol and part number on the back may well have left a witness mark inside the conrod or big end shell housing and this can let you know how to orient it provided you weren't over-enthusiasitic with cleaning
.
I cleaned the sump with lots of paraffin both inside and out, blew it dry and grit free with my air-duster at 90psi and repeated. Then I washed it twice with soap and water and repeated the air treatment to be sure none of the grit from the outside was left inside, (not that I had been slapdash about transferring it). Then I cleaned up the mating flange at the base of the crankcase being scrupulous about wiping from inside to outside, this despite having used my pressure washer and detergent on the engine before starting (there was still a lot of filth around).
I pump the sump back on with a new set of bolts, correct grey silicone sealant (Reinzozil or something) in a 2mm bead and torqued the new bolts to 13Nm. There was a disaster with one of the 2 bolts by the flywheel when the 5mm hex ball-end bit caught on something, slipped out and fell behind they flywheel inside the bell housing. It is at times like those I tend to give up for the evening, come in from the cold and swear at myself for taking short cuts.
After some head scratching I could see only 2 ways out:
I chose (2). Perhaps now you'll understand why it's been a while since my last update.
I bought a new LuK clutch kit from GSF. I think it was £92 delivered the next day to work and it came with a new release bearing, sleeve and release arm. Of course, this could still be a waste of cash but I'm gaining a little confidence now...perhaps too much but we'll see.
Last week I fitted the clutch over 3 or 4 evenings. Of course I followed the workshop manual method largely but to gain decent spannering access I moved the water spout for the bonnet trumpet and thermostat housing to the front after releasing the electrical connections and all the tubes at the back and the ones that were too short to allow enough movement. This is a good first step and allows a lot of time to be saved when remving the gearbox control cables, clutch slave cylinder, starter motor etc. I split the left-hand lower ball joint taper using the Ed China method with a hammer after my scissor-tool failed to get in the gap between the top of the screw thread and the outer cv joint metal cup. It is the first time this method has worked for me. (After that I had planned to take my angle grinder to the scissor tool...). This car has the cast/forged wishbones so the ball-joint can't be unbolted separately as with the rust-prone pressed steel wishbones fitted to my TDI90 and all later cars.
The inside the clutch housing was surprisingly filthy and had signs of corrosion from water / salt ingress too. The old (Valeo) clutch had its friction material worn down a good deal but the whole thing absolutely stank of burnt clutch and there was loads of dust from the friction plate inside the flywheel too. I took over an hour to clean up everything inside the bell housing and fit new parts, lubricating the pivot points on the release arm and bearing with tiny dabs of moly grease, the same on the sleeve. I fitted the new clutch housing /pressure plate really carefully onto the flywheel. I aligned the friction plate with the centre of the flywheel by eye. Various moe reliable methods are no doubt available but this method has always worked for me,. This you can do from a few angles and its worth spending 5 minutes with a good head-torch but you may get stinky moly grease from the tied-up end of the left driveshaft in your hair if you're not careful. Moly grease always smells like a gas leak in our house.
I was very anal about doing only half a turn on each of the 6 screws in a diagonal rotating pattern so as not to distort the diaphragm spring too much and result in clutch judder. These screws are a 9mm 12 point external sline and an ordinary 12-point socket works a treat. I torqued them to spec. You don't really need to lock the flywheel to do this if you hold the torque wrench so it is tangential to the flywheel and moves inside the circle so your hand is pushing to the centre of the crank.
So, currently the gearbox is back on the car and torqued up. The engine and gearbox is sat on two trolley jacks with the right hand wheel on a ramp and the left of the car on an axle stand at the jacking point. I need to put the new death pipe back on and secure the thermostat housing in place so I can put the inlet manifold lower and upper parts on whilst the engine is still dropped down a little. I was wondering about that and feeling a bit dodgy in the heat yesterday so thought I'd tackle something easier. I changed the oil filter and pulled out the oil filler and dipstick tubes and front oil filler arrangement. I saw that the dipstick tube had broken at the bottom. Initially I thought that a trip to the dealer was going to be in order but then realised if I was careful with the length, there is a way to replace the plastic dipstick tube with rubber heater pipe. This I did. There is a possibility that it will rot but this is proper SAE heater pipe and should be OK in contact with oil. It will only get oil on it when taking the dipstick out of course...
Everything was black with gritty oily sludge so I set to and cleaned it all up with paraffin and multiple air blasting then washing, swapping from outside to inside once the outside was like new. I will only refit it once all the engine and gearbox mountings are back in. For now there is a bit of gorilla tape over the holes in the sump. I will get a pair of the green o-rings from Audi.
So, feeling OK by this point, I thought I;d get back to the main task...except I've lost that f***ing plastic C-clip that holds the death pipe to the thermostat housing... which is where I left it last night...
I've made this job excessively complicated by deciding to change the clutch in the middle of it. I realise that. But I still think it was the right decision. I am going to remove all the remaining hoses from the thermostat housing before bolting it back onto the end of the cylinder head so that I have some compromised access for spannering to reattach the clutch slave, gearbox cable brackets and other gubbins after refitting the inlet manifolds then the gearbox upper mounting.
Whilst searching through some parts I (at last) found the connector for my CAYC starter on the TDI90 with MYP gearbox. This is something I had been meaning to send photos of to @t42 Tom. For the moment we are both running round in our TDIs with bodged crimps on the solenoid wire...
I still have a list of jobs to do that runs to 2 sides of A4 on project FSI and that's before I turn the key.... starting to have fun again and lovely to have encouragement from the family "why don't you you give up on those bangers, why can;t we get a Tesla? etc."
Some photos next time, I promise.
All the best,
Matt
I bought a new piston which comes fitted with a set of new rings. I took it and the old one into work to get the gudgeon pin out and conrod off the old one then fit to the new one over a lunchtime. A funny thing happened - a great big lump of the side wall of the old piston fell off on the bench! The break-line is very durty with carbon so it had been running like this. It more fully explains the lack of compression and leak-down test failure. Going back to the photo in post # 77 you can actually see the crack in the second piston from the left, on its right hand side between the 2 compression rings. The old conrod fitted fine with assembly lube into the new piston.
The bores measured fine after honing, re-fitting the pistons was easy following a Youtube video or 2 and using a Laser ring compressor and more Lucas assembly lube. I used a set of new big end cap screws and torqued them up, even more assembly lube on the crank and big-end shells.
A note about the shells: Be really careful if this is your first stripdown of an engine: Bearing shells are very soft and easily damaged. Always bag them individually and take other precautions to stop them bashing into other parts like the big-end shells. If any are scored or worn (use Plastigauge to check) then get new shells. Mine were OK. Be sure to put them back in the same position and the same way around as they were fitted before. On this engine it is possible to fit the shells either way around. If you forget then the little audi oooo symbol and part number on the back may well have left a witness mark inside the conrod or big end shell housing and this can let you know how to orient it provided you weren't over-enthusiasitic with cleaning
. I cleaned the sump with lots of paraffin both inside and out, blew it dry and grit free with my air-duster at 90psi and repeated. Then I washed it twice with soap and water and repeated the air treatment to be sure none of the grit from the outside was left inside, (not that I had been slapdash about transferring it). Then I cleaned up the mating flange at the base of the crankcase being scrupulous about wiping from inside to outside, this despite having used my pressure washer and detergent on the engine before starting (there was still a lot of filth around).
I pump the sump back on with a new set of bolts, correct grey silicone sealant (Reinzozil or something) in a 2mm bead and torqued the new bolts to 13Nm. There was a disaster with one of the 2 bolts by the flywheel when the 5mm hex ball-end bit caught on something, slipped out and fell behind they flywheel inside the bell housing. It is at times like those I tend to give up for the evening, come in from the cold and swear at myself for taking short cuts.
After some head scratching I could see only 2 ways out:
- Release the engine-bell housing bolts and move the engine block away just enough to retrieve the hex-bit then do everything back up. A big risk in doing this would be accidentally bending the input shaft on the gearbox as the engine block would be supported only by a trolley jack under the sump...
- Treat getting the cylinder head and camshaft housing back on as a priority and the engine essentially dirt-tight, put the timing belt and right hand engine mounting back on, then take the gearbox out, retrieve the hex bit and fit a new clutch at the same time.
I chose (2). Perhaps now you'll understand why it's been a while since my last update.
I bought a new LuK clutch kit from GSF. I think it was £92 delivered the next day to work and it came with a new release bearing, sleeve and release arm. Of course, this could still be a waste of cash but I'm gaining a little confidence now...perhaps too much but we'll see.
Last week I fitted the clutch over 3 or 4 evenings. Of course I followed the workshop manual method largely but to gain decent spannering access I moved the water spout for the bonnet trumpet and thermostat housing to the front after releasing the electrical connections and all the tubes at the back and the ones that were too short to allow enough movement. This is a good first step and allows a lot of time to be saved when remving the gearbox control cables, clutch slave cylinder, starter motor etc. I split the left-hand lower ball joint taper using the Ed China method with a hammer after my scissor-tool failed to get in the gap between the top of the screw thread and the outer cv joint metal cup. It is the first time this method has worked for me. (After that I had planned to take my angle grinder to the scissor tool...). This car has the cast/forged wishbones so the ball-joint can't be unbolted separately as with the rust-prone pressed steel wishbones fitted to my TDI90 and all later cars.
The inside the clutch housing was surprisingly filthy and had signs of corrosion from water / salt ingress too. The old (Valeo) clutch had its friction material worn down a good deal but the whole thing absolutely stank of burnt clutch and there was loads of dust from the friction plate inside the flywheel too. I took over an hour to clean up everything inside the bell housing and fit new parts, lubricating the pivot points on the release arm and bearing with tiny dabs of moly grease, the same on the sleeve. I fitted the new clutch housing /pressure plate really carefully onto the flywheel. I aligned the friction plate with the centre of the flywheel by eye. Various moe reliable methods are no doubt available but this method has always worked for me,. This you can do from a few angles and its worth spending 5 minutes with a good head-torch but you may get stinky moly grease from the tied-up end of the left driveshaft in your hair if you're not careful. Moly grease always smells like a gas leak in our house.
I was very anal about doing only half a turn on each of the 6 screws in a diagonal rotating pattern so as not to distort the diaphragm spring too much and result in clutch judder. These screws are a 9mm 12 point external sline and an ordinary 12-point socket works a treat. I torqued them to spec. You don't really need to lock the flywheel to do this if you hold the torque wrench so it is tangential to the flywheel and moves inside the circle so your hand is pushing to the centre of the crank.
So, currently the gearbox is back on the car and torqued up. The engine and gearbox is sat on two trolley jacks with the right hand wheel on a ramp and the left of the car on an axle stand at the jacking point. I need to put the new death pipe back on and secure the thermostat housing in place so I can put the inlet manifold lower and upper parts on whilst the engine is still dropped down a little. I was wondering about that and feeling a bit dodgy in the heat yesterday so thought I'd tackle something easier. I changed the oil filter and pulled out the oil filler and dipstick tubes and front oil filler arrangement. I saw that the dipstick tube had broken at the bottom. Initially I thought that a trip to the dealer was going to be in order but then realised if I was careful with the length, there is a way to replace the plastic dipstick tube with rubber heater pipe. This I did. There is a possibility that it will rot but this is proper SAE heater pipe and should be OK in contact with oil. It will only get oil on it when taking the dipstick out of course...
Everything was black with gritty oily sludge so I set to and cleaned it all up with paraffin and multiple air blasting then washing, swapping from outside to inside once the outside was like new. I will only refit it once all the engine and gearbox mountings are back in. For now there is a bit of gorilla tape over the holes in the sump. I will get a pair of the green o-rings from Audi.
So, feeling OK by this point, I thought I;d get back to the main task...except I've lost that f***ing plastic C-clip that holds the death pipe to the thermostat housing... which is where I left it last night...
I've made this job excessively complicated by deciding to change the clutch in the middle of it. I realise that. But I still think it was the right decision. I am going to remove all the remaining hoses from the thermostat housing before bolting it back onto the end of the cylinder head so that I have some compromised access for spannering to reattach the clutch slave, gearbox cable brackets and other gubbins after refitting the inlet manifolds then the gearbox upper mounting.
Whilst searching through some parts I (at last) found the connector for my CAYC starter on the TDI90 with MYP gearbox. This is something I had been meaning to send photos of to @t42 Tom. For the moment we are both running round in our TDIs with bodged crimps on the solenoid wire...
I still have a list of jobs to do that runs to 2 sides of A4 on project FSI and that's before I turn the key.... starting to have fun again and lovely to have encouragement from the family "why don't you you give up on those bangers, why can;t we get a Tesla? etc."
Some photos next time, I promise.
All the best,
Matt
BiggDogg
A2OC Donor
My new C clip arrived so I refitted the death pipe with a smear of silicone grease on the rubber seals. Next comes the injectors then the lower intake manifold. When I took the injectors out (for the 2nd time), the brass collars all stayed attached to them and so I thought before I put them back I better take a look at the o-rings that I renewed when I did the job the first time. Well, I got a shock as seen in this photo. I can't tell from the diagrams in 7zap.com whether I put the o-rings in the right place or not. Certainly no petrol was leaking when I started up after the initial re-assembly, so it is possible that these o-rings have kinked up when I pulled them off this morning. There are meant to be 12 in all, 3 on each injector / collar. Can anyone tell me if I've got this right:
It is possible that the o-ring I put inside the collar should have gone on the outside of the collar in the little groove. I'll have to check the workshop manual and also see if I have any photos. Here are some more photos as promised too, more of relevance to the last post - I'm wondering if this engine seized, maybe when the death pipe went, then someone un-seized it with a hammer and didn't realise they'd broken a piston ring and a piston in the process.
Many thanks for any advice on the o-rings. Whilst on the subject, I'm also looking to replace the oil filler/dipstick tube assembly o-rings where they go into the engine block, but there's no part number or spec on these on 7zap.com . Any ideas?
Matt
- 1 o-ring goes on the injector (they all stayed in the right place)
- 1 o-ring goes inside the collar (3 of 4 kinked up or broken)
- 1 o-ring goes on the outside of the collar, on the manifold side of the split plastic ring (all stayed in the right place)
It is possible that the o-ring I put inside the collar should have gone on the outside of the collar in the little groove. I'll have to check the workshop manual and also see if I have any photos. Here are some more photos as promised too, more of relevance to the last post - I'm wondering if this engine seized, maybe when the death pipe went, then someone un-seized it with a hammer and didn't realise they'd broken a piston ring and a piston in the process.
Many thanks for any advice on the o-rings. Whilst on the subject, I'm also looking to replace the oil filler/dipstick tube assembly o-rings where they go into the engine block, but there's no part number or spec on these on 7zap.com . Any ideas?
Matt