K-Seal or Holts Wondarweld?

asrj52

Member
I know I'm very likely to hear people telling me to avoid using either of these products, but in the situation I'm in I really have nowhere else to go.

The engine in question is a TDI 1.4 (75) and thanks to the help of some good people on this forum the diagnosis is that I have a pinhole in the head gasket or a tiny crack in the block.

The problem is not yet severe. I can drive all day at 50mph with no problem apart from loss of coolant. The engine only overheats when I hit 60mph. There is no emulsion in the oil, nor any sign of any leaks. Can't see any steam from the exhaust either but I'm losing coolant at the rate of half a litre per 100 miles.

The thing is, as much as I love the car, cosmetically it's as rough as old boots and just not worth the heavy cost of a head repair. My plan therefore is to keep the engine going as long as possible. When it finally gives up on me I'll be looking for another A2.

In the meantime I suppose some sort of head sealant is my best option and I was wondering if anyone on here has experience of this type of product with the TDI engine.

K-Seal is certainly the easier option as it will mix freely with antifreeze/coolant and therefore does not require flushing out the cooling system before use.

Wondarweld can only be mixed with water which means the cooling system has to be flushed through twice (before and after application).

K-Seal is cheaper too so would be my preferred option unless I hear from someone with experience that Wondarweld is a markedly better product.

I know it's a shame that I find myself in this predicament but them's the breaks! Wish me luck.
 

Howey

Member
Used k seal for a badly leaking heater matrix on a passat, worked fantastically and wouldn't hesitate to use again!
However steel seal my be more appropriate for your application, wish you the very best with this, really hope you get a positive outcome!
 

audifan

A2OC Donor
As you have already said, the recommendation from us is to fix the issue properly. How long have you had the car and how long has it had this problem? What coolant are you running and has anything previously been added to the oil / coolant?

All said it is your car and your choice. Go for K Seal. But be aware it is a bit like using the tyre repair kit - nobody will want to work on it afterwards and obviously if you sell like this declare what has been done so the next owner isn't.
 

asrj52

Member
In answer to audifan's question - I bought the car 3 months ago - £600 and no service history - so always knew it was a gamble. I gave it a really good (1hr) test drive and checked for any obvious faults before parting with my money but the test drive was inner city so I never got it up to motorway speeds. The problem presented a week after the purchase the first time I hit the motorway. Since then I've done about 2000 low speed miles, one eye permanently on the temp gauge and topping up coolant before every journey.

Despite the problem I love the character and the utility of the car. If it was a pristine example I wouldn't hesitate to get it properly repaired.

As things stand however I think my only option is to keep it going as long as possible and when it does expire, sell it on as a spares car. Btw when the thermostat was changed the mechanic said there was a lot of 'gloop' attached to it. I suspect the former owner had previously used sealant and was aware there was a hidden problem. I would not do the same to another person.

My son has an expression that pretty much describes the state of play - 'Drive it until you kill it.'

Hopefully a K-Seal treatment will put off that final demise for sometime yet.
 

audifan

A2OC Donor
Before you go for the K Seal flush everything out as much as possible. Remove the thermostat to give better flushing. What colour was the coolant? It must be red / pink or violet. If it was blue or green that has probably done the damage to the engine.

Wouldn't go as far to drive it until you kill it, you already realise what good cars these are.

I would also have a full VCDS scan done on the car to see what other nice surprises may be lurking waiting to shake you firmly by the wallet.

I think a full service with correct parts and a cam belt and water pump change are imminent.
 

A2Dreamer

Member
I sceptically tried steel seal on a combustion chamber to waterway head gasket failure (renault 1.5 dci)

Needless to say, I wasn't disappointed... it didn't work! Sorry!

I can see it could work on a radiator or heater matrix, or possibly oil to water way on the head gasket, but not the combustion chamber I'm afraid.

Fingers crossed though, you've nothing to lose bar a few quid in giving it a try, just don't hang your hopes on it....
 

spike

Member
Audi warn against using radiator sealing products on cars with Webasto heaters presumably because it can block the internals.
Something to consider if you currently have a working Webasto

Also, as A2Dreamer indicated, they may work in sealing a radiator core where the coolant pressure is around 15 psi but may not cope with combustion pressures from a leaking head gasket

Cheers Spike

PS. Sorry, Just noted A2Dreamer said exactly the same thing in the previous post. Not my style to copy original ideas. Either that or maybe a case of great minds thinking alike
 
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GTSpec

Member
I sceptically tried steel seal on a combustion chamber to waterway head gasket failure (renault 1.5 dci)

Needless to say, I wasn't disappointed... it didn't work! Sorry!

I can see it could work on a radiator or heater matrix, or possibly oil to water way on the head gasket, but not the combustion chamber I'm afraid.

Fingers crossed though, you've nothing to lose bar a few quid in giving it a try, just don't hang your hopes on it....
Did you pour it in the reservoir when the coolant was hot?
 

froggy

Member
I know I'm very likely to hear people telling me to avoid using either of these products, but in the situation I'm in I really have nowhere else to go.

The engine in question is a TDI 1.4 (75) and thanks to the help of some good people on this forum the diagnosis is that I have a pinhole in the head gasket or a tiny crack in the block.

The problem is not yet severe. I can drive all day at 50mph with no problem apart from loss of coolant. The engine only overheats when I hit 60mph. There is no emulsion in the oil, nor any sign of any leaks. Can't see any steam from the exhaust either but I'm losing coolant at the rate of half a litre per 100 miles.

The thing is, as much as I love the car, cosmetically it's as rough as old boots and just not worth the heavy cost of a head repair. My plan therefore is to keep the engine going as long as possible. When it finally gives up on me I'll be looking for another A2.

In the meantime I suppose some sort of head sealant is my best option and I was wondering if anyone on here has experience of this type of product with the TDI engine.

K-Seal is certainly the easier option as it will mix freely with antifreeze/coolant and therefore does not require flushing out the cooling system before use.

Wondarweld can only be mixed with water which means the cooling system has to be flushed through twice (before and after application).

K-Seal is cheaper too so would be my preferred option unless I hear from someone with experience that Wondarweld is a markedly better product.

I know it's a shame that I find myself in this predicament but them's the breaks! Wish me luck.
My TDi 75 AMF had K-Seal poured in by the previous owner in an attempt to seal a coolant pipe leak. As the hole was massive, It failed miserably at this and made a heck of a mess to boot, but after some repair work and flushing, so far so good. I’m hoping my block is undamaged. Newer engines would most likely be wrecked by this product. As you say if you are not willing to shell out £££’s for a head gasket repair then you have nothing to lose. There may be people out there who would take it off your hands and repair it themselves, but it depends on the mileage and if other areas of the car are rough you would nearly have to give it away. I would say K-Seal is your best bet, unfortunately I can’t say if it will work or not. Good luck!
 

A2Dreamer

Member
My modus with the head gasket failure went to webuyanycar. I declared the HGF and they offered me £80 for it. I told them that I could get more as scrap and they upped it to £180 😂 which I took as it was less hassle than scrapping it!
 
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