On my 1969 S2 I have some coolant seeping from the front right hand side of my cylinder head. There doesn’t seem to be any evidence of coolant leaking from anywhere else.
I’ve read the archives and there seems to be positive results from people using Barrs Stop leak and Prestone Super Stop leak. I’ve been on these product websites and there are numerous different products from both these companies.
Can anyone recommend a product that has worked for them and if so what was it?
Thanks Andy
I would re torque the cylinder head. A long shot but the price is right
I’ve used the Prestone Super Stop Leak i my Jag for almost 20 years, and it’s never once failed to stop the leak in minutes.
Regards,
Ray L.
I hate Barr’s Leak: I have had far more, less destructive results with K&W Heavy Duty Block Sealer, from NAPA.
Did any of those things plug up the heater core?
No: if used per the instructions, I never had a core or radiator plugged up with K&W.
No, not one bit.
Regards,
Ray L.
I’ve used this stuff
It stopped some seepage I had before I had the engine rebuilt.
I used barrs but ended up pulling the head followed by the engine for a rebuild. The Barrs leak did make a mess around the freeze plugs and elswhere.The car sat for 30+ years.
I used this after Paul told me about it on my XJ6 engine and it lasted for about 10 years. The leakage was coming from the passenger side of the block as well. I didn’t have any issues with the heater core either.
Good luck,
LLynn
Ray,
you mean you have had repeated leaks over 20 years and used repeated application s of this stuff?
Yup. I toss in a can pretty much every time I do a flush and fill.
Regards,
Ray L.
Silly question, but do you simply add to the tank? Will it migrate to the full system
I remove the radiator cap, drain out a bit of coolant via ther drain cock and then pour the stop leak in the radiator and top it up. You’ll introduce a bit of air into the system so save what you drained out of the radiator to top off the overflow tank as necessary.
I will second the K&W. After some research I used it in my 1970 for a seeping head gasket about 4 years ago. It’s different in that you have to run it through, then drain it and let it dry overnight. That must be why it doesn’t clog things up. It worked and my car does not overheat. Recommended it to a friend after that and he used it in a car and a backhoe with success.
Unfortunately I don’t have a cap on my radiator as Its a S1. So, I’d need to remove the top hose to do something similar
My flattie-engined Jeep developed a HUGE cooling jacket crack, that drained the coolant into the sump in minutes: as a last ditch attempt before swapping in a new engine, I used the K&W stuff.
It fixed that crack, and lasted 4 years.
I became a believer!
You could just drain a gallon of coolant from the radiator, mix in the goop, and then pour it back into the the header tank.
I did this last week and it stopped my slow leak. But that was on a recently rebuilt engine with new head studs and only 1,400 miles on it. They all seemed slightly under when I torqued them in sequence. On an older engine you might snap a head bolt. Evaluate the risk before you try it or go with the liquid fixes.
That’s a great idea. Sometimes I can’t see the forest for the trees. Thanks!