The Notorious Stop-Leak Instructions

I have found the section in the factory manual for the Jaguar XJ-S, purchased around 7 years ago, that includes the instructions which have doomed the bottom halves of many an OEM radiator and presumably contributed to the reputation for running hot and overheating these cars have been saddled with. It doesn’t out and out say to use stop-leak in your jag every time you change the coolant, but 14 oz of leak inhibitor being noted as a standard component of a fluid service might just lead some people to believe you’re supposed to use stop leak whenever you change the coolant.

Yes, this is the most shitty corrective action to clumsy UK design I have ever seen. Tear this bit away and use after upcoming lunch… The crap they’re recommending to pour in. It’s like making sure you will be coming back to the workshop…


XJ even worse - they got other things wrong too but this is particularly bad.

Oh wow, that is even worse. I guess that’s one way to do planned obsolescence

I wonder if this could help lead to dropped valve seats? Not only do the radiator passages get narrowed, but passages in the head too?

That stuff has been around for years, and I admit to using it to temporarily fix a leak in a radiator. It did disastrous work on the heater core, clogging it up completely.
Now, on to modern times: Cadillac had a common problem with their mostly aluminum engines in the 80’s, and short of pulling the heads for blown gaskets, they offered a ‘fix’ in a little plastic tube, that you could purchase at the parts counter at GM dealers. I was told it was ground-up wings and parts from a beetle. This proves that high technology has been around for some time.

I wondered why I don’t seem to see very many VW’s around anymore.

Someone told me a great temp fix for a leaking radiator, water pump, etc…pepper! It will stop the leak so you can get home, and will easily clean out.

There’s a story about using an egg, too.

You know , last year I heard about that story about pepper. So I dumped about two or three capfuls into my 2002 Jeep Liberty to stop a leak. The Liberty didn’t really have a radiator cap , at least one I could find. So I dumped it into the overflow top up tank . After about an hour of going into the store and coming out the tank got plugged , exploded in the parking lot , never sure it ever got to the radiator but a $1000 later had to replace the radiator and tank anyway.
Last note, it did plug some holes for sure.

Way back when my first t had a very leaking radiator. Solution, a big can of water. or stop at a gas station. water was free.

Much pleased when one of Dad’s friends sold him a pristine T radiator for two bucks. The beginning. it was for a 27, and my car was a 23. The 27 a tad taller. but, with a shiny nickle shell!!! At first, just omit the hood. Then, swap bodies for a 27 Roadster !!!

Off the frame restore… Red chassis, grey engine. grey body, red wheels…

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