View Full Version : STOP LEAK

05-21-2004, 05:52 PM
I'm willing to bet this topic has already been thrashed over on a prior thread but if it has, I can't locate it. Wynn's engine "Stop Leak" sounds like it was invented for LBCs. It "helps stop internal and external oil leaks" it claims. My Healey continues to mark its territory and I've got a pretty good idea why. Can this stuff actually help? Has anyone ever evaluated this substance in any kind of rigorous fashion?
Thanks for the insight and if this has already been gone over before, my apologies.

05-21-2004, 06:37 PM
I don't think Wynns can make a Big Healey stop leaking oil. The engine wasn't designed to be oil tight. There is no oil seal at the back of the engine, like there is at the front, so some leakage is bound to happen.

If Wynns can plug the seepage there, I would be concerned that the crank would gall there, because it wasn't getting oil.

Dave Russell
05-21-2004, 06:55 PM
I would put it in the same category as the rest of the snake oils. The MSDS sheet for this product shows only petroleum oil. I suspect it is mostly 50 wt motor oil, which might reduce leaks slightly but no more than just dumping in a can of any 50 wt oil.

Most of the reported successes with this sort of additive are from the "psychological placebo effect" - If I paid good money for it, & hope it works, I will likely think that it helped.

05-21-2004, 07:10 PM
The only thing with a similar name that might actually work is "Bars Leak", for radiator leaks.
I will admit, I've used Bars Leak and it does seem to reduce radiator leakage (the little pellets in it plug everything, probably including critical coolant passages). I'd only use it in a "junker", not a car I cared about.

05-21-2004, 07:14 PM
Oh yeh, I forgot to mention, it "also reduces oil burning". Sure........

05-21-2004, 07:43 PM
My XK engine didn't leak a drop immediately after the rebuild. Then I filled it with oil.............. /ubbthreads/images/graemlins/smirk.gif

Bruce Bowker
05-21-2004, 10:03 PM
LBC is Leaky Bloody Car! Who cares anyhow. If not real bad, just top her up.

05-22-2004, 01:54 AM
I don't think I'd try anything that attempts to stop oil leaks. It would almost have to do bad things to the oil to achieve this end. I have, however, used Bar's Stop leaks in radiators on emergency basis and never had any really bad effects. But even then, I'd only use that stuff on older cars that I didn't really car much about.


Dave Russell
05-22-2004, 04:15 AM
After studying Bar's Leak for radiators & experiene with others using it, I think it is one of a very few that I might be tempted to try. But not in my good engines, & they are all good right now. It has been the favorite of used car dealers for many years & even some new car dealers have been known to use it.

06-03-2004, 12:05 PM
For what it's worth, on a GM vehicle, they get two of the GM stop leak tablets in the cooling system before the vehicle leaves the assembly line!
Dave is right, the oil leak stuff is designed to take your money. It may contain something along the lines of glycol that will make an oil seal swell, much like using DOT 3 brake fluid in an LBC will.
The old line about "Chances are if it sounds too good to be true, it is" fully applies.