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Engine Leak Stop Oil

dkaraledkarale Member Posts: 3
Does anybody use STP's Engine Leak Stop Oil before? Does it work? Any feedback on this product is welcome. Thanks.


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    Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    It just swells the seals...it may work temporarily on some types of seals, but soon enough the seal gets so rubbery it will leak again. Generally, a waste of time but if you need a stop-gap measure for a few days, it may sorta kinda work for a minute or two. I myself would not put such a thing in my engine for fear of it affecting seals that are okay at the moment. It does not discriminate, after all.
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    peshleman1peshleman1 Member Posts: 5
    I use the STP stop leak in my 22 year old IH scout. When I bought it 4 years ago the rear main leaked real bad. It would leak about a quart every 200 miles of driving or so. I didnt pay much for the scout and I use it as a beat around rig so I figured what the heck I`ll give it a try. Anyway the stuff works. It didnt completely stop the leak but it got it down to a drip which surprised me considering how much it was leaking. I have to put in a new bottle every oil change though. Anyway considering what I would have to go through to change the rear main seal I`ll just keep using the stuff. If you have a newer vehicle I would recomend getting the problem fixed right though. Most of the time its the high mileage vehicles that start leaking anyway so if thats what you have give the stuff a try. If your oil pan is leaking or valve covers try tightening them up before you try the stop leak. Sometimes that will fix the problem on high mileage vehicles. Just dont overtighten them. Anyway the stuff works for me and my situation so give it a try it might work for you.
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    0patience0patience Member Posts: 1,712
    When you put a stop leak into your engine, you have just committed yourself to having to keep putting it in or you will have a worse leak eventually.
    As Mr Shiftright said, it swells the seal to seal it, then it will wear a new surface on the seal and stop or slow the leak. Sounds good so far, right?
    After a bit and a bunch of oil changes, eventually the stop leak will start to come out of the seal. When it does, the seal will shrink back to its original size, now this may take a while, but it will happen. When it shrinks back to its original size, you think it will only leak as much as before, wrong.
    Remember about it wearing into the seal? Once the sela shrinks back, the gap is now wider and a bigger leak.
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    raaizinraaizin Member Posts: 31
    I agree with peshlman1. Have a 90 t-bird which has 170k miles on itwhich I use for commuting. I do put one in with every oil change. I try to but the generic type from Pep Boys, they only cost a dollar or so. I cant see spending the money to do a rear main when the car has so many miles. I just think it would be foolish to start throwing money at an old car. As soon as something big goes, it will go to the junkyard.
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    Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Well, I can't argue with that logic when we are talking about very old, high mileage cars, but I'd never put this stuff in a car worth anything...it just makes the problem worse eventually....stop leak is "stop-gap"....which means you are then supposed to do something to fix the leak.

    But hell, a car with 170K on it...I'd just add oil and keep some kitty litter under the car when it's parked.
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    wtd44wtd44 Member Posts: 1,208
    Please keep your Identity hidden! The IH police are surely looking for you by now... Ha! As you know, the IH Scout is practically of cult status; certainly true in the snowy western states. My point is, sell it before it goes down for the count. The collectors and restorers would be glad to get it.
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