Mike v.t.s
Active Member
If its the tappet thats a bit sticky diesel will cure it, when i do a oil service i normally put about a pint of diesel or (just under) into the engine oil 15 mins befor i change oil, let it run while your gettin the tools ready then drop it all while its still hot, that works better than any engine flush.
Derek Ward
Active Member
I've used engine flushes for years but I've never heard of that one before. Makes sense though as it'll thin it out but still lubricate ok. I'll give it a go next service. Cheers Mike.
lanmjdun
Active Member
What are the symptoms of a sticking valve, how does it manifest iteself?
Mike v.t.s
Active Member
I sware by the diesel method, ive serviced V12 diesel CAT engines and allsorts, i just put more diesel in depending on the size of the engine etc, ive tried all the "super gizmo" bull**** engine flushes etc etc, its normally parafin based pr something similar anyway... nothin cleans out the tappets like good old diesel, you can use RED but there is more detergent in white (shell esso Bp etc)
Thats my TOP TIP for the day, happy servicing fellow P38'ers.
It maybe an injector sticking open and over fueling. If a valve stuck open it would make love to a piston. If the valve was bent it would be a constant problem. Unless a tappet barrel is sticking which highly unusual, but that would surely bend a valve i would think.
Mike v.t.s
Active Member
I agree with the tappet barrel, very unusual... id go for the injector "hoseing" (dribbling) but normaly this happens on tickover so when you rev it would then clear, as the pressure increases and the piston is wapping up and down sooo dam fast it has no choice but to burn the fuel, i say normaly but we all no how P38's are NOT NORMAL lol
chip2366
Member
i have put new injectors in and it still the same i will just have to try and flush it with diesesl again and let it soak over night the last time i had this problem i filled the engine up to the top with diesel and left it to soak and it worked so i might have to try it with this one just dont turn it over when engin full of diesel
eightinavee
Well-Known Member
Does it run one of those plug in powerboxes ? If it does just try unplugging it - I had one just like that last week,unplugged it and it was fine.
If a tappet barrel is sticking it will be gored and would need taking out and cleaning. Very unusual if it is that. Unless there has been very old dirty oil in the engine over a long period. On engines with a few miles on them it is also very unusual for a valve to stick unless it is bent. Valve wear smaller, guides wear bigger not tighter. Think the only thing it can be, if indeed it is a sticky valve, is the tappet barrel. Unless you have a broken outer valve spring. I suppose at higher RPM with higher oil pressure the inner one may be weak enough to allow the tappet barrel to over extend slightly.
Mike v.t.s
Active Member
The average life span for hydrolic tappets is around the 100,000 mile mark give or take a little depending on differant engine companys, so it could just be stickin, they tend to wear slightly just at the point where the valve sits up to the tappet causin slight movement and as time goes on "slap", this slight wear and "slap" could be enuf not to let the valve open enuf or make the annoying "sticky tappet" noise.... so how many mile has your engine done??
In all honesty tho ive seen engines with 250,000 mile on the clock with original tappets and they sound sweet as a nut (V.W) you could be unlucky with yours...
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