case pressure...

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Crabtrap62
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case pressure...

Post by Crabtrap62 » Sun Sep 03, 2017 8:12 am

Alright guys , i have a PE90/520 engine, and i belive that my case vent hose is kinking while i'm running building up too much case pressure , because now i have a [new] oil leak , from what i can see is out of the cylinder/block/case flange. Could case pressure find a way around the cylinder seal causing this leak.My work schedule as kept my out of my shop, but , moving the vent IS on my to do list.

teeoter
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Re: case pressure...

Post by teeoter » Fri Oct 06, 2017 12:39 pm

Worn valve guides and or worn rings can cause excessive case pressure. Look for dirty black oil on a low time oil change that will indicate exhaust gases are getting into case.

SWAMPHUNTER45
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Re: case pressure...

Post by SWAMPHUNTER45 » Sun Oct 08, 2017 10:24 am

Let us know how that works for you and if it corrected the blow by. While I am NOT an A/C guy there had been numerous folks who have reduced some of their blow by by using a heavy blending of Lucas in their oil.

If your leak and blow by continue you may want to search some of the old threads on the use of it and see if any ratio was discussed. I remember several guys down south a few years back who had good things to say about it helping them. Obviously it is not the cure for a defect but it can help in the case of normal wear by sealing better around the rings etc. Just a thought

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John Fenner
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Re: case pressure...

Post by John Fenner » Mon Oct 09, 2017 12:14 pm

Well, most likely it doesn't have anything to do with case pressure, vs either too deep of the champher where oring seats under cylinder base, or the thru stud wasn't sealed correctly when case halves were assembled.
I never finish anyth,,,.

GMAC 76
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Re: case pressure...

Post by GMAC 76 » Mon Oct 09, 2017 3:14 pm

kinda answered your own question didnt ya?......if the vent hose is kinking then the pressure will build.....fix the kinking vent hose so the crankcase can breath!!!!!

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