bad blow by

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Feb 4, 2004 | 08:53 PM

dnmyoda

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From: Vermont

bad blow by

a freind of mine has an 86 150 with a 300 it has two ports plus the oil filler on the valve cover and we are getting a lot of very high pressure blow by from the front port which we piped in to a bottle for now and the dipstick tube is pumping it right out also two of the cylinders have real low compression about 30 this moter has less than 70000 origonal miles any ideas on what is going on with this thing i have never had one with less than 350000 have problems and over that it was always the intake gasket

Feb 5, 2004 | 07:22 AM

low-side

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I don't know how much you've worked on the truck, but usually a pcv valve and a breather filter will get the violent blow-by under control. With all this blow-by and low comnpression on 2 cylinders, it sounds like your friend has been running rich for a while now. A product like restore might help, but I'm not sure.

Feb 5, 2004 | 02:07 PM

wtroger

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Sounds like the either bad rings or cracked or burnt piston(s).

Feb 5, 2004 | 03:23 PM

Bob Ayers

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From: Durham, NC

Are the 2 cylinders adjacent to each other??? If so, then the low compression could be a cracked head, or blown head gasket..
If they are not adjacent, then I would say the rings are stuck or broke for those 2 cylinders. Has this engine set for a long time, where it might have gotten some water into it???

Feb 6, 2004 | 08:12 PM

dnmyoda

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From: Vermont

the truck had an engine fire two years ago and had to be rewired the fire was due to oil from the blowby the cylenders are next to each other #4 and #5 we just rebuild the ignition system to get it back running and i figured head or gasket but i wanted to check with you guys first

Feb 7, 2004 | 08:04 AM

rmt

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From: Wesley Chapel, FLA

The engine had a fire two years ago. Since the fire was caused from oil due to blowby, then the engine has had extreme blowby for well over two years. And now you want to get it going AGAIN.

Buddy, the engine is PLUMB WORN OUT.

Do the rest of us a favor. Park it till it's fixed right. The way it is now is hopeless. It's beyond shot. If all this happened in less than 70000 miles then it's either lack of maintainence or some parts have failed. Or it wasn't built right in the first place. Things like this don't just "happen".

Feb 8, 2004 | 03:48 PM

dnmyoda

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From: Vermont

id say bad ownership and quakerstate oil tore the valve cover off and it is so gunked up im supized it even runs a freind of mine had a 300 with over 300,000 on vavoline and the only problem they had was an intake gasket