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Discussion Starter #1
So here's the problem...I have a 79 Bronco (to go with my 68 fastback of course) and i have recently purchased a new motor (rebuild) from Jasper...after driving it for a couple of weeks, It began leaking out the intake manifold rear seal...so I decided I must have f'd up the seal during install,...and just decided to redo it...at the same time, i changed the oil at the 500 mile mark...so..I do this, and within ten minutes of drive time,...it blows the seal right out,..and oil follows...smokin/burning of the headers...etc. so...as the story goes...6 more tries later, and each time the same result, I call Jasper...who of course asks me to check pcv...which is also brand new...with edlebrock manifold and carb, and everything else!..then they say I should reseal it,..and omit the rubber seals front and back, and use silicone on the valley pan instead...I do this...it works...its tight....except now, I am blowing oil right out the tops of the valve covers...!! at the breather, and by the pcv...I'm at a loss..except to think they did a lousy rebuild job....Am i mising anything? any suggestions?...I'm doing a comperession test with a friend tonight,...but I'm lost,..and clearly concerned i'm gonna be swappin this thing out again!! and of course jasper does warranty,..but not if they find something wrong when they get it back...help please!!!!!

thanks,

Dan
 

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The engine shouldnt be producing that much blowby...

Here's the million dollar question....did you REALLY drive it gently so it can break-in correctly or did you go off hell bent and are hating life because you blew your investment?
 

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there is one problem you have here--too much crankcase pressure! now you just gotta find what the cause.is your manifold(the edlbrock)new also?perhaps you don`t need the valley pan with that design.check your pcv for vacume at it`s source and it`s operation/vacume at idle and at part throttle.check your breather system out and remember there is not suppose to be combustion gases exiting from there--I bet the valley pan is your root cause, either installation or wrong application-there is either too much crankcase pressure or the pressure that is building up is not able to be released properly--a cylinder leak down test is a good way to check for internal engine problems of this nature-(gotta be catastrophic-rings,hole in piston- to be that bad) but check out that manifold and valley pan first after six times your probably pretty good at r+r/ing it







"nobody ever got anywhere by stepping on the brakes"
 

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To be as bad as it is, it must be in the engine and not something you've done. Maybe they forgot the rings. /forums/images/icons/tongue.gif

A leak down is a better test, although as bad as this sounds the compression check may find it also.

What does a Jasper Motor cost?

Good Luck,
 

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yeah valley pan!instead of intake manifold gaskets,it`s one big pan that covers the bottom of intake manifold and it is postioned in the lifter galley with intake gaskets incorporated --made of tin
 
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To much exhause backpressure can blow the seals completely out of the engine. check the muffler and exhaust system for clogs or restrictions.
 
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