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Discussion Starter #1
Hello friends. Glad to find this forum. I am new to FE engines and have recently rebuilt a 1968 Ford Fairlane 500 Fastback that has a FE390 engine. The previous owner had raced this car so he installed a high performance race cam, solid lifters and heavy duty valve springs. There is also a high volume oil pump that results in me having about 60-65 psi oil pressure gauge readings when the car is going down the road at 3500 rpms. I have had the engine bored .060 over and installed an Edelbrock Performer intake and Carburetor set up. The car runs great and is quite fast considering the modest 650 cfm carb. I have only put about 500-700 miles on the engine so far. The problem I am having is that When I start the car up and have it on high idle therer is some smoke coming out of the exhaust on the drivers side only. It seems as though I can drive it some, stop and look at the exhaust and there is no smoke coming out. It's kind of an off and on thing. Also My drivers side valve cover has a coating of oil on top of it after I take the car for a drive. The oil is being forced out of the breather on the valve cover. I did a compression test and a leak down test a hundred miles or so ago and everything looks good with the exception of #6 cylinder does have slightly less compression, (140 compared to 155 on average from the other cylinders), and about 30 compared to 20-25 on the leak down. I'm thinking that the engine just needs to be driven more but I'm getting quite a bit of oil build up in my drivers side valve cover area. I think it's referred to as blow by. I am getting ready to sell this car and feel uneasy selling it to someone with this issue although it may work it's way out after putting more miles on it. The engine is a beast otherwise and fun to drive with the C6 transmission and B&M ratchet shifter. My pcv valve is connected to the passenger side valve cove and the hose connects to the front base of the carb where the vacuum is at its greatest. I am no mechanic by any means but love to work on older cars and would very much appreciate any info that might help me with this matter. Many thanks in advance.
 

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Sounds like you may have valve guide wear with the exception to the compression. Try putting a little bit of oil in the cylinder and see if compression improves, if there's no change it's probably the head\valves. While the heads were off, did you take a good look at the valve seats?
 

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The valve seats and seals were replaced when the heads were redone at the time the block was overhauled. I'm thinking that I need to install an oil catch can set up on this engine. Not sure if this is related to the smoking or not.
 

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Try the oil trick to see if compression comes up.
 

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Common cause of blowback / back pressure can be caused by restriction on engine breathing .Faulty PCV valve or restriction on hoses . sometimes collapsing under load .Faulty valve stem oil seals usually show up when engine hot , left to idle for a few mins. and then revved up is when you get a puff of blue smoke at rear . When really bad , you can see it when stop / starting in traffic .Also oil tends to carbon up on valves .
 
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