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New member and need HELP !!!
68 GTO... Pontiac 400ci 6.6 liter...I blew a head gasket last Fall....had it fix ($$$)
I got it going this year to blow another head gasket ??? brought it to different mechanic who ending up tearing the engine down to the cam shaft. We replaced all the Pistons and sent the heads out to be done over. Painted the block and dressed it all up. Now i'm noticing Oil spray from new Baffled Valve Cover breathers ?? It seemed to run good until I punch the Tri Power in...It coughs, hesitates and sputters and when I open the hood...Oil all over the place ?
Whats my problem ????
 

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I would say you have too much compression combined with too much fuel from your ends carbs. I would do a compression check on your cylinders. The oil coming out sounds more like blow by or lack of compression but since you said you had 2 head gaskets blown I would say you have way too much compression. When you step on your end carbs make sure you have close to 3000 rpms. Below that it will bog down if you dump those ends carbs in. Do you know what your jet sizes are on your ends?
 

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To word your problem another way, when you step on the end carbs it is putting so much fuel into the cylinders that the unburnt fuel gets mixed with the oil on the side of your cylinder walls and the high compression blows out the mix all over your engine. Smaller end jets. And still check your compression.
 

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Discussion Starter #4
"thanks"

Hi "Roger that";
My Mechanic took off a fuel regulator after rebuilding the engine....said we didn't need it....(it went from the gas line to the Carbs). I just put it back on and will run it today to see how it works ? i will also get a compression check too !!!
thanks for your help and happy GTO ing .....
 

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High compression will not cause excessive blowby out of the breathers. Leaking piston rings will. Perhaps the rings still need to be seated? (can take 1000 miles or more). Also, you ARE running a PCV system, aren't you?
 

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Also be suspicious about having removed that regulator. While not related at all to the oil problem, if you've got too much fuel pressure now (due to the missing regulator) that can cause all kinds of stumbling and drivability problems --- up to and including an engine fire.

Trust me, you don't want to go there.


If everything about the tri-power is set up right, you should be able to punch it from ANY rpm. The only problem will be needing to visit your chiropractor to have your neck popped back into place :D

Bear
 

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oil spray

I agree with most of the replies. I just did a break in on my newly rebuilt 389 with Tri Powers in my 65. Upon start up I had oil coming out of the breather in my original style unbaffled valve covers. It appeared that the fan does a great job spreading the oil mist all over the engine bay. No harm done and was a messy although relatively easy clean up. At about 100-150 miles the engine started to settle down, rings were starting to seat and the misting disappeared. If the engine was rebuilt properly, decent break in, the more miles you put on the happier the engine is; oil, plug and temperature wise. I am not sure I would get on the Tri Powers until you get a few more miles on and you get the rings seated. Solve one problem at a time. Just my 2 cents.
 

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Sorry if i misdiagnosed the problem with the oil. As far as your tri-power stumbling it could be too lean as well with air leaks. If you are too rich you should see a ton of black smoke coming out the exhaust with all carbs in. What i meant by having close to 3000 rpms with the tri power is if your in the 1:1 gear or your final gear and you pullling 1200 rpms and give it all 3 carbs, the engine just will not take all that fuel at a low rpm and will bog down.
 
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