Black76

I rebuilt the engine in my 76 the owner before me installed a big block 454.
I pulled the engine this summer and rebuilt it, had the michine shop do the work on the bottom end new rings pistons and had it bored 20 over.
and the shop also rebuilt the stock heads.so after putting the top of the engine back together and installing the engine. It started up fine and even runs strong but the problem is on the driver side exhust i have some blue smoke should i be worried or do i have to wait for the rings to seat.i have not driven the car just running it in the garage right now so it has no miles on the rebuild just maybe 30 or 40 mins of run time.

joewill

you have to at least drive it to try to get the rings to seat. no sense even trying to complain to the shop until you try to break it in..

hopefully they told you the procedure...

Black76

Im not looking to complain to the shop just wanting to know if this is normal i know blue smoke is oil just not sure if its the rings or the heads or how long does it take to seat rings ?

oldsarge

Drive it for awhile to get it broken in, then see if the issue clears up.

ajrothm

It shouldnt be smoking. Rings will be seated in the first 10 mins its running....

I'd wait till after you get it together and a put a few miles on it to see what it does but....That way you burn out anything that may have been in the header tubes or exhaust pipes. Make sure to put the engine under some significant load, don't baby it too much...Also allow it to decel a few times with engine braking.

*Also if the car is an automatic, disconnect the vacuum hose for the vacuum modulator on the tranny and see if its full of fluid. If so, replace the modulator as the engine vacuum is pulling tranny fluid into that port the vacuum T is on...

* It could be sucking oil in through an intake gasket OR you could be pulling oil in through one of the rocker studs if you didnt put sealer on them.

1) Drive it first and see what it does. If it keeps smoking go to step 2.

2) Try to determine which cylinder is the culprit, pull plugs and inspect them. If one cylinder is a smoker, I would pull the intake and check the ports to see if there is oil in them....if so, change the gaskets...if not, go to step 3.

3) Check the oil seals on the cylinder that is smoking, maybe the seal got buggered up during installation. It happens. If the seals are good or replaced, moved to step 4.

4) Id do a compression test and leak down test. This will not necessarily indicate which one has bad oil rings but this can tell you a lot. If one cylinder has a noticeably higher psi or tighter leak down, that "could" indicate there is extra oil in the cylinder, then I would be suspect of the rings on that cylinder. Maybe an oil scraper ring got folded over or butted up or something.

Do that stuff and report back.

hugie82

I had a cracked Teflon valve seal leaking on my BB427. They banged it on so hard it cracked. Try checking the plugs to narrow down the oil burning.

markbett

I had the same thing happen after my rebuild, turned out to be that I needed baffled valve covers. The vacuum was so strong after the rebuild that it was sucking oil back into the intake. I was blowing smoke all the time, all the plugs were covered, it was a mess. After the new valve cover, clean as a whistle!.

Black76

were you blowing smoke on both sides or just the driver side. What valve covers were you using right now i have the Micky T valve covers and im only smoking on the driver side

markbett

Dude, I am so sorry, I keep forgetting that I have a fuel injection system on my car. No carb! I'm not sure where the PVC re- enters a carb system. I'm sure if you look you'll be able to tell if the return hose from the PVC is positioned towards the front or the back of the carb. I'll bet dollars to doughnuts that where ever it is, it feeds right to the drivers side intake.

I got my baffled valve covers from JEGS.

Sorry i didn't get back to you sooner, I'm heading to the Ocean City Boardwalk corvette show in Ocean City, NJ.

markbett

More info, check the plugs and see which ones have oil on them, as stated above.

Do a compression test as stated above. Any garage can do this cheap if your not familiar with the test.

If the test comes back clean, you got an intake problem from the PVC, if you find a leak (low compression), go back to the rebuilder and have him check everything

Black76

Yes the pvc value is on the valve cover on the driver side and also thats the side thats smoking so you think that is whats causeing it to smoke

markbett

I would eliminate the simple and cheapest stuff first. One way to check is to block the PCV valve with a plug and run the car up at full temp for a while, it might run a little rough but if the smoke clears up, bingo.

If it doesn't pull the plugs find which ones are covered in oil, do a compression and leak down test on those cylinders. That will tell you a whole lot. I did these tests right off the bat and they came back clean as a whistle. So I knew the oil was coming in from the top.