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5.0 exhaust smoking oil after recent H/C/I swap

727 views 1 reply 2 participants last post by  squekster 
#1 ·
I recently completed an H/C/I swap and was able to drive my car about 100 miles with no problems. I was coming up from my house to show it to my uncle, who didn't think I could do it. I had about 100 miles on the motor and 2 miles to go to get to his house when blue smoke came spitting out the back. Half the neighborhood came over and thanked me for clearing out all the bugs for them(thats what I get for knowing everyone) and they all gave me a hard time, but my uncle helped me find some garage space to try and figure out what was going on.

Originally, I suspected that the piston to valve clearance may have been the issue since the new heads I had installed had 2.02 intake valves, although I notched the pistons to get the optimal 0.080" of clearance on the intake side. The exhaust side was nowhere close to hitting, so I left them alone. I also used the converted solid roller lifter for the measurements.

I pulled my valve covers off and found the intake rocker on cylinder #3 had slid off of the pushrod and valve. I'm guessing the compression without the intake opening caused the oil to get pumped up through the piston rings and valve seal.

I need to find the answer to 2 problems, 1. What caused the rocker to fall off the spring and rod? 2. Did I cause any damage to the rings/valves/guides/seals with the piston trying to pump air through a closed valve?

Anyone have any ideas or advice on what I should be looking for, or what my next step should be?
 

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#2 ·
Without the intake valve opening that cylinder couldn't possibly be firing. You should have noticed
and engine miss. I don't think any damage was done to piston rings or valve seals. The only way a rocker
could slide out of place would be way too much valve lash or a collapsed lifter. The fact that the intake did not
open that would create a vacuum strong enough to pull oil vapor from the crankcase not the valve seal since the
valve was closed. Pull the plugs and you will probably find the one or more that is burning the oil.
 
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