Ask a Mechanic Online and Get Answers to Your Car Questions
Did you check to see if the exhaust valve hit the piston?
Do you think the rocker failed because of a lack of lubrication? Any signs of that? Was the lifter or valve train tapping before? Does the rocker look blue or is there any small metal shavings laying around?
Did you check that the new push rod does squirt out oil when running?
Actually I am getting ahead of myself. After I typed this I continued to read and see you had already answered some of these questions.
Ok, no or little signs of oil? Is that both sides or just the one? I assume you did run the engine without the valve cover and look. Have to checked the oil pressure?
What weight of oil are you using? Did you add any STP to the oil originally when doing the longblock for breakin? If so, is it still in there? Have you changed the oil filter yet?
OK, I originally suspected that it may be a valve hit. I put the borescope down the cylinder after we poured Marvel Oil in the cylinder to see if it would leak through. (this is what the warranty tech told us to do) the marvel oil ate some of the carbon off the piston and I discovered a notch that looks manufactured and not a valve hit. It is wedge shaped and has very clean lines. None of the other cylinders has the same mark that we can tell. This worries me but the tech said they may put in different pistons. He couldn't come with a picture of one. I have never seen such a thing but I have seen valve strikes and this doesn't look like that. As I said we did a leak down compression test and there is no sign of exhaust valve not sealing. The rocker failed because the pushrod came out from underneath it. The rocker shaft was badly gouged on the bottom so I don't know what happened first.
Now we are getting great compression and a good leak down.
I only have the one rocker cover off. I can not see if the push rods are squirting any oil but the engine sounds normal. We did not use any STP for the break in. Have not checked oil pressure but no light is on and engine sounds normal . I just don't trust the no oil thing.
Different pistons? Do you believe that?
Well, so the exhaust valve isn't bent, that's good.
I don't think the oil light will come on untill it's under 1 psi, you should check the oil pressure.
I don't believe that but I also don't know what to think when we have good compression and the leak down doesn't show a bad valve or rings etc. I guess I will check the oil pressure and go from there. I was hoping someone would say "hey old man, we build tighter more efficient engines these days and they don't spray oil all over the place with the rocker cover off. Thanks, XXXXX XXXXX help.
Yeah, check that oil pressure.