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mrf240Z

Rocker Arm off, smoking engine!

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Question, my motor was smoking I looked at the plugs and #3 was covered with oil, all others looked good. I found that the rocker arm for the intake was completely off the valve spring!!! So, why would oil leak down and should I pull the head and get it checked out? What are your thoughts? Burned Valve? Rings can't be washed out because intake was closed...Help!!

post-1409-14150791860782_thumb.jpg

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That rocker arm did not just fall off. There is a reason why it came off and you need to find out what it is.

I also noticed that the lash pad is missing in your picture. You don't want that floating around loose in your engine. If you are lucky, it is in the oil pan, but no matter what, you need to find it (or all the pieces).

If it was my motor, I would be pulling it down and probably be rebuilding it (assuming it is not recently built). Of course, I have the tools necessary to do the work quickly.

If you need the car, can find the lash pad, the cam and rocker are OK, and can put all the parts where they belong and re-adjust the valves, you might try putting it back together and see what happens. The risk is that the next failure may still occur and be much more expensive....

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I pulled the head, ordered a new cam from motorsport...the springs seem to be ok, but a few of the valve seats were worn and one was completely loose-fell off when disassembled (valves). New pads, rocker arms and a new valve job...hoping to get it back together next week. I suspect there was some valve float and improper adjustment, but I am taking care of all the top end for now. The bottom end 'seems' to be in good shape...although I would like to match the E88 head to a L28 block this summer

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Watch those springs! We change them (stock Nissan parts) every 10-20 hours on our ITS car. By the time they need to be changed, vavle float has dropped from 7500 rpm to below 7000 rpm. A quick check is to put a new spring next to an old one and compare height. The correct way is to measure both free length and spring tension. My experience is that when the free length is too short, spring tension is also too low. They seem to track each other fairly well.

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