fresh rebuilt top end (now smokes)

[jamin690]

Hey all,

Well with some assitance from the forums I was able to get my 787 engine's top end rebuilt. The problem now is that it smokes. The engine runs better than the non rebuilt, i am getting almost 7400RPM out of it. I started to take it apart again to see if I could notice any oil leaks (not that I know where one could come from on the top end) and as I removed the exhaust manifold I noticed the new exhaust manifold gasket has an oil stain down the flat side of it. Because this smoke's more at idle and clears up when running at speed, I think this is a leak that is getting oil into the inside of the manifold which is then smoking, but I am here on the forum's with this because I wasn't aware of any oil that should be making it that high up in the cylider.

any thoughts is greatly appreciated.

 

[timmyboy76]

hey...pull the plugs and cover with rag, kick motor over and see if oil is present on them...hopefully its just a offset oil pump, and not seals leak'n....:cheers:

 

[derek]

i have a feeling you are losing the center seals on the crankshaft. smokes a lot first fire-up of the weekend, right? better after a few minutes? i would just live with it for now. do the crank over the winter.

 

[jamin690]

Thanks for the suggestions guys, I will do that rag trick to see how much oil is going to that engine. It actually smokes when its at low RPM, when I run it fast the smoke goes away then after a minute or 2 of low speed it comes back. I hope there are no seals gone in the bottom end, they were fine before I rebuilt it. With any luck its an adjustment on the oil injector, but I am not confident on how to make that adjustment and I am certainly hesitant because I don't want to turn it too low and hurt the enigine.
any tips with this would great.

Thanks

 

[derek]

check the lever on the oil pump. it might be hung up in the full flow position. that would give you correct oil for full throttle, and way too much for idle. BUT; the crank seals would act the same way. a way to check would be to remove the oil pump or unhook the big hose that goes to it (plugging the hose of course) and running 40:1 premix.