MF 65 No oil to rocker shaft
asumazim
Join Date: Aug 2011 Posts: 6 Minnesota |
2011-08-12 179802
Just did a complete rebuild on Continental G176. Got it running, runs nice. Ran it up to operating temp and removed valve cover to set valves hot. Found out rocker shaft is getting no oil. Removed rocker shaft trying to figure out how the oil is supposed to get there. Only possibility I can see is through a small hole in rear rocker pedestal base. Tried cranking engine with rocker shaft and plugs removed. No oil flowing up through hole. I have excellent oil pressure when running, 65 lbs, maybe too high? What went wrong?
Reply to | Quote Reply | Add Photo
MF 65 No oil to rocker shaft
kthompson
Join Date: Oct 2005 Posts: 5275 South Carolina Pics |
2011-08-15 179835
Not saying this is good suggestion, asking for those who know more than me to chime in: It would seem the oil patch is clogged by either trash from before the rebuild or from the rebuild. Would he stand to harm anything by applying a penetrating oil from the top side and let if soak and then applying air blast to the oil patch or could that cause another problem? ....
Reply to | Quote Reply | Add Photo
MF 65 No oil to rocker shaft
asumazim
Join Date: Aug 2011 Posts: 6 Minnesota |
2011-08-16 179865
Found a post on another site pertaining to this topic. This motor apparently does not a have a large oil delivery to the rockers. It is supplied through a small hole in rear cam bearing and journal. So once per cam revolution, the holes line up and a small amount of oil passes through, eventually filling the galley to the rocker shaft. Sounds like a poor system, but the components under the valve cover, ( tops of push rods, tops of lifters, and caps on top of valve stems ), are cupped, so once they receive oil, they retain it. Also, there is a small plug in the block behind the starter that is common to the oil galley above rear cam journal. I started motor with this plug removed, and there was a small oil flow there. This told me that oil was getting through the cam and would eventually get to the rocker. I was able to determine that the passage from the pipe plug to the rear rocker pedestal was open with compressed air. So, I finished assembling the motor, warmed it up again, set the valves, and changed the break-in oil. All is well. Ran it two hours yesterday with the brushcutter on, ran like a champ. ....
Reply to | Quote Reply | Add Photo
MF 65 No oil to rocker shaft
kthompson
Join Date: Oct 2005 Posts: 5275 South Carolina Pics |
2011-08-17 179874
Thanks for the feedback. Glad it was well. Does seem like a weak system. Just wondering what is the top RPM on this engine? ....
Reply to | Quote Reply | Add Photo
Go Top
Share This