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I didn't start her today, but I did charge the battery and then do some prolonged starter spins to make sure oil is pumped everywhere in the engine. In the process I found some oil on the front of the engine - a large drop on the starter, right in the center. I looked for where it could be coming from, and didn't see anything obvious. I ran my fingers on the fin below the exhaust ports, and I picked up some oil from doing that. A visual inspection showed nothing - but that oil came from somewhere. I bet I'm going to have an oil leak. Wonderful.

I may try to start her tomorrow, but it's more likely it will happen Friday.

Happy Thanksgiving, everyone!

I've encountered 47mm tappet cover O-rings with two different cross-section dimensions that are included in rebuild kits, intended for CA/CB/CL 72/77's. The thinner ones measure about 2.9mm, the thicker are about 3.2mm. The thinner ones may not properly seal against the head, as that surface may have some fairly coarse machining. Tracing a leak of fresh, nearly clear oil from below the covers, running down to the fins, then dripping downward (usually from the bottom of the header pipe will take a bit of patience. That would be the first area I would pay close attention to. There are also tappet covers that bottom out on their threads before the o-ring is compressed. See if you can slide a .003" feeler gauge between the o-ring and the sealing surface to verify. Regards, Chase

cknight wrote:I've encountered 47mm tappet cover O-rings with two different cross-section dimensions that are included in rebuild kits, intended for CA/CB/CL 72/77's. The thinner ones measure about 2.9mm, the thicker are about 3.2mm. The thinner ones may not properly seal against the head, as that surface may have some fairly coarse machining. Tracing a leak of fresh, nearly clear oil from below the covers, running down to the fins, then dripping downward (usually from the bottom of the header pipe will take a bit of patience. That would be the first area I would pay close attention to. There are also tappet covers that bottom out on their threads before the o-ring is compressed. See if you can slide a .003" feeler gauge between the o-ring and the sealing surface to verify. Regards, Chase

Hi, Chase! Happy Thanksgiving!

I think I've found the source of the leak, even though it's not 100% verified. It seems to be coming from the center of the head gasket, the cam chain gallery. Do you suppose that retorquing the head bolts would stop it? I will check the tappet covers, but the area below them does seem dry.

I'm going to start her up, anyway. The good part of this is confirmation that oil is being pumped around inside the engine!

It is just POURING oil around the galleries on the left rear and right rear of the head gasket. The left side is FAR worse than the right. I mean it POURS oil! I know those O rings are in there. I'm thinking the engine has to come off the frame and the head has to come off. Bad gasket, maybe? I don't know. This is REALLY frustrating and beyond disappointing.

I did put some gas in the carbs and hit the starter. "pop-pop-pop...." It fires, at least.

Sara,

What torque values did you use and did you re-torque the cap nuts a second time after letting it sit a while?

HT

Hoosier Tom wrote:Sara,

What torque values did you use and did you re-torque the cap nuts a second time after letting it sit a while?

HT

Tom, 21 ft pounds, and yes, they've been retorqued.

I'm going to pull the engine. I spoke with LM, and I need to check to be SURE I have the gaskets on the air/oil separator on the top of the head are facing the right way, and if they are, the head comes off to see what the deal is. Something is way wrong. From what I understand these engines DON'T leak oil back where this one is.

Keep the faith! Frustrating, to say the least, but you'll get it sorted out

HT