Hi all,
I've just done a full rebuild on my MC21 engine - dry clutch model. New crank, pistons, seals, gaskets. etc etc etc. I've used Three Bond 1207B throughout.
Before I put the motor back in the frame, I've done a leak down test.
Left cylinder slowly leaking from 5psi to about 2.5 after 5 minutes. Right cylinder a little faster.
I cannot find the link anywhere. All the gaskets, crank seals and crankcase seams are OK. No bubbles visible at all and I've triple checked with soapy water. I've checked the carb boot/manifold area very closely and that is also good. The oil pump is installed. The only thing i can think of is that there might be something I've not blanked off? An oil channel or similar?
Any help or suggestions would be really appreciated. After dropping nearly $2k into the motor I'm pretty keen to see that I don't ruin it on the first ride.....
Cheers, Simon.