Mbl transmission slipping

Mbl in 1953 23 holiday. Slipping at approx 2100 rpm. Boat is newer to me. Replaced engine oil in case was not non detergent. Currently have the boat in the water, hoping to find out if I need to pull the engine over the winter or it’s a fix I can do well it’s in. Thanks for any help. Bill

Assuming that you’re not using synthetic oil in the engine, cause that would definitely make the transmission slip. There is an adjustment on the transmission drum that is there to adjust for slippage. I don’t have the manual with the pics of the adjustment bolt but someone here will have that.

Thank You. Found a few videos from woodie restorations also. Adjusted the drum one notch as the video showed! worked great and does not slip!! Thanks Again.

:+1: