20 hp Chrysler drive problem

[nukko]

My early 70's 20 hp runs fine up to about 1/2 throttle but when I increase throttle it acts as if something is stripped in drivetrain -- feels and sounds like it is momentarily slipping out of gear and back in and out and in. Hope someone has an idea. Thanks

 

[eurolarva]

Re: 20 hp Chrysler drive problem

Hello Nukko. Have you checked the lower unit oil for metal debris. The oil should be dark like regular oil. Let a few drops come out of the lower fill hole and rub it between your thumb and fore finger. If you see metal deposits in it you may have damaged gears. Hopefully it is just a shift linkage adjustment. Does this noise happen in reverse as well?