Perkins 4-236 gearbox

[goodnumbers64]

The transmission with my 4-236 has failed. The manual says it is a Borg Warner 71 CBR. I believe it has about 3500 hours on. Boat is a 1980. Has anyone replaced one of these and can tell me how much it might cost and where I might find a rebuilt transmission? Or am I better off having this one pulled and rebuilt?

[model 10]

It might help to know where you are. For example, there are several transmission shops in Florida that could do an ovhl. The folks at Transmission Marine Inc. in Ft. Lauderdale have helped me out from far away.

[shakey doug]

Failed is pretty open ended, give some glues as to symptoms there is a lot knowledge on this forum and it is free to all.

[goodnumbers64]

I am in souThern New England. Cape cod. Had a long motor trip from the Chesapeake. During the trip the trans developed a whine. No whine in neutral, pitch varied with rpm. Then a loud noise like nuts and bolts in a clothes drier. Shut down and added about 16 ounces of oil. It ran at low rpm to get us to our home port but before reaching the mooring loud noise again and now forward propulsion. Seems to have reverse, with noise. Oil was full. Also, oil was black.

[shakey doug]

Black oil indicates severe overheating, caused either by distorted/ collapsed clutch plates, unserviceable bearings or gear alignment. G.box will have to be pulled for access to internals. B&W boxes are very simple to pull down 10 mins will see the job done. BEFORE starting removal check filter for metal particles, screen rhs in sump side as viewed from aft, remove pipe first. If you find this chocked with heaps of other material you have found the trigger to the problem

Good Luck.

[franrick]

Mate, it might not be your gearbox and just your drive place. If your drive plate fails you will get nothing when you put it into gear, forward or reverse.

All I can say is that if it IS the drive plate, your costs will be much lower than any other option. Good luck.