Reverse problems on 83 70hp merc

[cjnspecial]

Hey Yall,
I put a seal kit in the lower unit(prop seals, shift shaft seal, bearing carrier o-ring, complete water pump, etc) and reverse would not engage. I dropped the lower unit again and moved the shift shaft lever to the reverse position and turned the prop to be sure the clutch was engaging reverse gear. Well....the gears will engage if I turn the prop(CW) slowly but if I put any torque on it or try to spin it quickly, it just slips. Foward and neutral work fine. Before I re-install the l/u, is this normal?
Any help or advise you can offer is greatly apreaciated.

 

[tashasdaddy]

Re: Reverse problems on 83 70hp merc

what did the edges of the clutch dog look like? square and sharp or rounded and worn off?

 

[cjnspecial]

Re: Reverse problems on 83 70hp merc

IIRC, the clutch dogs had a tiny bit of wear but were not rounded off. Reverse engaged fine before I took the l/u off so it shouldn't bee too worn out.
Looking at the diagram, it can only be 3 things:
1. Clutch or reverse gear dogs worn
2. The clutch is not being pushed back far enough to fully engage
- Which would indicate the Cam Follower or cam gear was worn.
3. The reverse gear is not far enough back in the housing.

Since everything worked before, I'll assume # 3 is the culprit. Maybe the bearing carrier nut needs to be tightened or it's not seated in the housing correctly.

 

[cjnspecial]

Re: Reverse problems on 83 70hp merc

The bearing carrier nut was not tightened up enough. Once tightened up, it shifted like a charm.