1968 Johnson HydroElectic transmission

[cstoliker]

I have a 1968 55Hp Johnson OB.<br /> Motor runs good but I am having trouble with the HydroElectric transmission. If I fill it with gear lube it will work fine for about an hour but then will start slipping out of gear above about 1/4 throttle. When I pull the boat out of the water I can see the gear lube (now turned white and milky) leaking out of just about everywhere. I can't see any cracks or problems with the case. I have no idea what the insides of an OB boat transmission looks like. Is it possible for the gear lube to be leaking internally or would it have to be one of the gaskets like between the Transmission and the lower unit? I am of course using the correct gearlub for Johnson hydroelectric transmissions. Here are some pictures taken just after taking the boat out of the water.<br /><br /> http://www.cstoliker.8m.com/Boat/BoatTrans.html

 

[OBJ]

Re: 1968 Johnson HydroElectic transmission

Best thing to do is drain the lower unit and see if the gear lube inside is milky colored. If so, you have a seal(s) leaking. The replacement of them is not a difficult job but would require the removal of the lower unit if the seals below the water pump are at fault.<br /><br />You may get a better idea if you had a manual to go by. OEM manuals are prefered over the generics.<br /><br />To test the lower unit for leaks is kinda easy. Drain the lower unit of gear lube. Rig a bycycle pump to drain or vent plug. Put a few pounds of air pressure in it and dump the thing into a garbage can full of water. Any bubbles means a leak. You might also pull the prop and take a visual of the prop shaft seals. These are prone to catch fishing line which can really tear up the rubber in the seal.<br /><br />Take a look and do the pressure test. About 5 to 10psi is all you need to find a leaky seal.<br /><br />Keep us posted....thanks.

 

[kd6nem]

Re: 1968 Johnson HydroElectic transmission

I'd not put it off either. Check what is in it, if it is milky get the water out and flush with clean lube to prevent rust. Type C isn't cheap but I'd flush to get water out then discard the "new" fluid, do the pressure test/repair asap. Some seals will be replaced more easily with factory tools from what I hear. I've heard some people suggest automatic transmission fluid as a flush. I never tried that, myself. Seems like it would be fine. Remember to install a new impeller if you have to take the LU off.<br /><br />Sweet motor if everything is working right. If a seal is all you need (sure sounds like) then it is a very worthwhile motor. Just make sure the electrical harness is in excellent condition. Long story, but I know from experience.