1971 Johnson 60hp gearbox Problem

[NZ-Kevin]

Hi, I'm desperate for some help with my engine. It's a 1971 60hp Johnson, 60ES71C. Forward gear doesn't work. Here's a list of what happened and what I've done (sorry it's long, but I wanted to try and get all the facts I could in to help diagnose the problem).

We went out fishing theother week, no problem getting there. Spent a couple of hours fishing, came to go home and the engine started no problem, but when I pushed the control to go forwards it didn't go. The engine revved and there was lots of bubbling water (from the exhaust I presume) but no movement. Had to get a tow back

When I got home I checked out the electrical connections, and tested the switch functions and all seemed OK. Checked at the cables on the engine with power connected and got the right voltages at the right time.

Connected muffs and ran the engine, engaged forward gear and the propellor turned, into neutral and it stopped, into reverse and it turned the other way.

When the engine is turned off if I try to turn the propellor it will turn anti-clockwise (looking from behing boat) and if I try to turn it clockwise it turns the engine over (so seems to be in gear).

Drained and replaced gearbox oil. Old oil was a bit mucky, but no trace of water.

Took boat to the ramp today, started engine and tried forward gear -nothing. Tried reverse, and that worked fine. To rule out electrical problems I disconnected both wires to the solenoids, still no forward gear.

When I got home I flushed thr engine, and checked gears out. It went into both gears and the propellor went round in both gears. But I realise there is a world of difference between a prop spinning slowly in air and being driven round in water.

I've got no idea where to go next, so suggestions would be gratefully received. Also if anyone knows any repair shops in New Zealand who still know how to work on these motors it might be a help, but I suspect I'll end up having to do this myself. At least my Seloc manual arrived the other day, so if I have to strip the bottom end down I should be able to.

Thanks

Kevin

 

[NZ-Kevin]

Re: 1971 Johnson 60hp gearbox Problem

Some further info. I have just tried the obvious test, holding on to the propellor I got someone to turn the engine over by hand by the flywheel. It was possible to hold the propellor still. Could feel some resistance about twice per revolution (which is why the prop spun when I tested it under no load) but it wasn't driving as it should. Have started to remove the bottom end, as there is obviously a problem in there. Any suggestions still welcome, I'm guessing a worn dog clutch or gear.

 

[a70eliminator]

Re: 1971 Johnson 60hp gearbox Problem

Could be just a spun hub on your prop, no need to disassemble gearcase, have you looked at the shear pin?

 

[tashasdaddy]

Re: 1971 Johnson 60hp gearbox Problem

sounds like a spun prop, that it to a prop shop

 

[tx1961whaler]

Re: 1971 Johnson 60hp gearbox Problem

I've never had a prop spun so bad that it would not even idle forward under load. They still have a lot of friction even when spun.
This is a hydro electric gearcase, so it does not use the regular 80-90 weight gear oil. It uses "type C" lubricant, which is thinner.

 

[NZ-Kevin]

Re: 1971 Johnson 60hp gearbox Problem

Definately not a spun prop. I now have the gearbox stripped and the dog clutch (which Johnson call the "shifter") is worn out, but also the faces it bears against on the forward and reverse gears are worn out. New gears are far to expensive to consider, and I can't find any secondhand ones. So I'm in the process of setting up to re-machine the faces on the gears. There seems to be plenty of material in the raised area so I think it can easily stand to be machined back about 1/4" or so which should remove the damaged area and give me a nice square edge for the new dog clutch to work against. I'll have to put a new one of those on as it is too thin to machine the face back. Looks like a longer job than planned.