1975 135 Johnson Shifting Issues

[markdclay]

Gents, I just picked up a 1975 135HP Johnson. Runs fine on the trailer, but has issues shifting into reverse and forward. I replaced the lower end oil but no change. I adjusted the linkage, which helps, but it still pops out of gear under load. It seems as if it won't quite engage fully. To get it to stay in gear, I have to over adjust the shift cable, and thus lose the opposite gear (adjusting it to stay in forward more causes the throw to be to short for reverse) Could it be a stretched control cable? Shift dog? Any ideas?

 

[Hooty]

Re: 1975 135 Johnson Shifting Issues

Start with the water pump and see what it looks like. I'm bettin' it's wore out.<br /><br />c/6<br /><br />Hooty

 

[Hooty]

Re: 1975 135 Johnson Shifting Issues

Disregard that last post. It belongs somewhere else.<br /><br />Thx. & c/6<br /><br />Hooty

 

[markdclay]

Re: 1975 135 Johnson Shifting Issues

I'll take a look. Just for my information, how does that affect the shifting ability? Does the waterpump drive the shift assister ?

 

[markdclay]

Re: 1975 135 Johnson Shifting Issues

OK, hooty. I was a little confused!

 

[OBJ]

Re: 1975 135 Johnson Shifting Issues

Hi Mark...<br /><br />From the sound of your post it may be your clutch dog and/or forward gear dogs wore out. The dogs on the clutch dog and gear should be square and sharp. Over time and shifting, the sharp corners can "roll" over and will not stay engaged. Don't mean to be scary, but yours sound "very" worn out. May be a good idea to pull the guts out of the lower unit and take a gander.

 

[markdclay]

Re: 1975 135 Johnson Shifting Issues

Thanks OBJ. Look's like the lower end HAS to come off. I'll let you all know what I find!

 

[OBJ]

Re: 1975 135 Johnson Shifting Issues

Me again...<br /><br />Just to a look at the parts break down of your engine and lower unit. The shifting is assisted by a mechanical piston cylinder in the lower unit. The sealing area is accomplished with orings. It looks as if that it would be possible for one of these orings to "leak" through and cause your problem. I would suggest a service manual for tear down and assembly and maybe a parts book. I believe your problem is in the lower unit and all the adjustment in the world won't help yer problem.

 

[markdclay]

Re: 1975 135 Johnson Shifting Issues

I saw the piston in the manual also. I'll have to tear it down and take a look. I'll hope for an o'ring, but expect a dog(s)! Thanks again for your help, and I'll let you know what I find.

 

[OBJ]

Re: 1975 135 Johnson Shifting Issues

OK Mark and Good Luck!! Hope it ain't to bad.

 

[markdclay]

Re: 1975 135 Johnson Shifting Issues

Gent's, sure enough it was the clutch dog and the forward gear interface completely rounded over. Thanks for all of your help...