1977 Johnson 20HP 20BAL77

[rmos]

I have a 20HP Johnson outboard which slips out of forward gear.
In the beginning this only happened occasionally when going over ~30km/h. To prevent it from slipping out of gear, I blocked the lever when going over 30 km/h using a small cord. but after a while it got worse and now it slips out of gear constantly. (when going more then 5 km/h).

I suspect the clutch dog and/or the forward gear is worn out, is this likely the case?

I'm having trouble finding any information about this engine, On most engine part sites this partnumber (20BAL77) does not show up...
Even worse; according most sites Johnson did not produce any 20HP engines in 1977???

Is there another engine type which uses the same lower unit? how can I find out which replacement parts I need?

any help would be welcome!

 

[kbait]

Re: 1977 Johnson 20HP 20BAL77

I can't find that model on my normal search sites, so I googled the model number and found this: http://www.maxrules.com/OMC_models_files/JOthru79/70-79.html

I couldn't find part numbers there, but perhaps if you contact them, they can help with that.
Good luck!

 

[kbait]

Re: 1977 Johnson 20HP 20BAL77

You could also call Tim's outboard 218-682-2331 with the model number. They may have good used parts for it, or at least get you the part numbers..

 

[oldcatamount]

Re: 1977 Johnson 20HP 20BAL77

You are describing a bad clutch dog which are still available and not to expensive. That 20BAL77 should be the model number, but I'm not in the shop and can't look it up for you. Check the Salvage Yards in the Top Secret File at the top of this page for a company that has the parts.

 

[Vic.S]

Re: 1977 Johnson 20HP 20BAL77

20BAL77 is listed in the model year guide on the shop.evinrude.com site

http://shop.evinrude.com/media/document/ModelNumberReference.pdf

and it is a 1977 20 hp

I suspect it is a Belgium made model. They sometimes dont appear in the US parts lists, presumably when they were models exclusive to the European or UK markets.

The fact that the OP uses km/h for speed suggests he is not in the USA.
I would not expect anyone in the Uk to use it either for that matter.

He has not stated his location in his profile !!!!!

Jumping out of gear is almost certainly due to a worn dog clutch and possibly gear too. Slipping, but staying in gear could be due to a failed prop hub.

 

[rmos]

Re: 1977 Johnson 20HP 20BAL77

I'm from the Netherlands, so that I have a Belgium model sounds plausible...

But the question remains which clutch dog I am looking for, could I replace it with a clutch dog from a 25 HP US model from 1977? Or should I use a Belgium replacement part?

 

[Vic.S]

Re: 1977 Johnson 20HP 20BAL77

It should say on the Serial/model number plate where it was made.

A Johnson/Evinrude dealer in the Netherlands should be able to recognise the model number and supply the correct part.

If you really get stuck try Oakley Marine in the UK www.outboards-direct.co.uk


It'll be a surprise if it is not the same part as earlier US 20hp models and 25 hp models through to 1978 #316501 but at the price you cannot afford to gamble.

 

[boobie]

Re: 1977 Johnson 20HP 20BAL77

I would recommend replacing both the dog and the fwd gear. Once they start jumping or slipping they're both done.

 

[boobie]

Re: 1977 Johnson 20HP 20BAL77

I would recommend replacing both the dog and the fwd gear. Once they start jumping or slipping they're both done.

Sorry about double post, pushed wrong button.

 

[rmos]

Re: 1977 Johnson 20HP 20BAL77

I've disassembled the gearbox and the clutch dog and forward gear don't look to bad I think. (See attachment)
My plan now is to get the edges sharpened by using a milling machine, what do you think, could this work?

 

[levi_tsk]

Re: 1977 Johnson 20HP 20BAL77

thats odd it doesnt look bad? could your linkage have been out of adjustment???
maybe some of the other guys will chime in here and correct me but seems like that isnt the problem unless the angle of the shot is hiding it?
could you get us a pic off to one side a bit of both parts?

 

[rmos]

Re: 1977 Johnson 20HP 20BAL77

Thanks for the reply!
You mean the shift rod? could be; but I tight the shift lever with a cord to keep it in forward position, and even then it slipped out of gear... So I suspect there is a problem with the clutch dog.

Attached are some additional pictures, from different angles.

Would milling out be an option? does any of you have experience with this?

Thanks in advance!

 

[rmos]

Re: 1977 Johnson 20HP 20BAL77

and some aditional ficture of the forward gear:

 

[samo_ott]

Re: 1977 Johnson 20HP 20BAL77

Huh. They dont look that bad. I'd try reversing the clutch dog and reassemble and adjust the shift linkage and see what happens.

Some folks hace tried milling but from what I hear if you mill though the hardened part and then it get softer and wears fast. But this is only hearsay, I've never tried it.

 

[78 mckee]

Re: 1977 Johnson 20HP 20BAL77

There is also a bushing or bearing in the forward part of the gear case. If that bushing/bearing is worn, or if the shaft is worn and cocks in that bearing, it will cause the clutch dog to slip out of the forward gear.

Gary

 

[rmos]

Re: 1977 Johnson 20HP 20BAL77

78 mckee, I'm not following you; do you mean the busing pointed by the arrow in the attached picture?

 

[78 mckee]

Re: 1977 Johnson 20HP 20BAL77

Actually, the arrow is pointing at the bearing surface of the forward gear. The bearing is the next component at the edge of the thumbnail photo. It's called the forward bearing. It is a bronze bushing that fits into the most forward part of the gearcase and the forward gear rides in it. If that bushing is worn, as many become, it will allow the output shaft to **** under load and the clutch dog slips back into the neutural position. I actually have a older model gearcase like yours, sitting beside my workbench, with this very problem.