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Johnson 8hp wont engage reverse

Z

zyweik

New member
"Hi guys.

I have an oldish

"Hi guys.

I have an oldish 8hp two stroke.. I'm unsure of the year becuase I don't know where to look to find an engine #, serial # or anything like that..

Anyway, my problem is that it won't engage reverse. Forward and neutral are fine but when you move the lever to reverse it stays in neutral. Any ideas? Would it be a broken linkage? Or is it more serious > a broken cog/spline ??

I've never worked on an outboard before (only cars) so "long winded" explanations of things would be great.

Cheers."
 
if you can let me know where t

if you can let me know where to look to find the model number i'll be able to tell you.. bought it second hand > i suspect its from the 80's but that doesn't help much..

i can get photos if there are distinguishing features which help pin the model down..

cheers.
 
there should be a plug about t

there should be a plug about the size of a quarter on top of the motor it will have the model#s.

also look around on the brackets for the model and serial #s. they should be there......unless someone removed or painted over them.
 
"Hi Jeff,

I think the earli

"Hi Jeff,

I think the earliest you'll find an 8HP is 1984 apart from a few from before the dawn of time. For a few years before 1984 there were some 7.5 hp models

The drive shaft has on its bottom end a bevelled pinion which meshes with two gears on the prop shaft. They of course will be rotating in opposite directions. A dog clutch locks one or other of those gears onto the prop shaft to give forward or reverse drive.

This diagram shows an '84 system. #17 is the pinion, #8 is the reverse gear,#15 the forward gear. The dog clutch is #12 which is operated by plunger #33. Not shown in this diagram is the gear lever and vertical shift rod. essentially though the movement of the lever is transferred to the vertical shift rod by a pair of bevel gears. The cam # 29 is on the bottom end of the shift rod and transfers the rotational movement of that to the plunger.

later in the 1980s the design was changed to that shown in THIS DIAGRAM You can see that the old type of dog clutch has been replaced by parts #12 and #33

At some point in the 1990s a design appeared in four strokes in which the shift rod had a push-pull action and the dog clutch was operated by a yoke #13 and #36 in This diagram
The design for 2 strokes reverted to the earlier design.

Sorry rather hastily compiled and I hope not too many inaccuracies but with luck gives you some idea how they work."
 
"Continued:
You'll find

"Continued:
You'll find these diagrams and others with the parts list HERE

When you have located the model number you will be able to ID it from This list

You can just see the location of the model and serial number plate on the transom bracket In this picture"
 
thats awesom stuff VicS ... th

thats awesom stuff VicS ... thankyou very very much.. I'll have a ponder over it and see if I come up with any questions/answers..

cheers.
 
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