Cannot link n sync Johnson 15hp for the life of me

[vickin]

I have a 1989 johnson 15hp tiller that I cannot sync for the life of me. No matter what I do (i.e. adjust the trunnion ball, cam follower allen bolt, idle stop on the tiller, and timing cam allen bolt) I cannot get it to start in the start position. I can get it to start and stay running (working the choke) in the start position, but by using zip ties to hold the throttle plate open about a 1/4.

The hash mark on the timing cam is always to the right of the cam follower if you are looking at the carburetor from the front. I cannot get it to line up properly. Basically the throttle plate is not open enough to start it in the start position.

I am almost to the point where I think someone installed the wrong timing cam or the throttle plate assembly was installed incorrectly.

I would love some insight, please.

​Thanks

 

[vickin]

I was always wondering if it maybe missing the sleeve on the roller? dont have a good carb to compare it to.

 

[boobie]

Try leroysramblings.com. You may get some info there.

 

[AlTn]

part # BRP 0396236 Cam Follower Roller Assembly...if you can find a pic maybe you can tell

 

[Vic.S]

deleted

 

[oldboat1]

It sounds like you are over thinking it a little -- but that you have running issues that are going to remain after that sync. The sync is not the idle adjustment -- just means your carb begins to open at the point you throttle up. Sounds offhand like you have to adjust the follower back (out, toward the front of the carb). Rotate the mag plate clockwise to the point where the follower is located roughly at the mark, and then adjust the follower down to just touch the plate at the mark. If it's a little ahead or behind the mark, adjust the plate to the point where the line touches the follower, and adjust the tension on the follower to just touch the line at that point.

 

[Vic.S]

I was always wondering if it maybe missing the sleeve on the roller? dont have a good carb to compare it to.

look at parts diagram.

Its a roller and no separate sleeve is shown although LeeRoy refers to a plastic sleeve on models after 1987. The roller is a different part number after '87 but the cam and the follower are the same

look at the roller carefully .if it looks broken up replace it. ...... Photo of the roller and follower ???????

 

[oldboat1]

might add too that the location of the twist grip really isn't critical to the carb/throttle sync. It's probably better to move the mag plate/throttle by hand. Idea is to bring the roller into contact, not the other way around. I like the older ones better, I think, because you could just fully loosen the roller, move the mag plate, then set the roller in place by hand and lock it down.

 

[vickin]

look at parts diagram.

Its a roller and no separate sleeve is shown although LeeRoy refers to a plastic sleeve on models after 1987. The roller is a different part number after '87 but the cam and the follower are the same

look at the roller carefully .if it looks broken up replace it. ...... Photo of the roller and follower ???????

Definitely missing the outer sleeve. I looked at a brand new one and mine does not look the same. I need to get a new follower.

 

[vickin]

It sounds like you are over thinking it a little -- but that you have running issues that are going to remain after that sync. The sync is not the idle adjustment -- just means your carb begins to open at the point you throttle up. Sounds offhand like you have to adjust the follower back (out, toward the front of the carb). Rotate the mag plate clockwise to the point where the follower is located roughly at the mark, and then adjust the follower down to just touch the plate at the mark. If it's a little ahead or behind the mark, adjust the plate to the point where the line touches the follower, and adjust the tension on the follower to just touch the line at that point.

When you say rotate the mag plate, do you mean with the throttle or take of the flywheel and rotate it into a different position?

 

[oldboat1]

not the flywheel, the throttle plate under the flywheel -- the plate that moves when you open the throttle with the twist grip.

 

[Vic.S]

When you say rotate the mag plate, do you mean with the throttle or take of the flywheel and rotate it into a different position?

It does not matter. but id not take the flywheel off unless I needed to for some other reason

Using the throttle control is the easiest way surely, but set the mag plate to line the mork on the cam lines up with the roller.

This is a different engine but you can see the marks on the cam are lining up with the roller. In this position the roller should only just be touching the cam. If the throttle control is turned down the roller will no longer be touching the cam. If it is increased the throttle plate in the carb will start to open. If necessary the follower is then adjusted so that the above is so.

But be warned the follower easily breaks when aged!

With luck once you fit the new roller on to the follower it will all be Ok and no adjustment will be needed.

 

[oldboat1]

good tip re that plastic cam. recently broke one. Understood you to say the setting of the twist grip was an issue, but can use it at least to see how the plate moves. But the twist grip setting shouldn't be an issue for the link/sync.

 

[vickin]

Okay. I understand that now. I ordered a new roller/follower today. I will report back hopefully this week when I get the new part installed. Thanks for help guys.

 

[raczekp1]

https://www.youtube.com/watch?v=33_tWgTwE30

 

[raczekp1]

https://www.youtube.com/watch?v=33_tWgTwE30

 

[raczekp1]

if compresion is low or pistons bearibs have some play you will never run your motor at idle speed

 

[raczekp1]

if compresion is low or pistons bearings have some play you will never run your motor at idle speed

 

[vickin]

Well installed the new roller cam. Motor started right up and idled perfectly. It is properly synced as well. Basically the roller was missing the sleeve. Thanks all for the help.