Link and Sync Help - Running Rich?

[gnarbrah]

Hi all - I'm still trying to get my 1988 Johnson 20hp running in top shape. I finally got the carb all put back together and it starts up nicely on 1 or 2 pulls and will run pretty well. Problem is it idles pretty rough and just doesn't seem to have the quick response time at throttle up. Once I get planed out it seems like it gets smoothed out and cruises well. When I'm at 3/4 or less throttle it really seems to me to be running rich. It has a little puddle of fuel sitting in the carb in front of the butterfly - is that normal? I'm pretty much sold on the fact it needs a link and synch and that's where I'm lost. I have the OEM service manual for 9.9 through 30 hp models. In the link and synch section step 1 is cam follower pickup point. It says to advance the throttle by moving the "throttle control lever" and when the amplifier conncted to the butterfly shaft begins to move the cam follower should be making contact between the 2 marks on the cam.
Ok - I know this may be a dumb question but which part is actually the throttle control lever? I can move all kinds of different things to advance the throttle and I want to make sure I'm pushing the right one!

Next on this subject my cam follower will make contact at the correct point but only if I manually move the cam. If I twist the tiller throttle up and then back down it is about an inch to the right of the cam follower. Is this normal? The adjustment for this section of the link and synch only moves the cam follwer in and out from making contact with the cam - it doesn't do anything for aligning the the follower in between the marks on the cam.

It says very clearly to not skip steps and to do them in order so I haven't moved past this step 1. I did however read ahead and it only seems to get worse, down the line it has me running the engine with the proper test wheel (what is that????) and not to have the prop on and not to use a flushing adapter??? Any help is appreciated and if it sounds like I'm going to do more harm than good I won't be offended if you tell me to just bite the bullet and pay someone. If that's the case - any idea what that might run?

Thanks - I'm ready to get this thing running like it's supposed to

 

[gnarbrah]

Re: Link and Sync Help - Running Rich?

Am I sunk?

 

[rusirius]

Re: Link and Sync Help - Running Rich?

Ok - I know this may be a dumb question but which part is actually the throttle control lever?

The throttle control lever is whatever you use for throttle control. If it's a tiller model, then it's the throttle on the tiller... Whatever you use while you're out on the water to "go faster"...

Next on this subject my cam follower will make contact at the correct point but only if I manually move the cam. If I twist the tiller throttle up and then back down it is about an inch to the right of the cam follower. Is this normal? The adjustment for this section of the link and synch only moves the cam follwer in and out from making contact with the cam - it doesn't do anything for aligning the the follower in between the marks on the cam.

One problem I had a while back while doing a sync was that my butterfly wasn't adjusted right... Turn the throttle to WOT... Look in the throat of the carb and make sure the butterfly is sitting horizontal or 99% to horizontal... You don't want it going PAST horizontal and you don't want it not getting anywhere close... Depends on your engine, but this should be adjusted by a "stop" somewhere... Basically when you first start turning the throttle the timing plate will start to move... It should move a bit before the "stop" will make contact with the control lever for the butterfly...

If you're butterfly is adjusted right, then move on to the sync...

You're right that the adjustment will be moving the follower in and out, but that's not really what you're trying to do...

Turn the throttle all the way down to idle and SLOWLY advance it... As SOON as the butterfly shaft moves STOP... Now look at the cam follower... Is it right between the marks? If it's BEFORE or AFTER the marks you'll need to move the adjustment a little and try again... Repeat the process until it's EXACTLY between the marks when the shaft begins to move.

I did however read ahead and it only seems to get worse, down the line it has me running the engine with the proper test wheel (what is that????) and not to have the prop on and not to use a flushing adapter???

A test wheel is basically a "ducted fan" of sorts... It's designed for use in a test tank... It puts the proper load on the motor but doesn't push a TON of water around like a real prop will... I would guess that this section you're getting to is the timing... As long as you haven't messed with the timing advance stop, it's most likely fine and you're probably better off not messing with it... You need a timing light anyway...

As for a flushing adaptor... That's what is normally refered to as "muffs"... It's sort of like a set of "ear muffs" except they go over your water intake ports instead of ears... You hook a hose up to it and it supplies water... Basically it allows starting the engine without having it submersed in water... They are designed to quickly flush out salt water... The reason the manual says not to use them is because you should never run the engine at high rpm (or much above idle for that matter) on muffs... The prop has no load on it without water...

 

[gnarbrah]

Re: Link and Sync Help - Running Rich?

Sirius I can't thank you enough! That is exactly the kind of info I was looking for. I've been staring at the book and the motor for weeks now knowing there must be something I was missing. I went to check the butterfly and it was opening 80% (100% being horizontal) at best. The adjustment I made was with the screw that adjusts the cam follower in and out if you move it to extremes which I did not. Now the butterfly is at a solid 97-98%. I'm a little nervous to go much more as I don't want to trash anything. From that I got back to looking at where the cam follower met the marks on the cam. The marks were still about an inch over to the right (looking out the back of the boat) when the butterfly shaft started moving. I then traced all the linkage back to see why and I think I may have found it! The little ball socket thing (which I had replaced earlier because it was cracked where it screws on and held together with a zip tie) that comes from the throttle linkage in the tiller arm to connect to the linkage in the "block" area wasn't screwed on far enough. I screwed it all the way down and I think the cam follower hits between the marks pretty good!

Question here is what exactly would the marks being over an inch from where they should be cause? Running rich and just "not quite right"? I'm really hoping so.

I'm not going to go any further into tweaking anything because I don't have that magic test wheel or timing light or any of that stuff. Just going to go try and start it now and see what happens!

Thanks again Sirius!