Link-n-sync for dummies

[Reggie08]

I need some help

Trying to make sure my first attempt at a link-n-sync on an 85 'Rude 90hp was done correctly. I finished a complete rebuild on this motor (burned up piston) and wound up replacing the block with one in much better condition (old one has scored cylinder walls and was already bored .030 over). In the process, I tried not to disturb anything I didn't need to i.e. timing screw, etc and took plenty of pictures prior to disassembly. However, since I moved everything over, I want to make sure I have this all set right.

I figured out the throttle plates. That was easy. Somewhat figured out my timing pointer (actually set it while I had the cylinder head removed but didn't use a Piston Stop tool)

My confusion really comes in when trying to set the timing advance lever. How far back is a good starting point? I'm assuming the throttle/shift cables should be removed. Where exactly should the cam follower be setting against the cam prior to moving the cam lever?

Basically, is there a "Link-n-Sync for Dummies" out there? I have an OMC Service Manual but with out any good starting reference points, it's hard to know if I'm doing this right or not.

 

[SKEETR]

Re: Link-n-sync for dummies

If I were you I would try the Joe Reeves method and time the motor out of water without starting it up. Just do a search on this site it is posted many times. At least it will get you within a degree or two and get you on the water for a final check according to manual.

 

[tashasdaddy]

Re: Link-n-sync for dummies

it is in the engine faq forum.

 

[Reggie08]

Re: Link-n-sync for dummies

I printed his post out and figured that out easily enough Sunday From what I could tell, the motor is set at 24 degrees which is where it needs to be. I've been told the Maximum Spark Advance is 28.

But is that all there is to a link-n-sync?

What about the cam follower pick-up timing? It's to be set between 3 and 5 degreeds BTDC. The first time I checked it, it was reading TDC. So I adjusted it to read 3 degrees. But any slight movement of the throttle/spark advance lever and it changes. Where should I set those levers to check/adjust the pick-up timing?

 

[iwombat]

Re: Link-n-sync for dummies

That's just the setting the max timing part of the L&S. There should be a detailed description in your manual. It's different on every motor. If there's something specific you're not understanding, post it up and we'll help you with it.

"What about the cam follower pick-up timing? It's to be set between 3 and 5 degreeds BTDC. The first time I checked it, it was reading TDC. So I adjusted it to read 3 degrees. But any slight movement of the throttle/spark advance lever and it changes. Where should I set those levers to check/adjust the pick-up timing?"

Line up the mark on the cam, then adjust your timer base so the advance reads 3-degrees BTDC.

 

[Reggie08]

Re: Link-n-sync for dummies

This may sound stupid, but where should the follower be lined up on the cam with regard to the first mark? Should the follower be centered? Just above? Just below? And how do I know I have the throttle/spark advance levers is the right position before adjusting the cam follower?

I'm assuming this, so correct me if I'm wrong. I make sure the carb/throttle plates are shut completely on the upper and lower carb (that part is easy). Once that is set, I move the throttle/spark advance lever and/or cam follower so they're lined up properly (this is the part that is most confusing to me since I'm not sure what a good starting/reference point is to make sure my adjustments are correct)

I can check the WOT throttle timing per J. Reeves' post and even the cam follower pick-up timing. Those things were easy for me to learn as well as making sure the carb throttle plates closed simultaneously. It's adjusting this one step that seems to be giving me fits. I'm to the point I want to take it to the shop but A) I hate to spend the money and B) I'd much prefer to learn how to do this for future reference.

So if I ask a...ok...lots of stupid questions, I apologize.

 

[72SideWinderSS]

Re: Link-n-sync for dummies

With the Shift and Throttle cables disconnected, and the Throttle Shaft Amplifier connected, advance the throttle arm until the Shaft Amplifier just moves.

Start the engine as is, Check the timing and see if it is between 3 and 5 deg.

If not then advance or retard the Throttle arm until the timing is correct

Check the cam and roller to see if they line up.

If not Shutdown the motor, remove the bolt that holds the cam to the block and adjust the cam until they line up.

Hope this helps.

 

[Reggie08]

Re: Link-n-sync for dummies

Alright. I think I got this figured out this morning. Just one question. I attached the throttle amplifier. But I just need to know how much the amplifier should move before I stop advancing the cam? What I did was look for the slightest movement from the amplifier as I advanced the cam and that was it. Basically, as soon as I seen the amplifier start to rotate, I stopped. It probably didn't move 1/16". Is that the proper method?

 

[Silvertip]

Re: Link-n-sync for dummies

Link&Sync aside, did you determine what killed the first motor? You said you didn't touch anything with the linkages when you reinstalled the new motor. Chances are unless you do a proper carb cleaning and rebuild and do a proper link&sync form A-Z you will destroy the new engine. You really need a factory service manual specific to your engine. It explains everything you are asking.

 

[Randyg123]

Re: Link-n-sync for dummies

Alright. I think I got this figured out this morning. Just one question. I attached the throttle amplifier. But I just need to know how much the amplifier should move before I stop advancing the cam? What I did was look for the slightest movement from the amplifier as I advanced the cam and that was it. Basically, as soon as I seen the amplifier start to rotate, I stopped. It probably didn't move 1/16". Is that the proper method?

By 'throttle amplifier' do you mean a wire attached to an aligator clip attached to the throttle shaft? My Clymer's manual mentions to do this but I didn't see this tip in the OEM. If this is what you are talking about then "YES" the first instant you see the amplifier wire move is where you stop and set the cam follower so it lines up with the mark on the cam. This way, the instant your throttle plates are opening, the cam follower is against the cam and is lined up with the top mark on the cam.

 

[Reggie08]

Re: Link-n-sync for dummies

Link&Sync aside, did you determine what killed the first motor? You said you didn't touch anything with the linkages when you reinstalled the new motor. Chances are unless you do a proper carb cleaning and rebuild and do a proper link&sync form A-Z you will destroy the new engine. You really need a factory service manual specific to your engine. It explains everything you are asking.

I'm fairly certain it was a high-speed jet that clogged. When I tore it down the #2 piston was burned up. I've been keeping a close eye on the plugs for the first signs (hopefully) of any problems. Up to this point they've looked good 'cept for some fouling with the richer mix of oil in the gas during break-in. Additionally, I bought an OMC Manual off ebay before I tore into this motor. Once I sat down and really start to think things over, I was able to figure it out pretty easily.

By 'throttle amplifier' do you mean a wire attached to an aligator clip attached to the throttle shaft? My Clymer's manual mentions to do this but I didn't see this tip in the OEM. If this is what you are talking about then "YES" the first instant you see the amplifier wire move is where you stop and set the cam follower so it lines up with the mark on the cam. This way, the instant your throttle plates are opening, the cam follower is against the cam and is lined up with the top mark on the cam.

My manual showed a small rod attached to an alligator clip. I wound up making my own using a nametag clip and popcicle stick

 

[72SideWinderSS]

Re: Link-n-sync for dummies

Alright. I think I got this figured out this morning. Just one question. I attached the throttle amplifier. But I just need to know how much the amplifier should move before I stop advancing the cam? What I did was look for the slightest movement from the amplifier as I advanced the cam and that was it. Basically, as soon as I seen the amplifier start to rotate, I stopped. It probably didn't move 1/16". Is that the proper method?

That is correct.

 

[Reggie08]

Re: Link-n-sync for dummies

Thanks Jimmy!

 

[wahoo 16]

Re: Link-n-sync for dummies

after talking to shop guys, linc and sync is pretty much as described in manuel . not to complicated, if doing as the book says and still having problems. probably some other issue. on your first run of the season when it seemed to work, you were probably powering thru your intermediate fuel circuit, didnt notice there was a problem. when you used it again putting more use to mid range you discovered there is a problem. iyou can adjust intermediates in carb, richen them, if not adjustable talk to someone who can suggest a solution to a lean intermediate fuel circuit.

 

[wahoo 16]

Re: Link-n-sync for dummies

w/ boat on trailer or secured to dock by ski hooks on back, and carb boxes removed, throttle up to the bog or stall point, gently move your hand back and forth as if to cover carb mouth (one at a time) , this should choke and stall motor. if it smooths the motor out or makes it run better ,that is your problem carb, the intermediates should be richened somehow.my omc manuel shows an intermediate orifice in your float bowl. dont know which way #s go but try gettig size that will enrichen.

 

[Reggie08]

Re: Link-n-sync for dummies

I will definitely try that tip wahoo! Thanks for the heads-up. I'm hoping to get the boat back on the water Thursday. I wanted to do it today but the winds were brutal today and in an 18' flat-bottom, it can make for an interesting ride.

 

[SKEETR]

Re: Link-n-sync for dummies

Just an obvious note, but part of the symtoms of my boat when I bought it. Check the condition of the roller sleeves on the cam as well as the throttle. Mine were nice black plastic sleeves all shiny and coated with grease. They should have a meaty bit of rubber around the plastic sleeve. A lot of slack can occur making accurate adjustments impossible.

 

[Reggie08]

Re: Link-n-sync for dummies

Quick update:

Just got back from a quick 10-15 minute trip on the lake to see how she'd run after re-doing my lync-n-sync and she ran like a bat out of hell! Ran and idled real nice!