Lync and Sync 1988 - 40HP

[Greg2011]

Lync and Sync 1988 - 40HP
Page 1- 40 Service Manual 1987 Models 40 thur 55

Step 6 in link and sync?
“Warning: stop the engine to prevent contact with rotating parts.
To adjust the pickup timing, loosen the jam nut. Rotate the top of the thumb wheel toward the crankcase to increase pickup timing degrees and away from the crankcase to decrease the pickup timing.”
The book has a picture of the jam nut – see my Picture 1
Book picture # is 12773
Pickup timing 3 degrees + or – 1 degree BTDC.

This step adjusts the carb linkage? If you adjust the jam nut, you push on the black roller that moves the throttle plate.
Either you’re at idle: black roller off of the cam or your increasing rpm because you are pushing on the throttle plates with the black roller.
Picture 1

The timing is done below the flywheel with what the book calls idle speed adjustment screw step 10.
You have to move the timing plate under the flywheel to change timing; the linkage goes to the idle speed adjustment arm.
Picture 2 and 3

Is the book written wrong on step 6?
The rest of the steps are OK.

 

[racerone]

I think the book is CORRECT !!--------------Review your understanding of what they mean by ------PICKUP TIMING.----------Or post what you think it means.

 

[Greg2011]

Link & Sync my belief or miss-understanding?
Note: I am a weekend novice trying to keep an old motor running, not a 2 stroke tech person , or OMC engineer, or a service manual technical writer.

Link & sync is the process of synchronizing the carb linkages with each other and synchronizing the ignition timing plate linkage to advance when the throttle plates just start to open on all carbs.
I should change the title to: Sync & Link

You’re Question?
Pickup timing:
My neighbor has a 2000 Chevy pickup truck; he is always late for school. His mother said the pickup has bad timing, not her son.
We call it pickup timing! Just a little humor! But it is a true story.

The service manual does not define the word pickup, but it does give a specification on the adjustment, this is a quote “(Pickup Timing) (35A – 50) (3 degrees plus or minus 1 degree BTDC)”
I would call that initial timing, idle timing, or low RPM timing, but the book does have Maximum timing as an adjustment. So minimum timing would seem appropriate?

Put wait there is still more!
The sequence of events in this adjustment is called: “(Cam follower Pickup Timing)” Step 1: Hook up a timing light to plug wire #1. Step 2: Advance the throttle plate till the amplifier or throttle plates just start to move. Step 3: start the engine and observe the spark advance. Proper spark advance is in the chart: “(Pickup Timing) (35A – 50) (3 degrees plus or minus 1 degree BTDC)”
Step 4: “Warning: stop the engine to prevent contact with rotating parts.
To adjust the pickup timing, loosen the jam nut. Rotate the top of the thumb wheel toward the crankcase to increase pickup timing degrees and away from the crankcase to decrease the pickup timing.”
The book has a picture of the jam nut!
Step 5: Repeat 1- 4

Timing advance is mechanical, with a rod linking the throttle lever with the timer base. Idle speed is completely controlled via spark timing; throttle valves are always fully closed at idle.

So in conclusion the step 4 is very confusing to the week end warrior.
I would set the idle timing with the idle adjustment screw, and then adjust the arm - jam nut - so the cam - lower mark - would contact the black roller to sync the timing between ignition advance linkage and linkage for the throttle plates - just start to open.
Is pickup timing defined as: When the engine picks up RPM?

They are just words, adjusting an outboard engine should be made simple. The problem is most people cannot get their engines to idle right, which is a safety issue. Most people have the idle to high, come into a dock or marina to fast, they pull it out of forward, get neutral, going for reverse which is really BRAKES, the engine dies, they have to get out of reverse back to neutral, try to get the engine restarted, get it back into reverse, but by then they hit two kids on a jet ski, and hit a boat tied to the dock.
Brakes do not work because of Sync and Link - bad idle

 

[racerone]

You run the engine and advance throttle and thus the timing till it is running at 3 degrees BTDC----------------then turn the key OFF and do not move throttle control.--------------------Now adjust the cam untill it just touches the roller !!!!!---------You are done.----------------Idle speed is set with the stop screw in your middle picture in conjunction with the throttle cable.----------There is nothing wrong with the instruction in the manual.