1997 J50ESL Timing linkage initial - Too long spark control rod?

[webbd]

After having issues on the water last weekend, followed by replacing the power pack, coil (again), spark plugs, throttle roller, timing roller, and primer fuel lines...

I'm having issues with timing. I went through the manual, and reset the short spark control rod to 2.5" length according to the manual (2 1/2" for models equipped with a 12 amp charging system or 2" for models equipped with a 4 amp charghing system). It was set to 2.25" (the shortest it will go). To accomplish this, I also needed to adjust all the linkages, reset the carburetor WOT setting, etc.

• Both carburetors are currently bench balanced
• The WOT limiter is set at wide-open throttle
• I reset the timing retard stop to prevent crushing the timing roller again.

You may be able to see from the picture that the spark control rod wants to be much shorter than 2.5". In this image, it's at its shortest adjustable length of 2.25" between post centers.

If I connect the spark control rod, it backfires and dies. Do I need to go to a different spark control rod? I'm looking at part numbers 334153 and 435530 and these are what I think I have.

Do I need to reset everything? If yes, how do I set the initial linkage without crushing the timing roller? Are the arrows for the timing roller just there for aesthetics, or do I read correctly that it should be between them when the engine is at idle?

Photo of linkage as-of now with throttle closed:

-- DW

 

[jakedaawg]

It appears you are missing the outer cover on the throttle cam follower roller. May just be the pick. Should be black inner layer and translucent outer layer just like the one in the timing cam.

 

[jakedaawg]

Disconnect the remote control cables before attempting the link and synch.

 

[Faztbullet]

Checked the flywheel key?

 

[jakedaawg]

I also think you may have the wrong ends on the rod that you have disconnected. They appear long to me. It probably just the camera angle though so disregard most likely.

 

[webbd]

After thinking about it all night, I did the following:

• Bought a timing light
• Adjusted the spark control rod back to 2.5"
• Adjusted the linkage to allow the engine to run with the spark control rod adjusted at 2.5"

This adjustment consisted of:

• loosening the adjustment plate on the controls so I could easily turn the adjustment wheels
• loosening the screw that adjusts throttle roller position relative to the throtle lever
• Adjusting the throttle linkage to the point where the spark control rod would snap down on the spark control lever
• Adjusting to where the engine would idle cleanly (by ear, it worked out to setting it at TDC).

I took a look at the Seloc manual and in the ignition specification sections, I could see that the idle timing should be 0d - 2d ATDC and WOT timing should be 18d-20d BTDC. The index point would have set the idle timing to 8d ATDC and that was causing engine backfire out the exhaust and failure to run. It ran well at idle on muffs at TDC.

At 3000RPM, it was running somewhere around 13d BTDC during an earlier test when I was trying to set to the numbers for a 3-cyl 50HP and had idle at 4d ATDC, but I didn't test 3000RPM after resetting. I might be able to pull the spark plugs to test WOT timing while running the starter.

After adjustment:

• Tighten the bolt for the cam spring linkage adjustment plate
• Tighten the screw for idle speed indexing
• Lock down the idle timing stop against the stop plate at idle
• With the engine off, adjust WOT and lock it down
• Put the air intake silencer cover back on.

At 3000RPM, it was running somewhere around 13d BTDC during an earlier test when I was trying to set to the numbers for a 3-cyl 50HP and had idle at 4d ATDC, but I didn't test 3000RPM after resetting. I might be able to pull the spark plugs to test WOT timing while running the starter.

Here's a photo of the adjusted linkage with idle timing set.


-- DW

 

[webbd]

It appears you are missing the outer cover on the throttle cam follower roller. May just be the pick. Should be black inner layer and translucent outer layer just like the one in the timing cam.

It's the pic. I replaced both rollers and the throttle cam roller has the outer clear cover.

-- DW

 

[webbd]

Checked the flywheel key?

There is a scratch in the paint that extends from the driveshaft onto the flywheel. It hadn't moved, but I bought a woodruff key just in-case.

-- DW

 

[webbd]

Disconnect the remote control cables before attempting the link and synch.

I didn't think to disconnect the remote control cables. I did loosen the screw that holds the retainer plate tight against the lock though so I could easily adjust timing.

-- DW

 

[webbd]

Update

Short version, it's running really well now.

Longer version, one more part needed replacement. The kill switch wire broke right at the amphenol connector to the power pack. After tuning, I needed to disconnect the whole charge coil plug to stop the engine. $4.00 and an hour later, I'd visited the local Evinrude shop and attached a new female connector attached to the wire and inserted it into the plug. The key stops the motor again.

I took it out on the water a week ago Saturday to make some fine carburetor tuning adjustments. All engine speeds worked perfectly except about 1700RPM - 1900RPM. In that speed range, the engine would drop down to firing on one cylinder. It's easy enough to bump it up to 2000RPM, and 2000RPM appears to match hull speed also, so there's a range of throttle at that engine speed.

On cold start, I needed to prime it during start and about twice after start to keep it from dying before it would run smoothly. I assume that this is a warm-up issue, although I may take the timing light to it again.

It ran perfectly all the way up to 5800RPM (other than the above mentioned), but I opted over the holiday week to keep boat speeds down due to higher wind conditions that made it too bumpy to go much faster than 21mph. At 4000RPM, it ran just on-plane at 16mph. At 5000RPM, it ran at advertised cruising speed of 21mph.

Having done most of my work on motorcycle engines, automotive engines, and auto-sourced marine inboard and I/O engines, I was surprised at how tightly synched the timing linkage needs to be. Lesson learned.

During all of this, I saw a "new" Evinrude ETEC at the place I bought my 2nd coil of the year. They wanted $7150. I may have unintentionally ruined some electronics parts or replaced some parts that didn't need to be replaced, but for $300, I have a well-running engine and don't need to spend on a replacement to keep the admiral feeling safe and happy.

-- DW