WOT roller setting

[JerEazy]

59573B 1975 50hp

long story I won’t get into involving someone “helping” when the engine suddenly died during docking and wouldn’t restart. This “mechanic” made multiple adjustments to timing and the carbs that got the engine started and let me limp back to the dock. But didn’t solve the problem (which, from what I found back on the trailer, was a sheered or lost pin that held the timer base arm set in the retainer causing it to move a lot)

so ive got back through and re did a carb link, set up and adjustment along with idle speed and set the idle timing and Full advance timing back to spec as per the manual. Now she’s idling fantastic and revs just fine in the water. No complaints as to how she runs really. But I want to make sure I did one thing right.

The manual says I can have .000 or .020 clearance at wide open throttle between the roller and the linkage. But the arrow in the picture of the manual doesn’t exactly say where that clearance should be from. See the attached picture. It’s set so that at WOT the roller is set on the linkage’s “furthest” or most wide open space. But should that .000 or .020 be from the very end of the linkage? That flatish spot? I’m probably over thinking. But want to make sure.

Thank you

 

[Aaron Huyser]

this video may help you I think you talking about the air gap beween the throttle cam and follower roller. see video

https://www.youtube.com/watch?v=qigy9Ryha2A

 

[JerEazy]

Great video! Thank you.

Its slightly different than my model - but I get the theory.

i appreciate the help

 

[jimmbo]

Idle Timing? No such thing. The timing is simply retarded until the engine is idling at the correct speed

 

[JerEazy]

Sorry - not sure what you mean?

Timing should be 3 BTDC +\- 1 at idle according to the manual

 

[racerone]

Mis-understood------Idle timing is where throttle opens up.--------Information in post #4 is " spot on ".-----Idle timing on your motor is not set like the timing on grandpa's 283 Chevy small block !!!!

 

[JerEazy]

Well sadly both of your responses are going over my head.

manual had me connect a timing light to the top cyl plug wire and idle the engine, and turn the idle screw until 3 +\- 1 was seen at idle.


So, that to me means setting the idle timing. I apologize if I’m using the wrong terminology.

 

[racerone]

Idle timing is the point where throttle plates open up !!!-----If anything it is a carburetor adjustment.-----Only the MAXIMUM timing advance is something that is set.------Do not adjust timing on your motor if you do not fully understand the consequences.

 

[JerEazy]

We've gone a bit away from the topic. But, you just called it idle timing. Which is exactly what i called it. So i'm really not sure where the confusion is coming from. I'm fairly certain everyone knew what i meant. "Making the necessary adjustments so that the timing is correct at idle." I do understand it is not the same as setting an old engine because i'm not turning or adjusting a distributor or other timing mechanism. I'm really not sure why the terminology is an issue.

If i rephrase will it satisfy you and perhaps we can get back to the topic at hand if you have any light to shed on it?

I adjusted the idle screw that is attached to the linkage to adjust the idle RPM and idle timing to advance or retard as necessary to reach the correct factory spec at the correct idle speed. Which according to the manual is 3 deg BTDC +/- 1 at (i'm going from memory on this part) 750 +/- 25 RPM. I did this adjustment along with the low speed idle screws to ensure proper adjustment.

The full advance timing is set in a similar fashion. The adjustment of a stop screw (along with a lock nut) stops the timing from advancing too far or not advancing far enough. correct setting. which is 19 deg BTDC +/- 1. 1 full turn of the screw will adjust 1 degree.

Thanks again for your help.

 

[racerone]

Good luck with the motor.

 

[JerEazy]

Thanks - almost done with the project boat and putting it up for sale.

you and other members of the site have been a wealth of information.