Evinrude ’57 Fisherman Throttle / Idle Adjustment?

[mondobug]

I got the motor running well on a fuel pump (water pump, carb and gear case also serviced) and I’m satisfied but I’m thinking that perhaps it could be better? It starts and runs just like I remember but it shuts off with the handgrip on “slow” instead of “stop”. A slow, smooth, reliable idle is obtained halfway between “slow and shift”. But can this be improved?

Here’s where it’s at: 90 psi on the top cylinder, 85 psi on the bottom – motor will start and run on either cylinder alone. Points cleaned and gap checked but was not timed with a meter. Throttle gear mesh – handgrip stops on “stop” and stops on “fast” so that should be correct? Runs and idles best with the high-speed needle 1/3 to ½ turn out from closed, low-speed needle ½-3/4 turn out. They’re very sensitive.

Throttle adjustment: The first picture shows the position of the index mark on the cam as the cam first touches the roller when advanced, below “start”. The second picture shows the mark with the handgrip on “start”. At the slowest, best idle, the roller is not riding on the cam. Does anyone think this requires adjustment? Will adjustment make the indexing of the handgrip more accurate? I’m not entirely understanding this cam adjustment procedure (from what I’ve read) so is there a good tutorial?
THANKS!

[garry-in-michigan]

It looks like everything is as it should be. Fasenating plumbing on that fuel pump,

. . . . . 😀

[chris-p]

The throttle shaft should just start opening when that roller touches that hash line. Watch the linkage on the carb attached to the roller. It should start moving when the roller hits the line.

If not, looking at the motor, that brass cam has 2 bolts holding it on. The one on your right, will have an oblong hole, so if you loosen it, it will pivot in and out to make the adjustment.

Don’t worry so much about where the arrow on the tiller grips lines up with. That is a guide at best, and not gospel. They are never lined up perfect.

After running them for a while, you don’t even pay attention to that anymore.

[fleetwin]

Yeah, don’t be concerned about the slow/stop indicators on the throttle control, rarely accurate. Do not try to compensate/adjust by changing the throttle cam pick up.

[mondobug]

quote Chris_P:

Don’t worry so much about where the arrow on the tiller grips lines up with. That is a guide at best, and not gospel. They are never lined up perfect. After running them for a while, you don’t even pay attention to that anymore.

Thanks. I was thinking the same thing but there’s a lot of grip travel between slow and stop – and I thought it should at least keep running on "slow". Maybe I’ll try to get the cam adjustment a bit closer to ideal.

One more Question:

Does the position of the magneto plate matter when checking point gap?

I used the cam to roller alignment to check them because I couldn’t find the info. I replaced coils, points and condensers some years ago and haven’t used the motor much since so I didn’t remove the flywheel this time – so I wasn’t sure if I was getting the maximum gap with the limited access of the inspection hole.

[david-bartlett]

Mondo,

The rotation of the mag plate will make the point opening smaller or larger as it rotates around the high spot of the cam, so yes it matters if using a feeler gauge. If using a timing jig, you will be moving the mag plate as you adjust things.

This probably confuses the issue more than clarifying it.

[chris-p]

I assume you are using an 020 feeler gauge? If you use the access holes on top of the flywheel, without removing the flywheel, it will position it for you where it should be.

If you remove the flywheel you set the rubbing block of the points against the key on the crank shaft taper, then set to 020.

I always remove the flywheel myself. I hate working through that little hole! I always like to dress them, and inspect everything as well. Popping the flywheel only takes a second, and gives you much more room to work. Just my 2 cents.

After setting them, always dip paper stock, business card, etc… in acetone, and run that through to clean them for best spark.

In regards to getting your idle lower, what helped me best achieve this was by using a timing fixture and buzz box or meter.

It helps you get the points to fire exactly 180 degrees apart, which really helps in smoothing out a low idle. Only Spider man could achieve this with the feeler gauge alone.

[mondobug]

quote david bartlett:

Mondo,

The rotation of the mag plate will make the point opening smaller or larger as it rotates around the high spot of the cam, so yes it matters if using a feeler gauge. If using a timing jig, you will be moving the mag plate as you adjust things.

This probably confuses the issue more than clarifying it.

quote Chris_P:

I assume you are using an 020 feeler gauge? If you use the access holes on top of the flywheel, without removing the flywheel, it will position it for you where it should be.

If you remove the flywheel you set the rubbing block of the points against the key on the crank shaft taper, then set to 020.

I always remove the flywheel myself. I hate working through that little hole! I always like to dress them, and inspect everything as well. Popping the flywheel only takes a second, and gives you much more room to work. Just my 2 cents.

After setting them, always dip paper stock, business card, etc… in acetone, and run that through to clean them for best spark.

In regards to getting your idle lower, what helped me best achieve this was by using a timing fixture and buzz box or meter.

It helps you get the points to fire exactly 180 degrees apart, which really helps in smoothing out a low idle. Only Spider man could achieve this with the feeler gauge alone.

Thanks guys. I don’t rely on point gap alone either. Back when did all the magneto work, I’m sure I did the timing, probably with a light bulb soldered to a battery because that’s the way I did dirt bikes. This time around, I just wanted to check for any changes – and I probably forgot about some of the things I knew about the motor back then. And I did the business card trick – only with CRC Electra-clean.

Question:
There are two notches 180 degrees apart on the bottom edge of the fly wheel (that can’t be easily seen on the side of the flywheel).
These are timing marks (one for each set of points) correct?

There are two vertical lines (close together) cast in to the mag plate, just left of the front. When a flywheel notch is between these two vertical lines, the light should go out – and both sets of points use these two same lines. Is that correct?

THANKS AGAIN!

[mondobug]

quote Chris_P:

The throttle shaft should just start opening when that roller touches that hash line. Watch the linkage on the carb attached to the roller. It should start moving when the roller hits the line.

quote fleetwin:

Yeah, don’t be concerned about the slow/stop indicators on the throttle control, rarely accurate. Do not try to compensate/adjust by changing the throttle cam pick up.

Good tips. Thanks. When I watched for movement of the main linkage today, instead of contact with the roller like I was doing, the mark was right on the money so I didn’t adjust anything.

[mondobug]

When I first stated it up yesterday, I was getting a lot of surging in the mid and high ranges indicating an air leak. This eventually improved to barely noticeable, like a transplant patient becoming acclimated to her new appendage.

Today, after I buttoned everything up, I think it ran even better. Slower, smoother idle and no surging at all. I think I may not have had the needle valve packing tight enough – as I was operating them knob-less and they felt OK. Anyway, I think it runs great now.

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