CD-11 acceptable parts wear

[skanders01]

Restoring 4 1954 5.5’s…hoping to get at least two if not three running out of the four. Obviously facing the same questions that any restoration project manager/laborer has to answer. For now, the first significant evident wear is showing up on the throttle cam and cam follower arm. Wear is significant on all four motors. Most of the wear is at the "mid-throttle" range on the cam and maybe only about 15% of the way through the shaft. I would like to replace the pieces but not sure it would be worth it as the only effect that I can see is that more twist of the throttle would be required to gain RPM than it would taken with new parts. I see on parts lists that the follower arm was later replaced with a roller.

Complicating the decision is the fact that I am having difficulty finding replacement parts so I am not sure of the cost to assist in the decision. I will keep looking for replacement, maybe I can find a roller follower/cam in newer models that might be more readily available and less costly that would fit.

Has anyone else come across this situation? Anyone see any other issues than less responsive throttle speed increase rate per degree of tiller handle rotation? My thanks to any of you out there who may be of help with this question.

Kyle Anderson
Trempeleau, WI
skanders@triwest.net
920-764-0501

[fleetwin]

Well, not quite sure I am properly visualizing your throttle cam set up….
But, wear will cause the engine to run a little rougher/richer in its midrange. I’m not sure you can substitute the newer style roller parts on the older engines without creating the opposite effect…
I would get the engine(s) running first before worrying too much about this wear, you may not notice much of a running problem at all…
Post pictures to help us see what you are describing.

[chris-p]

VERY common on them. Just adjust the cam, to compensate for the wear. You can loosen the right side (looking at front of motor) screw under the cam. The hole there is oval, to allow for adjustment. Adjust it, so that the throttle just starts moving when the arm is aligned with the hash mark on the cam.

I have never tried installing a roller on models that simply had the arm. Perhaps there is enough room for adjustment.

I used to simply pull from donor motors, but my stockpile of them is thinning. You could sleeve the bar, or simply make a new one. Sleeving over the wear is likely the easiest solution. Im not a pro welder, not sure if you could add a drop of weld there, then file smooth.

[frankr]

The only real critical area would be just as the cam follower contacts at the mark. And of course that is adjustable. Beyond that, and before WOT, wear would be noticed as running rich at speeds where the wear is real significant. Actually, I don’t remember ever seeing that as a problem. I’ve seen a number of them where the follower actually wore a notch in the cam at WOT position. You might want to deal with that situation

[amuller]

Am not sure what difference wear on the follower arm would make, as long as you adjust things, as the effect would be pretty constant over the cam travel. On the other hand, localized wear on the cam, from lots of running in one position, could alter the spark/throttle ratio at that point. You could build up the low spot or dress the rest of the cam down to match it. You might also look at how loose the mag plate is.

[skanders01]

Wow, thank all very much for the feedback!

Finally found one site with availability and pricing, YIKES. , After the information provided to my one/first post, I can already be the poster boy for the value in being a member of this organization. My membership costs have now been paid at at least 5 times over. Your help just saved me over $200 in cost of new parts.

Feedback was awesome, completely understood, and options provided, again, well worth the price of admission!

Kyle Anderson
Trempeleau, WI
skanders@triwest.net
920-764-0501

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