Tech Tips from the CCOA Tech Advisor

By Russell Kiler | Member # 12926

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Question from Steve J
Can you tell me more about a flywheel puller you made for the OMC scooter engine?

Tech Answer
Steve, the picture shows the puller made from a scrap piece of 3/8-in. thick aluminum. Aluminum is easier to work with for me. The hole pattern was designed by tracing it from the kick starter three-hole flywheel pattern. Drill the three-holes out to 3/8-inch. A little more room works better with the 5/16-18X1.5″. Hex screws. Use flat washers with these oversize holes and you won’t have to be dead on with their location. The large hole in the center fits very closely right up to the crank threads. I used an 11/16 drill and a file to achieve a close fit (about .700 IN). Aluminum helps here too! The three tapped holes give a place to store the screws and flat washers. It was easier to tap using a slightly oversize tap drill from normal. Tighten the screws evenly and gradually to remove the flywheel from it’s taper.


Question from Dan H
I wrote with questions about my Step-Thru (I thought it was a Model 60). I asked a lot of questions about carburetors and different things. You suggested I purchase some of the special issues and the engine book by Jim Frederick. I have since determined that my scooter is a Model 54 and not a Model 60. I purchased two special issues from Bob Cantrell that provides a lot of info on both models. Quite informative! Thanks for the help…the books are a good buy!

Tech Answer
Dan, I can almost always suggest that a member, especially a new member, obtain material covering their scooter. And you quickly learned what scooter you actually
had. I find that many people are not aware of the many different Cushman models. Part of the fun is learning about your scooter and others.


Question from Chris F
I have a Model 735 Gasoline Golfster with Terra Tires. I would like to go with a standard golf tire if possible.

Tech Answer
The Terra Tires were very wide with low pressure iron and were extremely heavy. They were also extremely hard to work on as they were nearly a foot wide. I am guessing that replacement tires would be near impossible to find. Most of these golfsters were sold equipped with more conventional wheels and tires. The front fork is special for these wide terra tires but can work with other tires. I suggest you study your golfster and compare it with ones having the more regular tires to determine which items you need to change. Manuals, hubs, rims and tires are listed for sale occasionally. Check with Robert Cantrell for a manual, too.


Question from Paul O
I am new to Cushman and a friend purchased a Model 50 scooter (we think) with what was supposed to be a NOS engine. We can’t get it to run. How can we tell if it is getting gas to the cylinder?

Tech Answer
WOW, Really? We haven’t seen NOS engines for years. First, make sure you don’t have a kill wire going to ground. Try to start it, then pull the plug. Hold the plug in one hand and smack it and your hand into a clean piece of paper in the other hand in a clapping motion to see if any fuel is to the plug.

Follow up Question from Paul O
Now we learn that supposedly it was a NOS short block but we found that the head was warped. It was equipped with split washers under the head bolt nuts with no flat washers and had a blown head gasket. The kicker has oblong holes and the flywheel key is loose on the shaft and now they tell me that this is normal. Really?

Tech Answer
Have you considered wringing the neck of someone? No, a loose key is not normal but does happen with poor assembly etc. Your findings show the worst of people messing in our hobby. I want to use your experience to illustrate to our readers the importance of checking with someone knowledgeable who has worked with Cushman scooters prior to purchase if you can.


Question from V.K.
Your flywheel puller looks ok but I tried one similar to that and damaged my flywheel. I think this might have happened because I tightened the nut with an impact gun. I suggest that after snugging up the screws one could slip a piece of tubing over the kick starter bushing against the plate and give it a sharp blow with a hammer if it didn’t readily pop off.

Tech Answer
I appreciate your writing and agree with your idea if reasonable tightening doesn’t move the flywheel. The flywheel knock-offs work well but not everyone has one. You can order one from Carpenters Reproductions for $17.50.


Question from a pair of truckster nuts at the Portland Meet
Some people think that the early 4.43 – 1 axle ratio in the truckster will give a greater speed than the 4.71. Will it?

Tech Answer
When Cushman first manufactured the aluminum cased differential (rear axle) the highest speed ratio available was 4.43 to l. This ratio was discontinued and replaced with the 4.71 to l ratio. The ring gear teeth number 31 on the 4.43 ratio and 33 on the 4.71 ratio. The high speed ratio was used in on-road vehicles like the Police model and the on-road flat bed Truckster. Other slower ratios were used for other on-road models and turf and industrial models. These ratios were 6.5-1, 8.25-1, 10.25-1 and others for golf, industrial electrics and mowers.

The 4.71 ratio remained in use replacing the 4.43 early on and is still used today. Sewal Gear Manufacturing Company of Saint Paul, MN produced the worm and gear sets for Cushman. The 4.71 ratio was a smoother working unit and perhaps longer wearing and more uniform in manufacture.

To ask if the 4.43 is faster would bring the answer yes, but only based on numbers. Theoretically it would be faster but many other things say it might not be. Tire size, new vs old tires changes the overall ratio too. I think the standard Trucksters vary in top speed a couple of miles per hour already. The tiny difference from the rear end ratio is negated by more or less RPM on your tach or a little wear and tear on your engine and of course body style and weight. The on road Trucksters using this axle were governed to run 39 MPH because of various regulations and guidelines for this type vehicle. The 4.43 is certainly not worth the extra money some people are willing to pay for a two and one half % increase in numerical ratio.


Question from Ken S
Hi, Can you tell me what year this Cushman scooter is? I don’t know the year but that is my dad driving, my little brother in the middle, and me on the back. Every summer we would vacation at Geneva-on-the-Lake, Ohio and the hotel where we stayed rented motor scooters. The black and white snap shot is not dated but it got me to thinking that restoring an old Cushman could be a fun project.

Tech Answer:
Thanks for the interesting picture. I say it is a 1946 or early 1947 Model 50 Series Cushman. You might also take a look at the scooters CCOA members have for sale in the Scooters & Parts section.


Question from John W
How can I tell which year Eagle I have? It has welded floor boards. I might have a 762 model but how do I know for sure.

Tech Answer:
The first thing you should do is to purchase the Special Issue of the Cushman Club of America magazine that covers the Barrel Spring Eagles. It is just excellent and you could learn you have a great old Eagle. Order the Special Issues from Robert Cantrell at 207 Cedarberry Dr., Blue Eye, MO 65611. You can order all eight of the Special Issues or just the Barrel Spring Issue. If you have a Model 760 it will be a single speed having no transmission. If you have solid foot pads you could have a scooter of 1952 or earlier. The flip up pad started in spring of 1952 we think. Get that Special Issue as there are about ten more things you want to learn about “Springer Eagles”


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