A Cub Comes Out Of Hibernation

Belt pulley

The belt pulley and original exhaust valve serve to show the general rust and corrosion that had to be battled in getting this engine back into operation.

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1841 Pinecove Drive, San Luis Obispo, CA

This tale has its beginning about 3 years ago in the lab at the college where I teach electronics. It was during a break and I was busying myself cleaning the place up a bit. Gabe came in. Now Gabe needs some introduction but I'm not going into detail at this time for he needs more than just an introduction; he needs a whole story. Perhaps I will come up with that one at a later date. For now, suffice to say that Gabe is the local 'Mr. Engine' around here. He has the unique talent of being able to see just what needs to be done to make a recalcitrant engine run. He can visualize what a missing part must look like and, most of the time comes up with something approaching the exact duplicate. Mainly, for the purposes of this narration, he is my main engine scout. I have several engines and about half of them came, one way or another, through Gabe.

On the day in question, Gabe showed up at the lab during my break and said, 'You still looking for a small engine?' I responded that by now he should be well aware that I was always looking for a small engine. 'Well,' he said, 'I think I've found one you will be interested in'. 'Oh yeah', I said, 'What have you got?' 'Well', he said, 'I haven't actually got it, it's just like I know where it is.' 'O.K.' I said, 'Where is it and what is it?' So he said, 'I just wanted to know if you were interested first before I got myself involved.'

If you think all of this conversation is getting boring it's just because you don't know Gabe. You have to do a lot of verbal sparring with him before you get down to brass tacks and then you must be wary lest the brass tacks turn out to be ten penny nails. So I decided to go along with the drift of things and find out what was going on in his head. 'O.K.' I said, 'I'm interested so what have you found?' 'Well', he said, 'this guy has two engines out in a shed, they've been there for years but they've been under cover all the time. One of them is big, maybe 5 horse power and I've got my eye on that one but the other one is small and I think it is just what you've been looking for.' 'So O.K.', I said, 'What is this little gem anyway?' 'Looks to me like a Cushman Cub. If it's not, it's something very much like it and about the same size. Thing is,' he said, 'this is really a clean engine that looks like all you need to do is fuel it up, crank it and away she goes.'

'How much is it going to take to liberate this paragon of machine-hood?' He quoted me a figure that was a little higher but not that far out of range of what I'd had to give up for some other more or less seedy engines I'd already found through hm. 'So,' I said, 'Do you think it's worth that much?' 'Oh yeah,' he said, 'I'm telling you this is really a clean machine you don't have hardly anything to do to it to have it ready for the show on Memorial Day.' (Our local crew get together on Memorial day each year and hold a fun time old engine show over in Cayucos at a place called the Weigh Station because that's what it used to be in old days. Now it is a restaurant and the owners are very gracious about sponsoring this annual event in their parking lot.) I thought it would be really great to have a new engine to show that year and since it seemed like this one would not be too tough to get ready, I peeled out some bucks and turned them over to Gabe.

A couple of days later, Gabe showed up with the little gem. I immediately realized how it was that he was not sure whether it was a Cub or not. Through all the rust it was hard to be sure that it was actually an engine! 'This is the Cream Puff engine that you described to me?' I demanded. 'Well' said Gabe, 'It was pretty dark in that shed. Anyway, it's not as bad as it might seem, that engine is all there.' 'How can you tell? For crying out loud, the only thing you can be sure of is that all the rust is there,' I said. 'Yeah,' he said, 'but look at it this way, if there is rust, there had to be something underneath to support the stuff.' 'You told me all it needed was gas and it was ready to go' I said. 'Well, I guess I was wrong' he said. 'And I'm supposed to have this thing ready for the show? You've got to be kidding.' I said. 'Don't feel picked on,' he retorted, 'the other one is the same way and I'm going to get it in shape in nothing flat, just you watch.'

By this time I had begun to pick and poke at the lump of rust that sat there on the floor and, as the chunks of mud broke free and the scales of rust were brushed away, it appeared that indeed, this was a Cushman Cub and, moreover, it was, at least essentially, all there. Trouble was everything was stuck firmly together with that world's greatest weld, 'iron oxide'. The valves were frozen in their guides. The piston, if there was one in there was seized fast. There was a wierd growth in the mouth of the mixer which was the only part of theĀ  engine except for the mag that was not iron but some kind of zinc or pot metal. There stood bravely above all of this brown crud the square box-like structure that was unmistakeably a WICO EK. It was not brown, it was green. I said, 'Gabe, you rascal, you have ripped me off.' Not at all,' he said, 'you can make a really neat little engine out of this, and I've got another Cub for a parts engine that you can have.'.'O.K., O.K.' I said, 'let's see how things turn out before I wring your neck.' Which is laughable in the extreme, I probably couldn't get my belt around Gabe's neck, let alone my hands.

Don't get the wrong idea about Gabe. He is not a dishonest guy. You could trust him with your wallet or your wife but not your knife. It usually goes something like this: You'll be working with Gabe on some kind of a joint project and he'll ask to use your knife. Instead of giving it back to you when he is through, he'll slip it into his pocket. If you are not alert and don't demand it back, he will hang on to it until he has shown practically everyone in the county that he has your knife. Then he'll give it back to you. But, keep your wits about you because in thirty minutes he will be working the same scam all over again or something like it. You see, that's just the way Gabe is. On the other hand he'll give you anything that he's got that you need.

With Gabe's assurance that he would help whenever I got stuck, I was mollified and, I have to admit, I was rather taken with the compact little engine. Gabe was right in that part at least, it was just about what I had been looking for in the way of a small engine. A considerable improvement over my Sattley that weighs in at about three hernias. So, shortly, work got underway. The engine had to be stripped down to all of it's individual, constituent parts. Nearly every piece had to be sandblasted. Valves had to be driven out of the guides with a mallet. The internal mechanisms were in relatively good shape, having been more or less preserved in a black gooey substance that resembled more than anything else the material I use to coat my asphalt driveway. I was worried about freeing up the piston but that turned out to be a minor matter it was merely glued in place with this tar-like substance. A little solvent and it came out O.K. The rings were welded into the grooves with tar and carbon and rust and varnish and stuff. I spent an entire afternoon freeing up the rings, cleaning the grooves and fitting a replacement set of rings that I made Gabe produce for me.

I swabbed out the cylinder about a hundred times with every solvent I could find that wasn't toxic and a few that I had some doubts about. It finally began to look like an engine cylinder. I worked it over pretty good with a hone and miked it out. It had some little taper but I thought it to be in tolerence and decided to stay with it rather than go for a rebore and the accompanying complications with pistons and rings that would necessarily follow that action.

The water hopper was half full of sand, gravel and broken glass. It looked like this engine had spent some time on the bottom of a stream. I had the devil's own time getting all of those bits and pieces out of the castings. Some bits refused to come out through the top yet they were too large to fit through the water channel holes leading to the head. In some cases I had to resort to using long nose pliers to break the rocks or glass pieces into small enough parts to fit through the orifices. This, and flushing with a strong flow of clean water eventually cleared the engine of that foreign matter. Then I had to make a new head gasket using the old damaged one as a pattern.

Dismantling and sand-blasting was done to see what good shape everything was actually in. The engine had come apart without breaking any bolt, nut or screw. The only items that were missing were the cover for the exhaust valve tappet and the lock screw for the mixer. Everything else was there. Fortunately valves from Gabe's parts engine fit just fine which is a good deal, because virtually nothing else from that engine fit. The condition of the engine didn't leave a clue as to what the original color was. From a scrap of the parts engine we were able to determine that a grayish blue was in order. I found a paint chip that matched almost exactly, bought the paint and painted all of the parts. When the paint dried it turned out that the finish was more on the blue side than on the gray side. Not to worry, that's the color this particular Cushman Cub is going to be, a least for a while.

At this juncture in the restoration game, fate stepped in and the press of business kept me away from the project for almost a full year. I was out of town over the Memorial Day weekend and missed the show entirely that year. The painted parts got distributed over a fairly wide area though all in the same room. When time once more permitted me to involve myself in old engine activities and spurred on by a particularly enjoyable two day session at the Cayucos show over the Memorial Day weekend the following year, I decided to round up all of the pieces and see if I couldn't get the little Cub put together. Fate smiled. I found everything in the storeroom, loaded it into my car trunk and hauled it home. I had, up to this time, been trying to work on the project in my 'spare time' in the school lab. This was a mistake because everyone always knew exactly where I was and interruptions were more a part of the activity than was the engine project. With the engine at home during vacation, I could work without fear of being called to the phone or asked to go to the Dean's office for this and that.

It took two days to get everything bolted back to where it was supposed to be. Once it was reassembled, with the new blue paint job the engine began to look as Gabe had predicted some months previous, 'Pretty Neat'. The question was, could it be made to run? The mag was checked for spark and did a good job. Actually the mag was the cleanest part on the whole engine and seemed to be in good shape from the start, though it took a lot of elbow grease to get the brass to look like brass instead of an old army, OD paint job. Anyway, the ignition timing was set in accordance with the manufacturers recommendations. The punch marks on the valve timing gears had been checked at the time of reassembly and the valve tappet clearance was set to specs. The oil pan and the gas tank were serviced and, with a brisk rubbing of hands I prepared to make the thing run. So I cranked it and nothing happened. I rechecked and reset the timing and the valve clearance. Still nothing! Once in a while, during the cranking process the engine would fire but not with anything you could call enthusiasm. It would never carry through even to a second cycle. Oh well! let's readjust the fuel needle valve and try again. Now I guess I've got the fool thing flooded. So, once more, all of the adjustments were reset and still the engine refused to run. I remembered that someplace among my bits and pieces I had a spark plug that, although it looked good, did not operate when under compression. That must be it, I'd put the bad plug into this engine. So I borrowed a plug from a friend's International Harvester that I knew had been running. With this plug installed in the Cub I tried again. Still the same. The engine would not run! I began to doubt those things I used to consider to be facts about the theory of operation of the internal combustion engine. I remembered reading in 'Reflections', some comment to the effect that the timing marks on the valve gears could be set off a bit and the engine could run even better sometimes. I began to wonder...may be I needed to open the engine again and set the valve timing to a different position? But set it where? It was already where all of the theory said it should be??? Then, as I lay in bed one night a thought came to me. Maybe I was looking at the wrong end of the problem. I could have some carburetor problem here. Or, to be more accurate a problem with the 'mixer'. When the engine was reassembled, I noted that the pot-metal casting of the mixer seemed to have shrunk over the years and it threaded into the head of the engine in a very loose fitting manner. So maybe, just maybe, the engine was sucking air around those loose threads and not drawing through the mixer throat as it should do? It took a good bit of self discipline and contemplation of the things my wife might say to keep me from jumping out of bed right there and then and rushing out to the garage to try this new theory. Also it was well past midnight and I might have incurred the wrath of the neighbors, particularly if I was successful. So I went off to sleep determined to get at the job first thing in the morning.

First I had to find some teflon tape of the type that plumbers use on pipes to seal the threads so they would be airtight. When I checked the tightness of the threads, I found that if I screwed the mixer in as far as it would go it ended up on its' side and the gas line could not be connected and the throttle linkage would not connect properly even if the air flow in that position could be O.K. While working with the mixer I discovered that the face of the air valve which I had taken to be some sort of bakelite was actually practically petrified leather. Moreover, the seat of the valve was pitted and scarred so that proper seating was impossible even if the valve had been good. I rigged up an emory paper disc glued to a small brass gear on a shaft. The gear, another piece out of a junked radio, was just the correct diameter and the shaft fit the chuck of my quarter inch drill. With this rig I carefully restored the valve seat in the mixer so it was smooth and flat. The valve itself was more of a challenge because not only was the leather hard and brittle, the nut holding the entire assembly together was firmly rusted in place. I put the whole business to soak in a pan of penetrating oil. But impatience goaded me into constructing a whole new valve assembly. I found a large washer about one and one quarter inch in diameter and drilled out the center hole to the proper diameter. Through this hole I inserted a brass bushing that was originally intended as a through chassis shaft bushing for a radio set. I faced the washer with a leather disc cut from the tongue of an old shoe using a smaller washer to hold it flat against the larger washer. I had a valve that was not too far from the original and, as it turned out, worked quite well. I subsequently rebuilt the original valve assembly using a piece of leather more closely resembling the manufacturers version. I never did get the rusted nut to thread off, and had to cut it off and replace it with a new one after I chased the threads with a die of the proper size. The engine can't tell the difference between my homemade valve and the rebuilt original, but I put the original in for some degree of authenticity. After all I had taken some liberty with the paint job. I applied about half a roll of teflon tape to the threads of the mixer just outward of the set screw hole and achieved a reasonably good air seal when the mixer was aligned in the proper, verticle position. After the linkage and gas lines were reconnected and with the first crank the engine actually tried to start! Oh ecstasy! After some experimentation and tinkering with the setting of the needle valve and the throttle adjusting screw and some more cranking, I had the little engine up and running. It purred like as kitten, responded to the adjustments with spirit. But there was more noise generated by the crank-case breather cap and the mixer air valve than by the engine exhaust. I let it run for about an hour and just stood there watching and listening.

The intake valve made a funny snuffling sound like an old sow rooting for acorns burried shallow. I concluded that the valve was vibrating in the guide due to excessive clearance brought on, no doubt, by the forceful removal with a mallet of the old valve and clearing rust in the guide. I increased the spring tension but to no avail. So the head had to come off again and the valve problem needed to be solved. I miked the valve stem at .308 inches and the guide at .311. I dug around in my collection of bits and pieces and turned up an NOS valve for a model A Ford which looked like it might solve the problem. It could not be tried in the valve guide until I cut off the flared end. So I cut it to length and dropped it into the guide. The fit was almost perfect. I had to drill a hole for the keeper and all was well. I had anticipated the need to grind the head a little smaller but seating was very nearly perfect and after slippng it into the seat with a little compound I put the head back together and re-installed it on the engine. After two revs with my hand choking the inlet to the mixer the engine started and purred as before. Most of the valve chatter was gone though it still showed a tendency to make that chattering sound. The leather faced air valve makes more noise than the intake valve though and I'm, leaving it as it is for now. I will probably, one day, need to drill and shim the guide to get a more perfect fit-one day.

I put the decals on the water hopper and as can be seen from the picture, I've got a Cushman Cub that is very nearly in factory-new condition and appearance. I am proud of myself because I usually have to call on Gabe for help to coax a reluctant restoration job to get going but this time I was successful all on my own. But I am proudest of the little engine for the way that it responded after so many years of neglect.

One consideration that merits recognition here is the fact that had I continued my restoration efforts without interruption, I would have had this little Cushman Cub ready for that Memorial Day show just as Gabe had predicted when he first dragged the pile of rust into my lab. Gabe is not often wrong in his assessment of old engines.

In any case, there is no doubt about it, this is one Cub that has definitely come out of hibernation! Now, just wait for Memorial Day 1988!