There are plenty of good articles in the Newsletters about overhauling Whizzers, and there is not much point in me re- inventing the wheel. But here are some things that can get you in trouble if you aren’t careful, and they do bear mentioning.

  My worst nightmare is to trash something that a competent person might have fixed, not only for the money, but when these are gone, there are no more. To that end I will not run an engine if I haven’t looked at the bottom end, especially if it looks like the engine has been apart. One of my buddies bought a Whizzer from a guy who said he was a machinist and had "fixed the rod". The rod was poured full of Babbit metal, and had about 1/8 inch of slop in it, and was in backwards. The crank looked like somebody had worked it over with a grind stone. The journal was burned blue!!!! I’ll take my machine work elsewhere, thank you.

   If you are not a very competent mechanic, and have the urge to fool with small engines, go down to the local recycling yard and buy a couple of junked lawnmowers for five bucks each. On any given day, you can find a dozen, and probably six of them can be made to run by replacing the shear key in the flywheel , setting the points, and replacing the water in the tank with gasoline. Four need the crankshaft straightened. Two are rusted away. I’ve seen few worn out engines, unless somebody ran it out of oil. Mostly, people hit something with them, and shear the key, and then the magneto won't fire, or leave 'em out in the weather, and the gas gets water in it. Either that or they dry out and the fuel pump in the carburetor quits working. If you bugger ‘em up you can go get another, and leave the Whizzer to someone who can do it right. There are a number of competent people who can rebuild your engine to like new condition if you don’t destroy it trying to do it yourself first..

  If you are a competent mechanic, first get a copy of "WHIZZER SERVICE FACTS" and of Bob Baker’s Newsletters. They are indispensable. Read them both. It will save you money and much aggravation. The Whizzer is not a Briggs and Stratton lawnmower engine, and has its own quirks and vagaries.

   The engine can be disassembled with hand tools. Leave the hammer alone. Pull the side cover off. If the Phillips head screws won’t come out, drill just THE HEADS out. Don’t use a hacksaw or a chisel, you’ll wreck the side cover. A little heat may help. There should be a spacer on the end of the crank, kind of a "Q" shaped washer about one inch inside diameter. There is another spacer on the camshaft. Both these are necessary. If they are absent, find a set before you run the engine, or the timing gears will chew up the side cover. Be aware that there are several thickness’ to govern end- play.

   Look at the rod cap. The bolts should be safety wired. If they are not, somebody has been into the engine, and I would probably tear it down right away. I found one set of inserts in backwards, and another full of shims. One had inserts homemade from "OILITE" staked in with brass pins. If the bolts are wired, shake the rod. If it is loose, tear the engine down. A thrown rod is a painful occurrence.

   If you decide to tear down the engine, remove the carburetor, and the coil first, and then pull the flywheel. The bolt is a Left- Hand thread (or is supposed to be). After the bolt is out, drive two hardwood wedges in behind the flywheel at opposite points to pop it off.

   The crank could be either insert or needle bearing type. If it is a one piece forging it is an insert crank and is SAE. If you can see the crankpin where it is pressed into the sides of the crank, it is a needle bearing crank and the bolts are 5mm metric. Watch the rod cap bolts on the insert crank. There is a long one and a shorter one by 1/8 inch. The short one goes in the blind hole (top). They are special bolts too, and not just 1/4 inch cap screws. Watch how the cap and rod come out. They only go in one way. If you assemble the rod backwards or interchange the bolts, you’ll destroy the rod.

   Pull the head. Take off the coil, carburetor, and flywheel. The easiest way to get the piston out is take off the jug from the crankcase. Four nuts at the bottom and the jug comes off. Lift it off the piston and rod. If the piston is stuck fast, remove the whole jug, rod , and all from the crankcase. Soak it in WD40 or PB Blast* for a day or so, then push the piston out the bottom. I put one cylinder in the barbecue grill for a half hour before I could get the valves out.(That won't work for the piston. Aluminum expands faster and farther than cast iron) Pistons and rings can be had. Inserts are being reproduced. Cylinders are harder to get. Cranks and rods are the hardest to find. They are valuable.

  * (A friend of mine who is an excellent machinist says that if you can’t get something out, soak it in hot lard..... I think I’d do that outside.)

   The crank pushes out the open side of the engine. Leave the left side crank bearing housing alone. Take the valves out. There is an intake and an exhaust valve, and they are not of the same material. If you interchange them the exhaust valve will burn up. The exhaust valve may be lettered "x" or "ex" at the underside of the head but you have to look for it.

   Clean everything with a good degreasing solvent....NOT GASOLINE. Dry it off. Get out your "Service Facts" and inventory the parts

A "J" Engine

   Mike the crank and the rod bore. The crank is .999 inch and the rod is 1.0934 inside. Both must be perfectly round. If they are out of round, have them ground and re-sized. Be careful, this is critical and they are irreplaceable. Undersized inserts are available. Make sure the rod cap has not been filed down. Check the wrist pin and bushing. Assemble the rod bearing and crank outside the engine and check it for play.

   Mike the cylinder and piston. The standard bore is 2.248 in. Pistons and rings are available. If you need a new piston and rings, buy them first and have the cylinder ground to match. Re grind and seat the valves. New guides can be had if need be.

Let’s not do this "on the cheap". Saving a buck might cost you an engine.

   Go easy with the carburetor. They are pot metal and strip and break easily. If you don’t have to take out the metering jets....don’t!! Pa says "If it ain’t broke, don’t fix it". Also, don’t clean the passages with a drill. They are calibrated, and if you ream them the carb will never be right.

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