When Will The Madness End - Two (or Four) New Projects, Wisconsin AB and Possibly AKN Engines

I have tractor projects coming out of my ears and what do I do? Buy two new projects. Oh boy. At least they're small projects, and they were too cheap to pass up. Ten bucks for two Wisconsin single cylinder engines.

I've started working on one engine already (the left one in the photo above) and I found out it's a Model AB by measuring the bore and stroke (when I had to take the head off due to a stuck valve), which is 2-1/2 x 2-3/4 (dimensions for a model AB engine), and it makes a whopping 3 horsepower at 2600 RPM according to the great interwebs. The internet also says the AB was made between 1936 and 1949, so this engine is a gen-u-wine antique.

Both engines are missing their engine tags so it's a bit of a guessing game to know what model a Wisconsin engine is unless the head is removed. Measuring the bore and stroke is the most suitable means of figuring it out.

A cursory once-over revealed the carburetor choke and throttle plate are stuck. I got those freed up only to find out the governor rod and spring to the carburetor are missing. I'll need to make something. Then I found out the exhaust valve is stuck open, so I had to remove the head. Peeling of the onion has begun.

I had to buy new grade-8 bolts for the head, as the ones that came on the engine were too soft and wouldn't torque down to the 16 ft-lb specification (technically, 14-18 ft-lbs).

I'm not quite sure how this happened but one of the four magneto cap screws was rusted beyond help. The other three are in very good condition.

In an effort to get the rusty screw out, I ended up breaking the corner off the magneto cap. A couple tabs also broke off the bottom of the cap.

It's a bit of a mess inside the magneto, not unlike the one I just got done working on for the John Deere BN.

Yep, those points are just as green and growing as the ones in the John Deere.

Once I got the points filed and cleaned, the gap was about where it should be, 15 thousandths (.015).

I used super glue to patch up the broken cap. I can already hear people say, "why not just buy a new cap?" Let's just chalk it up to me liking the challenge, and being cheap (not necessarily in that order). I also found a replacement screw for the rusty one. I have several spare magnetos on the shelf for just such times.

The spark plug has at some point in its storied past had its porcelain end broken off so there is a bare electrode poking out the top of the plug base

I wondered if the spark plug would still work in this condition so after confirming the magneto gave off a good spark, I checked the oil, and found there wasn't any, so I filled the crankcase. I then squirted some gas down the carburetor and gave the pulley a spin.

It's alive! It only ran for a second or two from the squirt of fuel into the carb but it was enough to show this thing is still viable. I obviously need to get a new spark plug, but I also need to find a gas tank and probably clean out the carburetor but the hard part is done. This engine was the worse of the two I bought, so I might just leave the other engine for another day.

It's a couple of days later and I decided to take a look inside the carb. It was gunked up but fairly easy to clean out since it's so simple. The float looks nearly new.

There is one small problem in the carburetor. When I was putting it all back together, I put the float and needle back in place and couldn't figure out how it was held down. It seemed like something was missing. Well, later in the evening I found a short manual on the particular Stromberg carburetor on this engine. In the parts breakdown, a flat arched spring is shown that holds the float's hinge pin in place. My carburetor is missing that spring. It's number 35 and circled in the image below.

I cut a piece of thin sheet metal to make a substitute for the flat spring, then bent it to a shape that should work ok.

The next project to tackle was the governor rod to the carburetor. Fortunately the threaded piece on the right was still on the carburetor. It threads into a small swivel block on carburetor throttle shaft. If I didn't have that threaded piece, I would have either had to try and find a bitty little die of the correct thread pitch to thread a piece of wire or buy a replacement rod. The piece on the left is some welding wire I'll use to make the remainder of the rod.

Below shows the two parts ground down in preparation for brazing. I could have welded it but there's less heat involved with brazing and less of a chance to mess up the stub of threads.

This next photo shows the finished product. I made a slight groove in the left end of the rod using a pair of wire cutters so I could put a hairpin clip on it to at least give the appearance of being secure.

The governor rod and spring are installed here. I found a spring in the spring bin that seems to be about the right size (the blue thing in the left of the photo).

With it all back together, I slipped a piece of rubber hose over the fuel inlet fitting so I could squirt gas into the carburetor. The hose was sort of a reserve to hold a bit of gas. I got the engine started and it ran quite well. I'd occasionally fill the rubber tube with more gas and I ran the engine for about five minutes. After I let the engine run the carb out of gas, I checked the torque on the head bolts. They turned about 1/16th of a revolution. You may also see a pipe plug in the exhaust outlet, there to keep bugs, junk and moisture out during storage. I'll need to buy a muffler.

The video below shows the engine running. There's some blue smoke when the engine is revved up, but I imagine the rings would seat better if the engine is run for awhile. I am bottle-feeding the carburetor with a squirt bottle, as there isn't a gas tank.

This AB engine has six head bolts. The other engine has eight, so I know it's not another AB. I'm guessing it's an AKN, which would give it six horsepower (ooooohh). The AKN was made from 1949 to 1955, making it almost as old as this AB.

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It's now a week after I picked up the two above engines. The thought of buying only the two engines from the guy was gnawing at me. I took his best two engines (in my opinion) and left the rest for him to deal with. So I called him up and asked if I could swing by and get the rest. He said sure. Great...

Yeah, to most folks the photo below looks like a dump run in the making. Not me, as I actually paid him for the opportunity to take this stuff off his hands. When I first showed  up, he said, "So, ten dollars?" I said no and gave him twenty. 

The engine in the front left is a Wisconsin AEN (it still has its ID tag), and this engine is probably the most valuable one in the mix. According to the net, it's got 8.2hp at 3600 RPM and was made from 1949 to 1957. Behind it is a Briggs and Stratton that looks strikingly similar to a B&S Model 23 I already have (link here), although this one doesn't have the horizontal ribs on the fan shroud.

This B&S engine (below) is electric start, and the starter is also a generator. Cub Cadet and other manufacturers used this type of starter/generator a lot in the 1960s on their garden tractor engines. Funny thing, I can't find any photos online of a fan shroud of this type that is smooth like this one and doesn't have horizontal ribs on it. The link above for my Model 23 shows a fan shroud with the ribs.

Along with the four engines, I was also given a box of "stuff". I like stuff. Several magnetos, several carburetors, and a bunch of stuff I still have to go through to see what kind of treasures I've just picked up.

The other two engine I got are hardly worth mentioning. One is a Wisconsin Robin off a pressure washer that needs some electronic gizmo, and the other is a Kawasaki off a generator.