Allis Chalmers B "Stiff" engine

[BingHawk]

I have a 1938 Allis Chalmers B with a hand crank start only.

A little back ground, It was my grandfather's and while I have never seen it run, I recall my father saying that they could only get started by tow starting it.

After sitting a long time in the barn (30+ years) the engine was stuck solid. I removed the cylinder head to free up a stuck piston. I cleaned up the head and valves. Then checked and adjusted the rod bearing clearance (applying some engine assembly lube in the process).

But the engine still seems "stiff". I can move it by hand spinning the cooling fan. But it seems to take more effort than I would expect.
When I try to use the hand crank I certainly can't get what I would consider to be any reasonable momentum behind the spin. It's really stiff and often "pushes" the hand crank back out.

To be clear I am not talking about it almost starting and the momentum pushing the hand crank back out. What I mean is the resistance is so much that when applying torque to the hand crank, instead of rotating the engine, the hand crank pushes itself out. (I have started to wear shiny spots into the crank pulley as a result of this).

I had hoped that when I tried to tow start it, it would get the oil circulating and lubricate things and make it better. Sadly my timing was off so I couldn't get it started, but the engine did seem to turn over just fine. But still, the engine behaves the same.

I would appreciate any thoughts on why the engine might still be so stiff.

 

[Butch(OH)]

Mark the spark plugs wires 1- 4 or take a
pic so you know where they all go. Then
remove all the plugs and try cranking it.
You should able to easily turn the engine
over with one arm. If not you have tight
bearings or tight pistons or rings. If that checks out and as long as there is not fluids in any
cylinder any cranking resistance withvthe
plugs in is normal. Even with the plugs in a person
with normal arm strength can pullna B
over center with one arm.

 

[Mike(NEOhio)]

Are the pins on the crank worn or the hooks on the pulley jaw? Applying more torque should seat the pins tighter in the jaw.

 

[DrAllis]

A mechanically proper engine will kick-back on any compression stroke. I don't mean ignition kick-back, but from trying to compress air.

 

[Dick L]

If you can turn the engine over with the fan the engine is not stiff. I would guess the crank pully has the ends that catch the pins on the hand crank are gone. I have a half dozen or more pullies out in the shed like that. I have on one pully that I wanted to use a hand crank on used a burr on a 1/4" drill to hollow it out to catch the pins. A rat tail file would work if you wanted to do it by hand. When the pully correct you do not have to put inward pressure. If it kicks while pressing in on the crank your in for some pain. I always pull up on the crank while pulling out on the crank on the B's and C's where there is no spring as some tractors have. I used to be a bull with heavy work and about as brave but I have never been brave enough to spin a crank when starting a tractor. 1/4 turn at a time pulling up is all it takes if it is ready to start. Even it takes 50 pulls I aint spinning it.

 

[BingHawk]

Thanks everyone for the ideas.
I was able to get it tow started this past weekend. Took a few tries and some starting fluid but runs pretty good. No smoking or knocks and doesn't sound like it's missing.

Also after running a bit I think oil has gotten into some places that haven't seen oil in 30+ years so it does seem to rotate a bit easier now.

Still, upon closer inspection the crankshaft pulley doesn't look "great". I'll try and find a decent used one, or try the rat tail file trick suggested.

Thanks again and Ill update when I get a chance to dive back into it.