hand crank pin?

In place of the pin on the shaft where the hand crank attaches on my '44 H, I have a nail added by the previous owner. Well, the nail just doesn't look right for a proper restoration.

What sort of pin should be in there?

Mike, it is a standard, hardened steel pin. You can find rod stock at hardware stores, home depot, Lowes, etc. You will need to cut it to length and dress the ends. I am not near my tractors right now, but you can also determine the diameter of the rod. I would think that you want it to extend at least 3/8" to 1/2" out of each side. Also, if you can only buy cold roll, you can temper it by heating to just cherry and quenching in oil. Don't quench in water as it will be too brittle. Also, you want to heat it until it barely starts to glow. If you take it to full cherry, once again it will be too brittle.

IMHO.

My 400s have a roll pin in them. You can buy them at the hardware store. Measure the diameter of your hand crank. That is the length that you need to buy. Measure the diameter of the pin that is in shaft. Or measure the slot width in the hand crank. Should be 3/8 by 1 1/2.
SDE

MikeCA: Cut the head and threads off a #8 bolt, cut to the proper length, and drive it in the crank.

At the machine shop where I worked we ordered dowell pins for such stuff. They"re hardened and solid. Try an industrial supply or catalog.

Dowel pin sounds like the easy, and best looking fix. I'll hunt that down.

Thanks all!

IMHO here...but a roll-pin is probably best practice because the spring steel will conform to a hole slightly out of dimension. The spring tension will also "grip" the hole without having to carefully engineer an interference fit.

Relative to quenching and tempering cold rolled all my information and experience says you are simply wasting heating fuel doing that. You might come closer to hot-rolled but at no time will the yield strength improve without a surface treatment such as nitriding, carburizing (case-hardening) or going to a medium-carbon steel or tool-steel that will respond to heat treatment...but mild steels go red hot to supercooled with no change in the final state...just simply not enough carbon in the microstructure.

A dowel pin, while it may work is very very brittle, will likely snap if overloaded (generally hoping that doesn't happen in this application) and if broken off is generally a large pain because standard HSS drill bits won't touch it and solid carbide drills are generally a large waste of money in a hand-held drilling application.

Matt, you are correct. Cold rolled will always have the same properties, no matter how much it is heated and cooled, it will still be cold rolled steel, and hot rolled really isn't any different.

...a roll-pin is probably best practice...

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Won't a roll pin bend under the load since it is hollow?

Mike, I obtained a new one from a long time (prior to letter series introduction in 1939) IH dealership with no problem. It might have been some old stock they still had on hand but don't really know. It is part no. 576483R1 and cost next to nothing. My H had a loose fitting bolt in the hole which would slide back and forth. You will probably never crank start it anyway so regardless of what you use will be fine as it is probably an appearance item only. Hope this helps, Hal.

Actually I am converting it back to a mag so I can crank start it for demonstration purposes.

(quoted from post at 09:05:55 10/25/09)

...a roll-pin is probably best practice...

Click to expand...

Won't a roll pin bend under the load since it is hollow?

Click to expand...

It would take a very severe load to bend or break a roll pin, they are made of tempered spring steel. A roll pin or plain mild steel solid pin would be more than sufficient for what you want to do. I don't think you will be breaking either one by hand pressure on the hand crank!

Mike, if you have never hand cranked a tractor you will want to have someone show you how it's done. I don't recall what is in the owner's manual if anything as I learned how it was done 5 decades or more ago when in 4-H but the guys who owned the hand start tractors didn't want anyone else near their tractor with a crank. Never and I mean NEVER put your thrumb around the crank handle and I always started them with an up stroke only. You will learn some new words (maybe not for a Navy guy) unless your tractor is an easy starter and everything must be adjusted correctly so it starts quickly. Be careful, Hal.

Oh yeah, I plan on getting some instruction.

Just a couple of quick comments here. First off, I won't debate that cold roll won't take hardening like a higher carbon steel will, but it can be hardened to a point, and it definately can be case hardened (which is what I outlined). You can even get a better case harden by using charcoal, but that takes a bit more time. Cold roll will definately not take a temper either, so no debate there. There are a couple of ways to make cold roll harder than it comes from the store, but I do agree that it is nothing like high carbon steel.

So, I have agreed on a couple of points. Case hardening will prevent wear to the pin, and I have a couple of 'crank" start repairs to prove it......ain't no battery on my F-20.

Was trying to help Mike out with what I believed would be representative of the original pin. Roll pins will absolutely work, but for his H, they won't look original. I suggested steel rod stock that is readily available. Also, cold roll is easy to work with common tools like a hack saw, and a bench grinder.

Sounds like I am being a bit defensive, and maybe I am a bit, but I don't disagree that high carbon or tool steel will definately harden to a greater extent, and yes Virginia, cold roll steel cant be tempered. so I guess my bottom line is that Mike has not received any "bum" info here, just some that is easier to implement than others........

ps. do a search on "hardening mild steel" on the net...........