thrust washer

[38racing]

I have a 92 mtd snowblower. I think I got it from original owner, but not sure.Some how the moon key connecting the large wheel drive gear to the wheel axle came out. I did replace the drive wheel rubber but it's on a different axle. I did find the key on the floor. The parts manual shows a thrust washer between the gear and the chassis just to left of key. Machine has no such washer. I'm thinking that I can use any washer matching the size? It's a low speed setup.

[bgsengine]

A thrust washer has precision machined faces and thickness you won't find with a regular plain flat washer which typically is stamped out of metal, so it won't have the same polished precision thickness to it. Before bothering to try and put a washer of any kind in place I'd probably look at what the thrust washer actually does - parts manual may show a thrust washer, where they might have changed the parts machining to incorporate a thrust face on the actual installed part.

[38racing]

A thrust washer has precision machined faces and thickness you won't find with a regular plain flat washer which typically is stamped out of metal, so it won't have the same polished precision thickness to it. Before bothering to try and put a washer of any kind in place I'd probably look at what the thrust washer actually does - parts manual may show a thrust washer, where they might have changed the parts machining to incorporate a thrust face on the actual installed part.

Thanks. I'm just puzzled why a precision washer would be needed. It just separates the turning gear from the axle bushing that protrudes inside the chassis. I may pull the pan off my 92 similar unit and see if it has the washer. Would a thrust washer be a different hardness?

[38racing]

When I looked up the washer number that I thought was the one, mtd showed it as thrust washer. Now I find 2 ipls for what seem like same blower. Both ipls use reference 34 for several locations of this washer. Ipl 1 is 736-0351 flat washer .76 id x 1.5od x.03. Looking it up on mtdparts it's called a thrust washer. Ipl 2 is 736-0188 fl-wash .76 id x 1.49 and looking it up says it's a flat .washer, interestingly says x.06. Since same washer on axle outside chassis I'll measure their thickness.

[bgsengine]

Oh those, yeah those aren't really precision , but they are not your ordinary hardware store washers either - Thickness can matter, as well as O.D. and I.D. - Some of those washers, especially those by the drive gears (which are keyed to the shaft) had to be a very close fit to the shaft, otherwise they would wear and ride up on the key and allow the gears/bearings/pulleys to slip out of alignment - they were mainly in place to keep other gears from wearing into the key (or vice versa) as things moved side to side (MTD was never that great on tolerances and engineering) So as I said before, it'd be good to be sure you know and understand the purpose of the washer - whether it be for a shim (for alignment) or thrust spacer (to keep things from banging into a key or some such) or as an actual bearing surface (hardened thrust washers, which often are also polished with a hard chrome surface - thrust roller bearings can ride on them - those are precision items though) - Could be any or a combination of all those things that a "thrust washer" in MTD parlance may be used for.

[KE4AVB]

Thanks for the size specs. My system didn't have those specs listed. MTD price files always seems to missing that info.

I might need along those specs and having it on hand helps.

I do tend to use harden washers here when I can find them but there are time you want a softer washer to wear instead of what it is protecting.