# Shortblocking a Tecumseh TC300



## stinkynathan (Jan 11, 2010)

First post here. I could see myself spending some time here. 

I bought an ice auger a week ago that wouldn't start. I shouldn't have bought it, but I did. It's powered by a Tecumseh TC300-3008A. It dumped all of the bearing needles where the rod connects to the crank. Took it apart, rebuilt the carb, and put all the needles back, hoping in vain that the engine would magically not throw the bearings again. It did. Cylinder and piston are scarred and I'm sure the rod is bent.

I found a brand new, cheap short block for it. It has a 5/8 by something PTO shaft and my clutch is for a 3/8"x24 shaft. When I talked to the guy about the new short block he told me that the cases are all the same and the 3008A designates the shaft size (among other things, I'm sure).

I see three options here: 
Have the 5/8" shaft milled down to 3/8"x24
get my crank checked to see if it's straight and swap it into the new case
have my clutch drilled out and tapped to 5/8" x whatever the new shaft is.
I see the first two options being the best. While there's still a good supply of these clutches I'd hate to go through a few of them each winter because the 5/8" hole weakens it too much.

I'd buy a "proper" short block, but the TC300-3008A short block is $220 and I can get this one with the "wrong" crank for just over a quarter of that cost.

Any ideas?


----------



## 30yearTech (Sep 14, 2006)

Crankshafts are cast and pretty hard to damage (although not impossible). Take a *good* look at your crankshaft and if it looks alright, you would probably be good just switching out crankshafts on the short block with your old one.


----------



## geogrubb (Jul 28, 2006)

I think I found a 2-cycle engine for the ige auger. Have a good one. Geo


----------



## stinkynathan (Jan 11, 2010)

Am I correct in assuming that the connecting rod is the weak point here? My old crank looks good to my eyes. The bearing surfaces are good and it spins in both crank bearings smoothly. What would I need to do to truly know if it's safe to throw in that new short block?


----------



## 30yearTech (Sep 14, 2006)

If there is no apparent damage to the bearing journals on the crankshaft, it should be alright to reuse.


----------



## 30yearTech (Sep 14, 2006)

geogrubb said:


> I think I found a 2-cycle engine for the ige auger. Have a good one. Geo
> 
> http://www.youtube.com/watch?v=jXHvY-zY9hA



That's a pretty interesting video. You should be able to drill through the polar ice caps with that!


----------



## stinkynathan (Jan 11, 2010)

Finally got around to ordering the short block today. I guess we'll see how this goes....


----------



## stinkynathan (Jan 11, 2010)

Got it put together today, but managed to muck up the fuel pickup in the reassembly. Should be an easy fix.

The governor vane broke at the pivot as I was putting things together and they're not available any more according to partstree. Hopefully I'll get lucky and my local shop will have one, but I'm not holding much hope. How bad will it be if I rig up a way to bypass the governor, accepting that I'll need to be careful with it on the ice?


----------



## 30yearTech (Sep 14, 2006)

Just need to be careful not to over speed the engine for any length of time.


----------

