Oliver Super 55 advice requested

[Tramway Guy]

Just bought an Oliver Super 55 gas that runs but needs engine work (blue smoke). Serial number makes it a 1956, has foot start and real good tin.
My question is, should it need sleeves and pistons, do I go for the 3-5/8" overbore, or go to the 3-3/4"??
I know it has the smaller carb, manifold, and probably smaller passages in the head, so maybe the huge overbore would not be a big improvement? I would like to hear of others' experiences in this regard...

 

[rrlund]

I don't have a horse in this race so it doesn't matetr a lick to me,but a tractor that small and for what you're probably going to use it for,I don't think you'll gain enough power to even notice. I've got a hunch the bigger bore will just be a little harder on the starter. Personally,I don't think I'd go with the bigger bore. Just not worth the wear and tear.

 

[Anonymous-0]

I would not consider the 3.750 set. The 3-5/8 set probably. How hard are you going to work this tractor? Blue smoke? rings, valve guides? Have you torn it down. If you are thinking rings don't order any till you have it apart as not all use the same width rings.

 

[Tramway Guy]

Thanks:

No, I haven't torn it down yet. Haven't even got it home yet. I will not order anything till I have it apart and evaluated, for sure.

I don't think too much of rings alone, unless the bores and pistons are in very good shape.
I haven't got the tractor home yet, I wanted to get others' opinions in advance.

 

[mmoore]

The 3.75 bore will make about 40 hp. They also tend to blow head gaskets under heavy load.