Model A rebuild

Traildust

New User
I have a 1944 model A that I have a apart to replace the crankshaft due to the splines on the clutch end being damaged. While I'm this far into it I considered doing a bit to raise the HP some. It has .45 oversize cast pistons in it and later rods with insert bearings whereas factory would have been the babbitt style for this year I think. Correct me if I'm wrong. Assuming these could be late A (gas) rods are they any different than the earlier ones compression wise? The head is an all fuel one by the casting number. I plan to have the cam reground for sure before it goes back in but what else should I consider doing to this to bump up the HP? I'm not looking for any crazy HP numbers like some of the pullers out there just the best bang for the buck with out spending several thousand dollars.
 
Well, probably the best thing would be to replace your pistons with high compression aluminum ones, they ain't cheap, but chances are your cast ones were just factory low compression factory type replacements for when the tractor was overhauled many moons ago.....That was the usual procedure back in the 1940's and early 1950's. Hopefully your block isn't worn so much you might have to have it bored a little larger to,.090 in. over or .125....but if it is worn you'ld want to bore it and then fit pistons to that size
 
I've been working on a 1944 POS Model for 5 years. I'm tighter than bark on a tree.
Bought this thing VERY Cheap, & still will end up having 2K in it without good tires.
I had a lot of the parts on hand & still has become a Money pit. I didn't need the tractor
just wanted to use up what was on hand which I have. I've been from drawbar to the radiator
don't ever plan on Pulling it , but do plan on mounting a Snow plow, all I want it to do
is start & run good like my other, still not done & only tinker on it when it's much warmer
But decided every time I seen something that wasn't quite right I fixed/rebuilt it right.
You can spend a lot of dollars for just a little more power....
 
Thanks for the input. I'm sure I will have more in this tractor than its worth but I knew that when I bought it. I seem to recall a few saying they weren't happy with how the tractor ran after putting aluminum pistons in a two cylinder vs the cast ones. Perhaps it was a balance or vibration thing. Any truth to that? Is the quality on these pretty much the same or is there a better place to buy them from? I noticed today that custom or welded rods are a thing for these but are usually used with a stroked crank. Any reason the rods wouldn't work with a stock crank?
 
Your inserted rods are really from a 60 and there is no difference in length and will work fine with what you have. we have several older A's with aluminum pistons they work fine and they would raise your compression some with the alfuel head
 
Traildust You can weld the spline end of the crankshaft and grind it back to save having to buy a crankshaft. Put a dial indicator on it so it runs true. The problem running insert rods is you have to crankshaft std .010 or .020. John Deere makes a .002 but around $110 a rod. Babbit rods can be adjusted to take care of quit a bit of wear. Your .045 cast iron pistons could be all fuel of gasoline. Gasoline will be taller to make more compression. If you bore on the block is not worn lengthen the rods would be cheaper than buying new pistons. At least $450 for new aluminum ones and you could get more compression if you want it. Don't go too much and use 91 octane. Lynn
 
I grew up on a 49 A that had inserts and shims on the rods and they had never been changed out before I went into it. It was a family tractor and I know it's history.
Richard
 
I have a late model A head A4226r if i remember right. these were much higher compression than the old A heads Has new valve seats very good valves all treads are good no broken bolts will sell call 605 270 1844
 
I would be interested though shipping costs would be a concern. Whereabouts are you located Kent? I'm in Indiana.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top