1957 300 Utility Rebuild

I have a 300 U and its smoking bad. I think it needs new rings and it might need bored out but I have a motor out of a parts tractor that I want to rebuild so mine is not out of commission. Can anyone give me a estamate on how much it would cost to rebuild the motor?

AJ,

Without more details, the rebuild price range could go from $1000 to $2500.

But do you really need a full rebuild? Is the smoke black or gray? Gray smoke comes from burning oil and has a characteristic burned oil smell. This engine is overcarburated with a M carb. If the carb is crapped up, you may be putting way too much gasoline into the engine and getting a lot of black soot, and black dry carbon on the spark plugs. Burning oil will make the plugs black and oily, usually wet looking.

The 300 Utility had a 164 cu in engine, while the 350 had a bit bigger 169 cu inch engine. Your title to this thread made me doubt that you know exactly what you have. The 300 Us were made in 1955 & 1956, but by 1957 the 350 was the model. Before ordering any parts, you need to know exactly what engine you have. To make matters even more confusing, it is possible to swap into the 300 U an engine from the Farmall H at 152 cu inch. It is not quite a direct swap, as some of the external parts from the 300 engine need to be used like the front timing gear cover. Now you need to figure out what some previous owner may have done, or determine that you have an original setup.

The family of engines that I have described all have dry sleeves, but of different bore diameters. There were many options for pistons, some stock options, and some aftermarket high compression pistons. All this amounts to: There is very little likelyhood that you will be doing a stock rebuild. You won't know what you need until you get into it. I had a small 4 cylinder tractor engine rebuilt 2 years ago that went $1000 over my estimated price. It is much cheaper to do careful diagnostics (compression check, cylinder blowdown, etc) and then repair what is needed. But if you got the $$, I am sure that some good shop will gladly accomodate you for a full rebuild.

Any one of the engines I mentioned are mighty tough little engines, and are readily rebuilt. The head with the overhead valves probably needs to go to a cylinder head shop for valve work. I have recently spent $500 on a head rebuild.

Get your details in order, and then good luck with your decisions.

Paul in MN

The smoke is blue and 2 of the 4 plugs have black oil deposits with one completely covered to the point where the engine misses. I hope to use my parts tractor motor so I can take my time when I have the cash to do it right and not loose my tractor for weeks.

The 300 utility had a C-169, the 350 had a C-175.
D Sellers.