Cub motor

Tue Jan 15, 2013 1:20 pm

I have a 57 cub in need of a in fame rebuild. There is a guy that want to trade a cub in on a tractor that i have for sale. He does not no what year it is, just that it is red. He is going to send me the ser. #. I no there was a hp change in the yellow cub. My question is, will all red cubs motor be the same as my 57, or which ones will work?

Re: Cub motor

Tue Jan 15, 2013 1:51 pm

I can't believe all the pros haven't jumped all over this....In general, all cub engines are interchangeable - farmall cub, offset loboy, number loboy, but there are external differences between some models that may require you to carry over parts from the old engine. For all practical purposes, the 'long block' is fully interchangeable, even with the power upgrades that came in later years.

If the red cub is round nose, you're in the same age class as what you currently have.

Re: Cub motor

Tue Jan 15, 2013 3:13 pm

Wood wrote:I have a 57 cub in need of a in fame rebuild. There is a guy that want to trade a cub in on a tractor that i have for sale. He does not no what year it is, just that it is red. He is going to send me the ser. #. I no there was a hp change in the yellow cub. My question is, will all red cubs motor be the same as my 57, or which ones will work?


Yes, and No, and All of them.

The main answer to your question is: Any cub C60 motor will bolt up to your current tractor. This also includes the C 60 power unit motor.

Wood wrote:My question is, will all red cubs motor be the same as my 57


No. Yes they will all work, but they are not the same. There were many revisions through the years. Some of the last 79' cubs were red. They had all of the upgrades.

Wood wrote:which ones will work?


They will all bolt up but as ntrenn said, "
ntrenn wrote:For all practical purposes, the 'long block' is fully interchangeable, even with the power upgrades that came in later years.
" There may be external "parts" that may be different, but WILL interchange also.

Re: Cub motor

Tue Jan 15, 2013 3:55 pm

Thanks, so now it does not mater about his ser.# if it is a good running motor, I will get it.

Re: Cub motor

Tue Jan 15, 2013 3:58 pm

Correct :big afro: Good luck

Re: Cub motor

Tue Jan 15, 2013 4:10 pm

If it is from a late, numbered series, the crank shaft is not drilled for a pilot bushing, because of a different clutch design. Ed

Re: Cub motor

Tue Jan 15, 2013 4:31 pm

But a Cub LoBoy 154 motor will interchange besides changing the front pulley, air cleaner, etc?? Or is it to "new" to have the older style crank? Reason I'm asking is because I am parting a 154 with an excellent motor, and might keep it if it will interchange with little work.

Re: Cub motor

Tue Jan 15, 2013 4:37 pm

conecting rod and rod bearings changed at engine serial number 261718. If you are thinking of swaping internal parts.

Re: Cub motor

Tue Jan 15, 2013 5:18 pm

Lots of possibilities going on. If you don't plan on taking the new engine apart, 95% of your troubles are behind you. If you are thinking about swapping parts between engines, get out your billfold, as many of the internal parts, even if they are the same part number may not swap correctly between engines. Many parts were actually select fit when the engines were originally built. For example, there were 4 sizes of pistons to match the different final bore sizes to get the correct skirt clearance. I'm sure there were other places where similar steps were taken.
On the loboy engine, I had 2 A's and 2 B's for pistons. If you know what you are doing, you can make some judgement calls on what is serviceable and still have a pretty strong running engine, if 10hp can be considered strong....

I was thinking about the questions like it was a junkyard engine transplant - just swapping the bare minimum from the old engine to the new one - such as manifolds and accessories. Once you look at the trade, you may actually think about swapping in the opposite direction - off your 'needs rebuild' to your trade in...

Re: Cub motor

Tue Jan 15, 2013 5:47 pm

My books are buried under some other stuff, so working from memory. About 1953 several significant internal engine changes were made that, in my opinion, made the newer engine considerably better.

Re: Cub motor

Tue Jan 15, 2013 5:50 pm

AL Farmall Boy wrote:But a Cub LoBoy 154 motor will interchange besides changing the front pulley, air cleaner, etc?? Or is it to "new" to have the older style crank? Reason I'm asking is because I am parting a 154 with an excellent motor, and might keep it if it will interchange with little work.

Look at the crankshaft end (rear), if you see a finger sized hole, in the end of the crankshaft, you're ok Ed.

Re: Cub motor

Tue Jan 15, 2013 11:39 pm

the later C-60 engine that was mentioned to not have the hole for the pilot bushing in the crank is from a 184 loboy. how ever it is drilled but will not take the same bushing as the older versions . It takes a thinner wall bushing. I have a 1976 std cub with a 184 engine in it. I was able to purchase the correct fitting bushing. The original engine that was in the tractor did not have domed pistons. But did have the proper camshaft. and zeneth carb. The previous owner said it had never been apart. ( original owner) The reason for the 184 engine install was the original engine died of hard water.

Re: Cub motor

Wed Jan 16, 2013 5:32 pm

Thanks for the answer to my question guys....sorry to the original poster if I had "hijacked" your thread although I believe all questions have been answered.

Re: Cub motor

Wed Jan 16, 2013 8:23 pm

I was also told that some of the 154 engines were different where the lower radiator hose came back - some were a hole thru the frame, others were open w/the hose exposed?? Have not had a chance to verify that info. Dusty B

Re: Cub motor

Wed Jan 16, 2013 11:46 pm

my engine is like that. But it is a little thicker than the older engines too