1966 cub cadet 123 motor rebuild

[over my head]

This summer I purchased a 1966 cub cadet model 123 for $350. Did some work on it this fall getting it ready for winter. On the first big snow I blew the motor. My fault, the oil was low and it ran down faster than I thought it would. Yes I had checked it several times but this was the first time I was putting the tractor to real work since getting it. The rod didn't go through the engine so I am considering rebuilding it. It still turns.
My first question is do you think it is a good idea to attempt this? I have some mechanical ability and am interested in the project. I have already started but could be convinced to use a mechanic if that would be the right thing to do.
Second question would be should I just repower? It is more expensive and my fear is that I will get a less well made engine that will not be as good as what I have. I have looked a Kohler and B&S as possible sources for new engines. Price seems to be in the $1500-1800 range.
Also is this model considered a narrrow frame?

 

[over my head]

never mind, motor is cracked behind the starter. Going to need a new one. Any advise on a good engine to repower with?

 

[highboy1975]

the cheapest thing to do would be to find a similar donor and just run it. otherwise, theres a few websites that discuss repowering in pretty good depth

 

[Gator6x4]

Purchase another mower and sell the parts from the one you have now. If memory serves the Cub 123 had a Kohler K301 engine. You will think you have purchased shares in a gold mine when buying a replacement Kohler K301 cast iron engine.

 

[over my head]

Checked out prices and it seems that I would have to repower with something else as the K301 is no longer made. Found a guy on ebay that had one remanufactured for pulling. He wanted @ $650. Then someone in email suggested a vangurd 18 hp but didn't say the make.

 

[over my head]

would a K321 work as a replacement? It's a 14 hp. Aside from the dipstick being moved it looks almost identical

 

[7254t]

I have a friend that has a brand new k321 never ran complete with starter he wants 1200.00 or best offer.

 

[dex3361]

I have a friend that has a brand new k321 never ran complete with starter he wants 1200.00 or best offer.

I repowered my 129 Cub Cadet with a 16 HP kohler Kseries but it has to have been configured for a Cub they have a different oil pan and I think the PTO shaft is different. Where are you located?

 

[over my head]

I am in vermont. A few places on the net have engine blocks for sale, would need a lot of parts off my current one.
Will

 

[Donsyl]

Over my head....be careful when selecting a different Kohler engine.....some of them are not made to fit in the narrow frame....

 

[dex3361]

How about one of these Small Engine Warehouse: K301-47504 -

 

[highboy1975]

holy smokes. im not sure, but i would think hed be better off finding a donor and having it rebuilt.

 

[moe1942]

overmyhead. Where are you located. I may have your solution if you are close enough.

 

[over my head]

Where did you find that kohler?? I looked all over that web page and found nothing. It says that they don't have any in stock, does that seem to imply this is a rebuilt one or a knock off? Does anyone know how long ago they stopped making these? I thought it was a long time ago.

I am located in Vermont, Ludlow to be precise. I bought this tractor to move snow around the driveway. Not as the primary plower but to clean up after the plow. I bought it for $350 this summer. It took a while but I had it running really well, or at least I thought....

I hadn't really put it to use until the first storm and I had always checked the oil. First day using it to plow I checked the oil and it was exactly where it had been. So the next I skipped that. Big mistake I guess. I noe know that the first thing that I should have done when I got it home was to do an oil change. I have never really been into small engines before and most that I have are new so these issues are less frequent. There is a cub over in NH with a front loader on it it is a very similar machine. I have been thinking about purchasing that and then using mine for parts.

 

[over my head]

while I have been looking into what to do I decided to learn a few things from all this. The first lesson I already learned, check the oil!!!! I have started tearing down the motor. I have never seen the inside of a motor before so I thought since I have nothing to loose.....

When I got the head off the top of the piston had a bit of oily residue on it but the area around the piston and the lifters was really full of carbon deposites. Is this normal for an engine this old or does this show that something was going wrong before I bought it. I have kept everything that I have removed so far, although since I wasn't thinking I would need to put it back together I haven't recorded every nut and bolt I have removed.

On the back of the engine there are a few parts that connect to the drive shaft. I removed the one that had the slot in it to recieve the pin in the end of the shaft. There is a nut inside that holds on the part that part was connected to. I think I will need some of these parts no matter what I do but I can't get the nut off because the engine turns with it. Any ideas? I have the manual for the K301 in .pdf form but it doesn't cover this as it really isn't part of the motor. I also can't get off the front pto. And I don't know how to.
Will

 

[over my head]

Another question, does anyone know what model #s have the narrow frame? Since I want to plow with whatever I get, and I already have the plow for the 123 I would need another narrow frame.

Thanks
Will

 

[dex3361]

Where did you find that kohler?? I looked all over that web page and found nothing.

I did a web search and located it. I also saw a list on wich model years have the small frame. Cub Cadet Frame size.

 

[over my head]

Thanks dex3361. I had seen that list before but never realy looked at the frame size.

What about buying a new/used block? There are 2 on ebay right now. Both are less than $10 dollars and look, on the outside, to be in about the same shape as the one I have now. How hard would it be to put my stuff on onther K301 block? I opened the bottom of my block already and took a look. There isn't too much in there. Of course what do I know? I guess the most critical part is getting the timing right so the lifters and piston work correctly. Is that very hard? Then I could get the rebuild kit for @$80 dollars and I would be off and running again for less than $100. Sounds good and I love a challenge. If I didn't I wouldn't have bought a 50 year old tractor!

 

[over my head]

well a new motor has been purchased. I got a Techumsa 11 hp coming from Small engine warehouse. Strangely enough when I first got the tractor I went to their site and saw this motor but at the time I was thinking it wasn't what I wanted. But here we are and it was well priced and has a kit to fit this model. Just hope it is a good engine......

 

[RandyT]

Be aware that tecumseh when out of business a year ago. as a dealer i was having problems getting parts 30 days after the stop of production. all parts available are limited to distributor stock and dealer shelves