Page 1 of 1

14hp motor in model 73?

Posted: Tue Feb 08, 2011 12:21 am
by apennoyer
My 73 has seen better days. It had a rod knock when I got it in 1990, and now the carburetor is shot. I think 20 years of use is enough and would like to treat it to a new engine. At least a rebuilt one. I noticed the model 147 seemed to be on the narrow frame, same as 73. Is that really the case? (I haven't seen a 147 in person, and I know the 149 is a different frame) Can I put the engine from a 147 into the 73? I read on wikipedia that the 147 was a narrow frame and that the frame had to be notched out for the flywheel of the 14hp. I would not mind notching the frame. Thanks.

Also, is there any better way to repower a 73 or 124 more power? The best I could think of is the 147 motor, which is I guess a Kohler k321.

I grew up with the looks of the 73 and 124, and I got used to the stylish slanted grille and general good looks of those models. I never seemed to like the looks of the 149/169 models with the boxy grille and split headlight design. It may be a product of my upbringing. I started driving the 124 when I was 2 years old. (with supervision, 1st gear only, no pedals...just turn it on to go, turn it off to stop)


Thanks a lot.

Re: 14hp motor in model 73?

Posted: Tue Feb 08, 2011 7:49 am
by JimT
You will need to modify the frame for the 14hp to fit into it. The 147 frame as far as I know was the only narrow frame that came from the factory that a 14hp would fit into. The 14hp & 16hp motors are wider than the 10hp & 12hp motors (larger flywheels). Here is a photo of the notch in the frame of the 147.

Notched Frame.JPG


PS: I forgot to mention that both sides of the frame are notched.

Re: 14hp motor in model 73?

Posted: Tue Feb 08, 2011 11:32 am
by gitractorman
I think that you would be much better off getting a good 10 or 12 hp engine, and having someone who REALLY knows Kohler engines to do a performance rebuild. I know a local guy who tractor pulls with Wheel Horse tractors, running the same K series Kohler engines, but he has dyno'd a couple of his and found that he has upwards of 30hp on several of them. Now, they modify the governors, burn alcohol, etc., but what I'm getting at is the K-series engine is an excellent building block, and someone who really knows can definitely get you SEVERAL more horsepower out of a 12-hp block. Then you would have a tractor that looks perferctly original, and everything fits and bolts up as it should, kind of like a street sleeper drag car.

Just my thoughts.
Bill

Re: 14hp motor in model 73?

Posted: Wed Feb 09, 2011 12:04 pm
by apennoyer
I like that idea. My next thought is to do it with the 14hp engine as a base. It makes me wonder what the added displacement would add in a souped up motor. Also, are we supposed to retard the timing (or add octane) to compensate for the bad watered down gasoline we have these days? The retarded timing would reduce power, so maybe we would have to add power just to get it up to the stock rating.

What would it cost to rebuild a 12 or 14 horsepower k301 or k321 with a few extra horsepower? For that matter what does a regular rebuild cost? I have seen the cost of new engines around $1300 and more, so the rebuild sounds pretty appealing, especially if it can be done with better parts and more power.


I saw one guy on one of the forums used a forged crank from a 18 hp k361, which is a Kohler stock part but forged aluminium. So what if the forged rod cost $100.00. For a motor that lasts 40 years between rebuilds, that is only 5 cents per week. We could find that much in pennies on the ground on the way to the car. I don't know of many worthwhile improvements you can fund with just found pennies, but a forged con rod sounds good.

He also used a special exhaust valve, I cant remember the name. And a type d Kohler Mahle piston. All those things sound good to me.

Maybe someone could direct me to a place who could price such a rebuild.


Slightly off topic...

We used to get good gas, 100 octane leaded and so forth. Now we can't even get 100% gas of any kind. They always water it down with 10% ethanol. That is no good. I heard that Kohler sends people parts for free so that they can retard timing on some of their motors (like the command v twin aluminum motors that blow head gaskets with the bad gas and the stock timing) They send these parts for free even on motors that are out of warranty. That is amazing.

Re: 14hp motor in model 73?

Posted: Wed Feb 09, 2011 1:21 pm
by Eugene
I usually rebuild one engine a winter. Wasn't a Kohler this winter. The single cylinder Kohlers usually costs me around $100- in parts for a rebuild. That is for gasket set, exhaust valve, rings, tune up kit and miscellaneous parts. Boring cylinder and new piston - extra.

Just my opinion. I do not hop up an engine, just return it to as close to the manufacturers specs as possible. The machine is going to work, cut grass, not spin the tires.

Re: 14hp motor in model 73?

Posted: Wed Feb 09, 2011 8:46 pm
by RWRinaldi
A 10 or 12 HP K series (With the right oil pan) will bolt right up to the 73 frame. I wouldn't hack up a perfectly good frame.

Re: 14hp motor in model 73?

Posted: Wed Feb 09, 2011 8:46 pm
by junkman1946
You want to find out how to hop up your K-Series motor? Go Here:http://gardentractorpullingtips.com/index.htm He will tell you just about anything you would want to know about "soupin'-up"a Cub Cadet or a Kohler motor.He s a good guy to deal with also.

Re: 14hp motor in model 73?

Posted: Wed Feb 09, 2011 8:47 pm
by junkman1946
You want to find out how to hop up your K-Series motor? Go Here:http://gardentractorpullingtips.com/index.htm He will tell you just about anything you would want to know about "soupin'-up"a Cub Cadet or a Kohler motor.He s a good guy to deal with also.

Re: 14hp motor in model 73?

Posted: Thu Feb 10, 2011 11:06 am
by BigBill
I also have a cub cadet 70 with a replacement kohler 8hp engine too. Its my work horse on my property too. It hauls firewood all summer and winter plus i use the dozer/snow blade too. Its great on gas too. Power wise its fine too. I did put larger tires on it and its in the photohost section here just search 70 cub cadet the pics should come up.

If we change the flywheel, front bearing plate, oil pan (if needed) and sheetmetal from a 12hp kohler to a 14hp kohler engine block it will bolt up and in right? Then the 14hp will bolt right into the narrow frame with no special fitting.

I have a 14hp engine from a JD tractor sitting here and i have the correct parts to change it over to an IH cub cadet engine. I been hoping to install it in my 108 or my 1200 someday. It has the internal alternator and geared starter. I also purchased the 148 decals from ebay too. Now i do notice when i use the 12hp machines i do burn a tad more gas over the 8hp/10hp machines. If the cost of fuel is hitting $5 a gallon soon that may factor in to doing engine changes or not. Right now its got me rethinking my wants. It depends on how much i use this machine for work.

Re: 14hp motor in model 73?

Posted: Thu Feb 10, 2011 2:13 pm
by 56cub
I have a CC 147 and it has the 14 hp motor in it. To me it does seem to burn a good bit of gas. It's not horrible but it seems to use more faster than my other garden tractors that I own.

Re: 14hp motor in model 73?

Posted: Thu Feb 10, 2011 8:30 pm
by Merk
by apennoyer
Also, are we supposed to retard the timing (or add octane) to compensate for the bad watered down gasoline we have these days? The retarded timing would reduce power, so maybe we would have to add power just to get it up to the stock rating.

Slightly off topic...

We used to get good gas, 100 octane leaded and so forth. Now we can't even get 100% gas of any kind. They always water it down with 10% ethanol. That is no good. I heard that Kohler sends people parts for free so that they can retard timing on some of their motors (like the command v twin aluminum motors that blow head gaskets with the bad gas and the stock timing) They send these parts for free even on motors that are out of warranty. That is amazing.


There is no need to retard the timing on a daily use Kohler. There is no need to use 100 octane leaded gas in a Kohler motor. First thing you need to do is look at a Kohler Service manual. Page 1.5 of a Kohler Sevice manual states what octane gas and how much ethanol your Kohler can use. The old K series are flat head motor has a 6-7 to 1 compression ratio. You can use 87 octane in motors up to 9-9.25 to 1 motors. The lead can and will leave deposits. I notice the higher the octane the poorer the performace will be on a stock to mildly modified Kohler motor. I have better performace using gas with 10% ethanol in it.

Poor fuel storage habits will cause problems too. Buy enough gas to last only 30 days. Add a fuel stablizer to your gas container before you fill it. Two good fuel stablizers are Sta-Bil and the one made by Briggs and Stratton. If your gas is over 30 days old add it to your auto and buy fresh gas. Store your fuel in a cool drive place in a sealable container.

saw one guy on one of the forums used a forged crank from a 18 hp k361, which is a Kohler stock part but forged aluminium. So what if the forged rod cost $100.00. For a motor that lasts 40 years between rebuilds, that is only 5 cents per week. We could find that much in pennies on the ground on the way to the car. I don't know of many worthwhile improvements you can fund with just found pennies, but a forged con rod sounds good.

He also used a special exhaust valve, I cant remember the name. And a type d Kohler Mahle piston. All those things sound good to me.

Maybe someone could direct me to a place who could price such a rebuild.


Kohler did not made a forged aluminium crank for any of their motors. They did make a forged aluminium connecting rod.

First question that needs ask what are you going to use the 73 for?
I would consider a different model besides a 73 if you want a hot rod/playtoy. A 73 is a low production model. They are worth money in stock form.

Keep in mind horse power cost big money... You modify the motor you will need to modify the clutch, driveshaft and transmission.