Series 3000 Command 20 Overheating

[GTSRider]

Hi... just picked up a used 400 hours Cub Cadet series 3000 with the
Command 20 engine. Engine bay runs so hot that previous to my ownership...
battery box panel melted.
This tractor runs so hot I could not touch hood today to open it.
Engine runs irratic and will not idle well after running for a few hours.
I have 3 acres and a big hill it must climb.... engine gets extremely hot.
What can I do to cool it down ? .... oil cooler with fan ?
Got so hot today dipstick feel apart in tube... had to drill it to remove it.
Have never seen such a heat issue before on a garden tractor.
All the obvious has been down extreme 4 hour cleaning by me to get engine bay squeeky clean with maximum air flow.
Any suggestions welcome.... other than sell tractor.
Thanks.
Pete

 

[rcbe]

did you pull engine shroud sheet metal to clean fins?

 

[GTSRider]

No ... that is one thing I did not do....
Engine and tractor were beyond belief dirty when I got it....
so I guess you hit on problem....
I did not do it because I was afraid of difficulty.... how difficult is it ?
I since posted problem , have found an oil cooler kit for these engines...
anyone on this site have one installed ?

 

[JTKub]

There's only a few things that are going to make and air cooled small engine run hot 1) Like said, you need to clean the flywheel intake screen and you need to verify air can blow across the cylinder heads (areas behind the shrouding is clear). 2) A vacuum leak or carburetor issue where the fuel/air ratio is running lean. Generally the thing would be running poorly if that was the case. An oil cooler isn't going to help you if the engine isn't getting the airflow it needs from the flywheel fan.

Joel

 

[Transit]

You definitely need to get into the cooling fins in detail and if that means removing all the baffles so be it. Take photos to help you remember how to get things back to gather.

 

[EuropaChris]

I've got a 2544 with the same 20hp engine, and mine is an '05 with the full steel hood and side panels.

It certainly doesn't run "cool", but I have no problem with being able to open the hood, etc. after an hour of mowing hard. I clean off the mower after every use with my air compressor, and take particular attention with blowing off the screens and blower intake as well as blowing around the cylinder heads to dislodge any grass. I'm rapidly approaching 200 hours, so I probably should pull the shrouding once and have a look-see.

I do like the design of the "pre-plastic" 2500 series because all the intake paths to the blower screen have additional screening - the panel below the dash is screen as well as both side panels having a screen. This keeps a large amount of junk out of the engine to begin with. The blower screen on the Command is pretty coarse mesh compared to the fine perforated metal screens I'm used to on older engines (Kohler K series, old Briggs, etc.)

I also believe the Commands are going to run hotter to begin with due to the lean nature of the mixture. An old K series will burn twice the fuel per acre, and a lot of that extra gas cools the engine. The Command has the advantage of aluminum heads and OHV, which allows it to dissipate that heat much better than an iron flathead, but unfortunately aluminum doesn't tolerate overheating well, loosing half it's strength at 400F.

Aircraft piston engines allow the pilot to adjust the mixture "on-the-fly" and for takeoff and full power operation at low altitude, "full rich" is used. The extra fuel is used to cool the engine as well as give maximum resistance to detonation. It also gives spectacular fuel flows - 25 to 28 gallons per hour is typical on a 300 hp engine. However, once set up in cruise, you can pull back the mixture and on some engines with matched flow fuel injectors and CHT and EGT monitors on each cylinder, you can run LEAN of peak mixture at settings less than 75% power and get fuel flows of 11 to 13 gal/hour. Still sounds like a lot, but you are typically zipping along at 200+ mph, too, in a larger 4 to 6 seat plane (like a Bonanza), so pretty decent "gas mileage". And by running lean of peak, you actually run cooler and with less peak cylinder pressures than by running at best power mixture settings which is typically slightly rich of peak, as well as much lower fuel flow.

Sorry for the OT sidebar - it's interesting stuff, tho.

Chris

 

[GTSRider]

Hi.... did remove shrouding, and cleaned fins.... lots of crap in there...engine has 405 hours on it.... and I am sure it was it's first cleaning.
Because this tractor is new to me... I must ask if this engine has rough
carburation from the factory... or is my carb dirty ?
runs fine at full throttle ... but not so good at idle and low mid range.
When I cleaned fins I notice label on new oil filter just installed was burned right off filter... also as I said the battery panel is so melted from PO , that it will not stay on.... so this engine had heat issues before me, and maybe why I got it so cheap.
I would think a syn blend oil might be good for these engines as the run hot.
Pete

 

[rcbe]

certainly wouldn't hurt to drop the carb and give it a good cleanig with carb cleaner, a small dia copper wire to probe all orifices/jets, compressed air to blow any loose crap out clean, new carb kit with new gaskets. Might also be a good time to replace fuel lines, fuel filter, etc. Make sure you replace fuel filter with Kohler OEM filter for that particular engine - Kohler engines sre picky about such. No aftermarket cheapies.
Yeah, syn oil should work for that engine - but, best to go to kohler's website - d/l an owners manual for that engine (free) - chk their oil options.
and do a THOROUGH inspection of the engine being clean under those cooling shrouds - that's gotta be right or you will soon be grabbing for yer purse to repower...

 

[JTKub]

.. I must ask if this engine has rough
carburation from the factory... or is my carb dirty ?
runs fine at full throttle ... but not so good at idle and low mid range.

Pete, I know the Command 20 on my 2005 model year always idled kind of crappy. Kind of old Harley style; ratta-tatta-tatta. The throttle control was such that there was very little mid-range, and you went from idle to full blast. In the years I owned it, I just ran it at full throttle so I never had the need to mess with it. It was always smooth as butta at max RPM. Make sure you get a good look at your flywheel fan to make sure there's not a nest or something wrapped around the inside.

Joel

 

[GTSRider]

Thanks Guys.... will keep you posted on progress.
Yes ...I figured about the fuel filter... I think it must have a certain capacity for fuel and I think the small ones ... like the one mine has on there, can starve engine for fuel... making it run even hotter.
And yes... mine idles like a Harley potato potato potato.....

 

[CubUser]

The only time I had trouble with an air-cooled engine overheating it was because the timing was off - this would also affect the idle quality.

 

[turnerbend]

The only time I had trouble with an air-cooled engine overheating it was because the timing was off - this would also affect the idle quality.

That's the same thing I was thinking.

 

[GTSRider]

Ok... but in this case.. I'm not sure....
have cleaned today all fins... air intakes... **** engine is squeaky clean....
will have to try next time I have to mow this week and see what happens...
I have a big hill.. about half an acre... and about 2 acres of flat...
but the hill stress out every tractor I have ever had.... but this one is ridiculous.
Melting of plastic and no way the other day could I touch hood..it was just that hot.
I also get a lot of heat on me the operator... that can not be normal either,
so I am taking the tip from someone on here , and installing a good quality
6" fan at front base of engine just below front pully to draw engine bay heat out.
Pete

 

[CubUser]

I have a big hill.. about half an acre... and about 2 acres of flat... but the hill stress out every tractor I have ever had.

Two bits of advice... 1) mow the hill side-to-side, not up-and-down or if you can't do side-to-side safely try going at it at a diagonal angle -and- 2) over-inflate the tires by at least 5psi - this alone will do 2 things for you, a) give you better traction because you'll have more weight distributed on a smaller contact patch & b) will decrease the rolling resistance thus making it easier on the transmission and ultimately the engine to move the tractor along whether going uphill or over dead flat terrain.

 

[GTSRider]

Hmmm good point...but tonight I was thinking of running without side panels ?
What say you ?

 

[turnerbend]

Two bits of advice... 1) mow the hill side-to-side, not up-and-down or if you can't do side-to-side safely try going at it at a diagonal angle -and- 2) over-inflate the tires by at least 5psi - this alone will do 2 things for you, a) give you better traction because you'll have more weight distributed on a smaller contact patch & b) will decrease the rolling resistance thus making it easier on the transmission and ultimately the engine to move the tractor along whether going uphill or over dead flat terrain.

I disagree with over inflating tires for better traction. The more rubber on the ground the better the traction.

 

[GTSRider]

What is the concensus of running the 3000 series WITHOUT side panels ?

 

[recon701]

I wouldn't run it without the sidepanels, because it'd be a lot easier to get dirt and clippings all over inside the engine bay

 

[micman32]

I have a Command 20 in my 2518. It has close to 500 hours on it. I usually mow for 2 to 3 hours at a time. I have never had heat related issues.
I would never run her without the side panels. They keep alot of the clippings out of the engine bay. Whenever I clean the deck, I blow out the screen and the fins on the engine.

Michael

 

[flyhal]

I have a Command 20 in my 2518. It has close to 500 hours on it. I usually mow for 2 to 3 hours at a time. I have never had heat related issues.
I would never run her without the side panels. They keep alot of the clippings out of the engine bay. Whenever I clean the deck, I blow out the screen and the fins on the engine.

Michael

flyhal here- I have own Cub Cadets since 1979 in one form or the other. Other than my 2185, there was ductwork clear out to the grill to channel the hot air out from under the hood. This 2185 that I recently purchase runs very hot. When you lift the hood, there is a rush of hot air coming upwards. Reports are that the plastic light system melts and many of these later models are running without the light installed. I have had no heating problem with the 17 HP 682 model so have fashioned some tin to channel the air out to the grill. I think that this will solve the hot air problem. Also, with this Kohler Command engine, one might want to idle the engine down for a least a minute to let some of the hot air blow out from under the hood. Engines always get hotter when shutting OFF. And this is when the plastic could melt, or burn the paint off the hood. I am surprised that the air flow was not ducted OUT like the earlier models, especially when running lean like these engines are designed to perform. The only thing I don't like now is the location of the muffler versus the PTO pulley and rubber belt. Rather HOT for the belt. I put on a new belt and see rubber tracks above on the hood which indicates shedding of the new belt. The old systems had the muffler above the PTO. Design took over with the new sloped hoods which has created this whole problem of heat