Garden Tractor Info

Keeping your garden tractor purring like a kitten can sometimes be a challenge. Repairs most times aren’t all that hard, but knowing what’s wrong can be a little harder to figure out. Here’s some common types of questions written in:

Q: Jim, I have a John Deere model 425 garden tractor that has about 800 hours on it. I use it for mowing only. When I start it up it smokes a little and it will only stay running when the choke is half way up. Can you help me?

A: I would start with the basics and replace the spark plugs, but I think you should clean out and overhaul the carburetor. Don’t worry about the smoke when you start up, as long as you are not taking any oil.

Q: I am working with a New Holland garden tractor. It has new plugs, filters, and fuel at the engine. The 24 horsepower Kohler Model CH22S engine runs O.K. for about 30 minutes until it’s warm then spits, sputters, backfires, and flames out the exhaust, all of which results in a great loss of power. Then after cooling down, it acts the same way again.

Your thoughts are appreciated.

A: Starting with the basics, do you have 5-30 oil in it? This engine has hydraulic valve lifters and they can pump up and hold the valve part way open causing a back fire. Another possibility is you might have a loose valve seat in one of the heads. It could also be a bad hydraulic valve lifter.

Q: I have a 214 John Deere lawn tractor. I put all my snow removal attachments on and everything was working fine. I parked it, came home a week later, and it wouldn’t start. I can start it if I cross over the solenoid. I’ve checked all the wires and everything seems to be fine. So what do I do next?

A: Check the wiring to your PTO safety switch or check the switch. Check the wiring to your shift lever safety switch and also the switch itself. Check the wiring condition plugging into your ignition switch or maybe it could be a bad ignition switch. If none of this takes care of it give me a call.

Cub Cadet, Simplicity, Alles Chalmers, Ariens, and John Deere have garden tractor models that have hydrostatic transmissions. If you have problems with a hydrostatic transmission normally you have to make a decision to:

a: Rebuild it. (somewhat expensive and can be done only if the parts can be found)
b: Replace it. (very expensive and only if the same or compatible transmission can be found) or
c: Get a different garden tractor.

Obviously it’s best if you prevent problems with the hydro transmission before they happen. One of the most common and preventable causes of the hydrostatic transmission failing is pulling/towing the garden tractor. Just don’t do it, not even a short distance. If we need to move a non-running garden tractor around the shop we will even skid the wheels rather than take the chance of ruining a good transmission. We specifically overhaul Sundstrand hydrostatic transmissions, there are other brands. These are a couple of e-mailed questions we have answered about Sundstrand hydrostatic transmissions. It will give you an idea of the symptoms of the hydrostatic transmission failing and a few things to check out before you overhaul or replace it.

Q: I have a question concerning a larger piece of equipment. I have an older Ford front loader with the Sundstrand hydrostatic drive. About a month ago while moving a load of horse manure the unit decided to not move anymore. I called a friend and he guessed that it could be the neutral switch just out of adjustment. Ring any bells for you guys? I don’t know anything about hydrostatic transmissions and am lost!

A: A few recommendations:

1. Check if the driveshaft isn’t stripped and slipping on the transmission.

2. Check the linkage going from your hand or foot control down to the transmission and make sure it did not unhook or fall off.

3. Also check on the arm that hooks on the shaft going into the transmission and make sure it is not slipping.

4. If you have a gear transmission behind your hydro transmission, make sure that it did not jump into neutral.

5. Then, did you check and see if you have a broken axle?

Q: I have a John Deere LX 176 lawn tractor, 38 inch mower deck, with a hydrostatic transmission. It has a few hours on it but is in good condition, with one small exception. It has slowly refused to climb the slope in my front yard. About half way up it simply gives up and makes a shuddering sound. This seems to also be aggravated by temperature. The colder it is the better it works and then as the tractor gets hotter it won’t back up even on a slight incline. I fear the hydro needs rebuilding, do you agree?

A: First check to see if your traction drive belt is not slipping or you have a locked up idler pulley.

Q: I checked both conditions as you suggested and both are to specification. It has a new John Deere belt. The condition as I described it before also gets worse as the temperature of the transmission rises. After an hour of use the speed in both forward and reverse slows with any change in grade. I have had several John Deere riding lawn mowers before and used them on the terrain with no similar results.

A: Yes, I agree, you are correct that your problem is a bad hydrostatic transmission. It looks as though there might be 3 different transmissions, so we need to start with getting the serial number from your lawn tractor.