| Diagnostic Resources |
Occasionally simple fixes will correct what may seem to be complex or expensive problems. Always check the simple things first and possibly avoid expending time and money. Obviously selling carburetors, generators, starters and rebuild kits is good for our business, but not if it does not fix your problem!
Before replacing the carburetor, check the fuel line, sediment bowl and tank outlet. With old tractors these often become clogged with rust sediment and cause the engine to run as if the float and float valve are damaged. The symptoms are usually, the tractor will run fine when started but begin to starve out and miss after awhile. It is also easy to associate this condition with warming up ("it runs fine till it warms up").
When the tractor warms up it unceremoniously dies with no spark. The spark does not come back till the tractor cools down. This is commonly a bad condenser. Since testing condensers appears to be a lost art, it is simplest to replace them.
The starter just won't crank over your 6-volt tractor. Before replacing the starter, check for warmth at the connections of your battery cables. Your cables may be too high of gage (the wire is too small) and your connections may be less than perfect. Remember that 6-volt systems draw more amperage and the connections and wiring and connections should be near perfect for the starter to function as it was intended.
You have spark at the right time and gas is getting on the plugs, but the tractor won't start. If the tractor has been sitting for some time, it is likely that your gas has gone bad. Drain and replace the gas with new.
If you have trouble with your tractor during high-moisture times, such as during a thaw, check under the distributor cap for moisture. Dry it all out inside and you will be on your way again.
Your tractor is overheating. Before you replace your water pump, thermostat, and radiator cap, be sure that you have the correct width and profile v-belt for your cooling fan and be certain it is tensioned properly. This can also cause the charging system to appear to be bad.
Your tractor boils out your radiator fluid whenever it warms up. Before replacing the thermostat, be sure your radiator cap is rated correctly for your system and that its spring and seal are still in good shape. The cap may be "letting off steam" under what was supposed to be normal pressure.
You have good compression on all cylinders indicating that your valves, pistons, and rings are in good shape but you have traces of oil smoke coming out the exhaust. This can be caused by your oil-bath air filter. Be sure that you are running the correct weight of oil. If the oil is too light, it will be drawn into the engine. Don't go overboard the other way, if the oil is too heavy, it won't clean the air.