I have recently purchased a 1976(ish) JD-310A Backhoe/loader. I am having issues with it overheating after about 20-30 minutes of moderate workload. I am fairly new to working on big equipment and especially Diesel Equipment. Ive tried everything I can think of so far. I Flushed coolant, replaced thermostat, changed the air filter and put a new radiator cap on. Even after all of that, the old Girl is Still overheating. Anyone out there have some advice for me? Any would be truly appreciated.
The best way to diagnose overheating is to get a non contact thermometer, aka temp gun, and take it's temperature. While it's overheating, in the red, bubbling, however you consider overheating, take the temp of the thermostat going to the radiator, the inlet on the engine coming from the radiator, and a few places on the engine. that will tell you whats moving and what's not moving fast enough. the shoot from the hip approach: clean the outside of your radiator, use an air nozzle, then a garden hose, if it's oily then use dawn dish soap and let it soak. You think it's clean? put a light on one side and look through the other side. Sometimes you'll have to do some disassembly, it's very hard to clean a radiator with an oil cooler in the way. What are the symptoms you're seeing? and does it cool down if you let it sit a few minutes at high idle?
Welcome to HEF, Newtoheavys, Fan belts tight ? Any chance they are glazed and slipping even tho they are tight ? Remove the radiator cap and look for bubbles. They would indicate a cracked head or leaking head gasket. If you can see the tops of the radiator tubes with the cap off look for solder bloom that may be chocking the coolant flow.
Two members posting at once !
Welcome to HEF Newtoheavys ! What they ^^^^ said.
And if you don't know what Delmer is talking about by a non-contact thermometer check this out: https://www.amazon.com/Infrared-The...ocphy=9005173&hvtargid=pla-349733104962&psc=1 No idea how good that one is but for the price if it only works and lets you find the problem once it's cheaper that what you spent on the coolant and thermostat already!
thank you all for the responses. I will pick up a thermometer this weekend and check it out. I believe that the fan belts are working well. By that I Mean that when the machine is on, the fan is spinning. it seems to work fine until under load and even if I back it off and let it Idle, the temp continues to rise over time. it takes about 30 minutes of use to overheat. Once the machine is off, it takes about an hour to cool down and then I can go back to work with it. I dont believe that Im loosing any coolant, nor dies it seem to show any signs of it in my engine oil. I had a friend tell me that I should take the thermostat completely out and try that. Any advice in the regard?
Taking the thermostat out is not advisable. Do you have good air flow through the radiator ? What is the hydraulic and transmission oil temp when it overheats ? Does it get hot enough to boil the coolant ? You will learn more when you get the infrared thermometer. [QUOTE="Newtoheavys, post: 825516, member: 80230" it seems to work fine until under load and even if I back it off and let it Idle, the temp continues to rise over time. it takes about 30 minutes of use to overheat. Once the machine is off, it takes about an hour to cool down and then I can go back to work with it.[/QUOTE] If the temp really does continue to rise when it is idling with no load indicates a blown head gasket or cracked head.
Don't take your thermostat out. That's a band aid, not a fix. Make sure the radiator is clean and air can easily pass through its entire surface. With the oil cooler in front, it can be a royal pain to properly clean, but if its not clean, you will overheat. The IR thermometer can also show whether your radiator is doing its job by the temp difference from top hose to bottom hose. We just spent an hour cleaning a charge air cooler on a 7850 John Deere Forage Harvester. It can be a bugger of a job and often gets overlooked because of how much of pain they are to get to and clean. It shut us down mid harvest because we hadnt realized how bad it was plugged, and you can't see into it without a step ladder because its over your head. Take your time, use the Dawn like was mentioned, and thoroughly clean out your radiator and oil cooler.
My younger brother called with a similar problem. It was overheating after a short time of use. He replaced all kinds of stuff. I asked if he put the thermostat in backwards. He had.
Any update? Were you able to resolve your overheat issue?
X2 for update ! Don't rule out the possibility of a defective water pump. Strange things sometimes happen inside them.
Look in the top of the radiator. If it doesn't have a cap on the top tank pull the upper hose and look in. Most likely on a machine that old you will find the tubes clogged. Severely clogged radiators will need to be removed and rodded out by a radiator shop.