I have an old CAt D5B, 3308 motor that has sat for a long time with well water(high calcium content)/anti freeze in the radiator. Have used it sporadically over last 10 to 15 years, but recently the temp guage had been slowly rising to close to red line. When I let it idle, it would not cool down. Recently ran a gallon of CAT radiator flush through it. noticed it got hot somewhat slower and when quit pushing and let it idle, temp did back off toward normal, so apparently did some good. was thinking of taking radiator out to get it professionally rodded out, but real hassle doing that. Any ideas of further steps to get possible calcium out of the radiator/block before I refill with distilled water/anti-freeze? I don't use it much, just a ranch dozer, but getting ready for a minor project that I don't want to worry about temp overheat while I do a couple of acres of clearing. Thanks! Gray Eagle
2 methods that I use occasionally: get a rain barrel and fill your radiator up with that when you're going to use it. Then drain it out when you're done, repeat until the water comes out without any sediment, then let the water sit overnight and drain it cold a few times. Don't do this if there's any chance of freezing. Second method, disconnect both hoses from the radiator, stick a running garden hose in the filler, stuff a rag and an air blow gun in the bottom of the radiator. When the water runs out the top of the radiator, give it some air. Repeat until all the loose stuff is blown out. One fill of well water won't clog it up, there's not that much mineral in the water. But if well water is added over time, that does it.
You might need to run some Nalcool or other block cleaner if you think the scale has really set up.
Is the water pump working? How about the t-stat?
That and check that the fan belts are not glazed and /or slipping from some other reason.
Cummins restore or restore plus... I recall one being an alcaline base, the other acidic. If you check the ph of your coolant you can clean the insides most effectively. And I'm not overly familiar with the little 5b dozers, but do they have transmission heat exchangers like the rest of the range of cat dozers? Might be worth a check of the trans filter furring up. Just a thought, that's once you've confirmed the remainder of the cooling system is good.
Test the radiator cap pressure. My 977L was doing the same thing, I pressure tested the cap, no good, new cap no more problems.