Engine/Transmission (1998.5 - 2002) Large Amount of Coolant Loss

[RNelson]

Guys,



I am losing on the order of a gallon of coolant for every 100 or so miles driven. There are no visible leaks on the pavement and I cannot see any coolant/water in the oil when I check the oil dipstick.



I have reviewed some of the threads on the block type. I haven't checked to see if I have the dreaded 53 block or not. If I do have that and it is cracked, wouldn't I see coolant making its way to the pavement below the truck? My other thinking is that I have a bad head gasket and coolant is being burnt off in the combustion chamber.



Suggestions? I'm starting to worry as it is getting close to colder temps here in Colorado. So far I've just been adding water to the radiator, rather than wasting money on coolant.

 

[RDHamill]

I'd think you'll want to pressure test the cooling system both warm and cold.
good luck

 

[jhoughton]

When mine first cracked I never saw any fluid on the ground. Once the crack grew to 7 inches it leaked out in as few as 20 miles. Look on the pasenger side under the truck just below the freeze plugs. Will look like dried stains. That is if it's a 53 block. Identified by looking at the drivers side just below the injection pump. A casted 53 about 1" tall.

 

[SeanM]

Well if you see no puddles, don't have a problem with the truck over heating or have coolant leaking in the cab you need the pressure test the system. Normally if you have a bad head gasket you will have combustion gases leaking into the cooling system causing it to overheat and build pressure in the the cooling system resulting in the coolant being pushed out the cap or overflow so I don't think thats your problem . I did have radiator one time with a bad core that only leaked when cooling system was under pressure. If you do a pressure test you might be able to find the leak while the system is pressurized.



I can say you shouldn't be running water through the cooling system. Diluting your coolant with water can cause problems down the road with corrosion, water pump wear and liner cavitation.

 

[RNelson]

I took the truck to the repair shop this week. They confirmed I have a cracked block (about 4 inches). I have about 160k miles on it. Any recommendations on how to proceed from here? Options as I see them: 1. New engine (probably my last choice), 2. Used long block, 3. Used short block. I'm leaning towards the used long block option, but not sure the pros and cons between option 2 & 3. I'm waiting for the repair shop to get back with me on what they were able to find. As of Friday, they were only able to find two, but both of them had the same 53 blocks.

 

[jhoughton]

Sorry to hear that. When mine cracked I was not in a rush and found a new block on ebay. The seller had the same problem but sold the truck before he fixed it. I paid around $900 for the block and the rest of the parts from Cummins ran about $1100. I did the work myself and had a rebuilt engine at 75k. I now have 97k on the truck with no issues. You can buy the block from Cummins at that time it was around $1600 for the bare block. Through them the labor was quoted at nearly $4k. It took me a couple weeks working after work and on the weekends.