# case/IH 255 1987 model overheats



## dcalthetiger (Jan 1, 2009)

I recently had the radiator core replaced and put it back in with coolant. I ran it for about 10 minutes with no problems then stored the tractor for about 2 months. I used it a couple of days ago to cut grass and it started to overheat again after about 20 minutes. I didn,t replace the hoses or the thermostat. Do you think that should be my next step? I would hate to damage my tractor. It is a small 3 cylinder diesel engine and has been dependable through the years.


----------



## kitz (Jan 2, 2011)

sounds to me like it might be your thermostat not opening


----------



## ftorleans1 (Jul 12, 2009)

Most definately, I would change the thermostat. If your old radiator core was partially to mostly gunked up, you can be sure the same stuff is around the thermostat. If not, the age alone is enough to cause it to go bad. As long as your hoses look pliable and not showing signs of weather checking, you can probably hold off. However, if the hoses are original, you may want to replace them just to be on the safe side.

Keep us posted as to your progress!


----------



## Paul5388 (Oct 9, 2007)

I would crank it up with the radiator cap off and see if it's circulating, or if there are lots of bubbles in the coolant. Since the radiator has been replaced, it may well have a leaking head gasket from previous overheating. I just put a new water pump (from www.stevenstractor.com/ in LA) on my 254 and still have some water loss with overheating at times. It's quite possible I have a leaking head gasket.


----------



## dcalthetiger (Jan 1, 2009)

is it hard to replace the head gasket and is there breakdown on how to do it.


----------



## Paul5388 (Oct 9, 2007)

It's easier than a JD/Yanmar, because you don't have to deal with an external oil line. It's pretty basic, drain the water and disconnect any hoses that terminate on the head, disconnect the fuel lines and glow plug wires, I don't remember if the oil pressure switch and water temp switch are on the head, but if they are, disconnect them too. Disconnect the exhaust manifold, remove the valve cover, remove the rocker arm assembly, set the push rods in the order they came out and remove the head bolts by "unwinding them " starting at the outside and working in with a circle pattern. 

Installation is in the reverse order after the old gasket is cleaned off (don't leave any gasket material on the head or the block!) Check the valve guides for slop and check the valve stem seals. Use a torque wrench to tighten the head bolts in more than one stage, I normally start with the inside bolts and work a circle pattern toward the outside of the head. The valve adjustment will be very close to what they were when you disassembled, if you put them in the same holes they came out of. After everything is installed and tightened to spec., fill the system with water and bleed the fuel lines. If it runs without overheating, drain part of the water and refill with anti-freeze and check the valve adjustment.

Head bolt torque in three steps in foot pounds of torque:
12 mm bolts: 30, 60, 90
10mm bolts: 18, 36, 55

Valve clearance (cold): .010" for intake and exhaust

BTW, I don't see a rocker assembly torque spec., but I normally torque 8mm bolts to 15-18 ft. lbs. If you're consistent, you can return things pretty close, if you have to go into it again.


----------



## Paul5388 (Oct 9, 2007)

I edited my signature, but don't see where it has done anything. 

Ahh, it only does something on new posts.


----------



## dcalthetiger (Jan 1, 2009)

thanks will probably attack it this weekend if I can get my hands on a gasket


----------



## Paul5388 (Oct 9, 2007)

Good luck on finding a head gasket. For some reason Mitsubishi parts are harder to find and cost more than some other Japanese parts.


----------

