MF 150 overheating

[ttaylor]

ok here is the deal I have completely rebuilt the cont. z145 in my massey 150 due to a thrown rod bearing. I suspect that it was overheating before this happened and was the cause of the failure. After the rebuild the motor runs like a top but overheats (new guage) after about 30 min. of idleing and dont even think about hooking the bush hog up. I have put in a new water pump, tried it with the t-stat in and out (no flow), installed a new radiator ( the old one was completly rotten), new hoses, belt,and a new 16" electric fan. I am leaning toward a leaking head gasket but, the water pump housing has z128k cast in it and I am wondering if this housing is correct and will provide sufficiant flow with the impeller on my water pump. sorry for the long post but I believe in giving too much info as apposed to not enough. any help is greatly appreciated. -Tony

 

[Masseynut(Australia)]

Not familiar with the MF 150, but diagnosis would be the same. A leaking head gasket, or cracked head should show up with bubbles in the top tank of the radiator after running for ten to fifteen minutes. Keep the radiator topped up while checking for bubbles.
Is the radiator blowing coolant out the overflow when it gets hot?
Check that the top AND bottom radiator hoses are the same temperature when it is reading hot. Then you can be sure that you are getting full circulation in the cooling system, ie.- thermostat is fully open.
Let me know what u find, Evan.

 

[ttaylor]

well the radiator burps coolant until the level is about 3 inches below the top of the upper tank. The hoses are about the same temp and there is no thermostat in the tractor, so I do not believe there is any restriction. I havent seen any bubbles in the coolant but the tractor vibrates so much that I could have easily missed them. The guage I have does not have degree markings on it it just says cold - normal - hot. I am going to check the temp with an infared thermometer, what would you gues a fair operating temp would be? - Tony

 

[Anonymous-0]

No thermostat is the FASTEST SUREST way to make an engine overheat. You need to get a good (and proper heat range) thermostat back in it before going any further.

 

[Anonymous-0]

Did you buy a gauge from MF or just a cheap gauge from an auto parts store? Did the gauge come with a sending unit? Why does the tractor vibrate so much? Can you hear the coolant boiling inside? Do you have a good rad cap? 180 degrees is the most common but 190 is also used by some. A thermometer you could stick in the rad would give an accurate reading once you put a proper thermostat in. A dealer will probably sell a better quality thermostat than using one from an auto parts store. Brass thermostats are better but are harder to find. Dave

 

[Anonymous-0]

Almost forgot. Why do you have a 16 inch electric fan? Where's the original fan? That could be part of the problem. Dave

 

[ttaylor]

thanks for all the responses. here are the answers to the questions yall posed. The temp guage and thermostat come from the parts section of this web site and was mf specific for the 150 with the z145. the tractor vibrates enough to giggle the coolant but isn't what I would concider severe. I ran the tractor originaly when first rebuilt with a thermostat in it and truthfully I can tell no differance with it out or in but I intend to reinstall it when I can tell for sure that I am getting good flow. The thermostat is new and I tested it and it works, the rad cap is a new 7lb cap. the electric fan was installed because when we got the tractor it had a diesel radiator and hoses and the water pump and housing were NOT for a z145 so once I installed the new water pump in the housing it stuck out too far to fit with the radiator in. This same type of fan has cooled plenty of 200-300 HP small block chevys I have built, it move 2000cfm of air and is a puller type.The original was a fixed 13" 4 blade type, but if there is some reason why you think it may not cool this motor I am all ears. one other point of intrest is that after it overheats I can let it sit for 1 min or less, start it up and the guage will drop 1/3 of the way into the normal range, which leads me to believe ther is a flow problem? As stated in my first post is a waterpump housing with z128k normal for this tractor, could the impeller not be going far enough into the housing to pump? thank again - Tony

 

[Anonymous-0]

Few questions. When you did the overhaul, did you take block to machine shop? Did they clean/boil out, etc? Did you have the head worked by machine shop? Have you used radiator stop leak "snake oil" products on this tractor? Cant understand what you are saying about the water pump casting and housing problems? Also, sounds like things are cobbled up a bit with the electric fan and all. Tom

 

[Anonymous-0]

Sounds like it's kind of a mixed up set of parts. Are the hoses for the rad all the same size as the diesel or does it have adaptors to make them fit? Could it be air locked somehow? Check with Continental about if it is the correct water pump. Maybe it isn't moving enough coolant? Maybe the water pump has something wrong with it. Without all the right parts, it can be hard to pin point the problem. Might be a combination of things. Dave

 

[ttaylor]

I have gotten everything back to original (z145) with the exception of the water pump housing. The mix matched parts I have mentioned were only the tip of the iceburg, you should have seen what I took out of the motor. Its a miracle it even ran. so how does one go about getting in touch with contential? Thanks - Tony