I have a B7200E with a D950 engine. When I mow for a while then stop and shut off the engine the radiator boils over some out of the overflow tube. Sometimes it does it while I'm mowing. I've changed the thermostat and it didn't help. Can someone tell me what I should to to isolate the problem? What do I do to exclude the water pump or radiator. BTW, the fan works great, belt is tight. Someone please help, I can't afford to let the dealer do the work for me. Thanks in advance
B7200 Overhheating Problem
- Thread starter blalockw
- Start date
I would check the inside and outside of the radiator to see if it is plugged up. It may look clean on the outside from a side view but could be very dirty when looking head-on. You can normally get the radiator boiled out and pressure tested for under $100 if the inside cores look plugged up. If you do determine that the fins are dirty on the outside, make sure to spray from the back side and out the front side. Avoid anything too high pressure.
The water pump sounds like it's doing it job if the water in the radiator is getting hot enough to overflow. If it has been doing this for a while we could rule out the possibility that it's still trying seek it's own level.
After it cools down, how much coolant has been lost?
I have a B8200 wth the D950A and brushhogged for 5 hours 2 weeks ago and not a drop of coolant overflowed. I had the radiator boiled and pressure tested when I got the tractor. So far so good.
Hope this helps.
The water pump sounds like it's doing it job if the water in the radiator is getting hot enough to overflow. If it has been doing this for a while we could rule out the possibility that it's still trying seek it's own level.
After it cools down, how much coolant has been lost?
I have a B8200 wth the D950A and brushhogged for 5 hours 2 weeks ago and not a drop of coolant overflowed. I had the radiator boiled and pressure tested when I got the tractor. So far so good.
Hope this helps.
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First, thank you very much for the advice. I probably lose somewhere between 10 and 16 ounces of coolant each time. It only takes running the tractor long enough for the coolant to reach boiling temp. I don't understand why you say the water pump sounds good, can you explain because I just don't understand.
The radiator does look ok, Ill wash it out from the inside in the morning. Let me know what else too try if you think of anything, I need this thing running and don't want to blow the head. Thank you so much again, all help is greatly appreciated.
The radiator does look ok, Ill wash it out from the inside in the morning. Let me know what else too try if you think of anything, I need this thing running and don't want to blow the head. Thank you so much again, all help is greatly appreciated.
blalockw,
My thinking is that if the pump is working, it is circulating hot coolant out of the engine and into the radiator where it's not properly being cooled and once all the coolant has reached that high temp it overheats/expands and leaks out.
Hopefully someone else here can shed some light on this too if I have overlooked anything.
phil
My thinking is that if the pump is working, it is circulating hot coolant out of the engine and into the radiator where it's not properly being cooled and once all the coolant has reached that high temp it overheats/expands and leaks out.
Hopefully someone else here can shed some light on this too if I have overlooked anything.
phil
That certainly makes sense, can I pull the radiator hoses and run water through the radiator to see if its clogged? Will that tell me anything? Thanks again,
I have the B7200 Hst. disel. Mine has a removable screen in front of the radiator. I allso don't have a thermostat in line with the manifold. It may
have had one in the past but seems to work well with out it. The last time I
lost coolent I cleaned the screen and checked for the thermostat.
Just what has worked for me...
have had one in the past but seems to work well with out it. The last time I
lost coolent I cleaned the screen and checked for the thermostat.
Just what has worked for me...
If this has the original radiator cap try replacing it. That may work hopefully. If not you can take radiator hoses off and take thermostat out and backflush the engine block and radiator both. I would change rad. cap first make sure it has 50/50 water and antifreeze or it will heat up if not mixed properly. handy
I would say that handy is all over your problem. I went thru the same thing that you are going thru with my B 7100 and the radiator cap fixed my problem. If you haven't changed the antifreeze lately you should do that as well. Even though antifreeze won't freeze it does loose it's ability to disapate heat and needs to be changed every 2 yrs unless you are running extended life coolant but even then most of those need extender added to them to be able to get the full benefit of the extended drain.
I have already changed the radiator cap, didn't work. Mine does have the screen in front of the radiator, it looks good but I will take it off and clean it.
I'm going to try everything everyone has mentioned and see if I can knock this problem out today. Thank you so much to everyone, I really appreciate the help. I'll let you know how it turns out.
I'm going to try everything everyone has mentioned and see if I can knock this problem out today. Thank you so much to everyone, I really appreciate the help. I'll let you know how it turns out.
Is it possible that you are simply trying to keep the radiator too full? The B7200 doesn't have a coolant recovery tank so it is necessary to maintain an air space in the rad to allow for the expansion of the coolant as it heats up. the proper full when cold level is roughly halfway on the upper radiator tank. Likely 1 to 1 1/2 inches below the filler neck. In fact, if there is coolant above the tubes when the engine is cold it is just fine. A coolant recovery bottle is a great upgrade to make on any engine that doesn't have one because it does then allow you to fully fill the rad which cuts down significantly on corrosion inside the cooling system ( water pump, freeze plugs etc)
Ed
Ed
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Keeping the radiator too full? Yes at times, but when I noticed this problem apparently the water had gotten REALLY low because nothing but steam was screaming out of the overflow tube!! It scared me to death, I thought surely I had blown the head. But everything seems ok.
I just got done pulling the screen and cleaning it, pulled out the thermostat and washed out the engine and radiator, nothing seemed to be blocking the path of the water. I did notice some significant blockage on the radiator right behind the battery of which I could not see with the battery installed. It was about the size of the fan pulley. I don't know if that could have been the problem or not. I put new antifreeze 50/50 in and I will run the tractor later today and see if I'm good. Again, thank all of you guys so much, you've been invaluable help. I'll post later today or tomorrow and let you know how it went.
I just got done pulling the screen and cleaning it, pulled out the thermostat and washed out the engine and radiator, nothing seemed to be blocking the path of the water. I did notice some significant blockage on the radiator right behind the battery of which I could not see with the battery installed. It was about the size of the fan pulley. I don't know if that could have been the problem or not. I put new antifreeze 50/50 in and I will run the tractor later today and see if I'm good. Again, thank all of you guys so much, you've been invaluable help. I'll post later today or tomorrow and let you know how it went.
blalockw,
If the coolant is getting really low, make sure you check your oil for antifreeze just as a precautionary action. This is probably NOT the problem but just exploring all possibilities.
If the coolant is getting really low, make sure you check your oil for antifreeze just as a precautionary action. This is probably NOT the problem but just exploring all possibilities.
I've looked at the oil, I don't see anything out of the ordinary, what should I look for?? That brings up another question, I can't get a good reading on the dipstick. Every time I clean it and put it back in there is oil all over the thing, I can't see the true oil level. Any ideas??
blalockw,
Is it possible that there is coolant in the oil and that is why it is reading high on the stick? I assume you are checking it while the engine is off and has sat for a few minutes?
Is it possible that there is coolant in the oil and that is why it is reading high on the stick? I assume you are checking it while the engine is off and has sat for a few minutes?
I don't know, sounds like it could be. Wouldn't I see some other symptoms if the head gasket is blown? Could it be something else?? Cracked block? Somebody chime in here and let me know what to do!!!!!!!! Thanks,
I guess you could drain the oil into a clear container so you can see if there is any water in it, it should be on the bottom if there is. Look for a milky color. Change the filter too. Refill the oil and check several times while filling to see if the dipstick is reading correctly. Put in about 3.5 quarts and check it. Should take around 4 total. It also helps to put some oil into the new filter to prevent a dry start, Be sure to include the amount of oil you put in the filter in the total you put into the engine so you don't overfill.
Great idea, thanks. I'll do that first thing tomorrow. Wish me luck, I think I need it at this point. Thank you again for all of your help and advice,
I know what you mean and I have the same problem at times. Most of the time if you wipe the dip stick clean and then check it it will have oil way up on the side that is facing the engine but if you turn the dip stick over and look at the oil level on the bottom side of the stick it will give you a good reading. It works for me on my tractors anyway, maybe it will work for you.
If you let the engine set for a while and then crack the oil drain plug it will show if there is coolant in the oil. Anti freeze is very slippery and will leak out the loosened drain plug. If the engine has been run with much antifreeze in the coolant then it will be emulsified in the oil and it will be a milky color.