- Location
- South east
Get hold of the fan and give it s shack back and forth if it is loss the water pump has had it
Old Daisy Browns don’t have what you call a ‘top tank’What do you think the rad cap does?
If there is not a separate expansion tank, the top tank on the radiator acts as one.
OK, the top of the rad might not have a tank, but that just means it is somewhere else.Old Daisy Browns don’t have what you call a ‘top tank’
The rad cap just sits in top of the rad and it’s designed to maintain pressure in the rad ( so that it doesn’t boil over) What the OP is describing is consistent with a defective rad cap.. Probably it would be a good idea to dump the thermostat as well.
Where’s are you located?Hello all
Having some overheating problems with my db 990. After about 15mins of work it overheats and it vents hot coolant out of the top of the radiator. But if I then touch the radiator it is all cold.
I have had the thermostat out and there was some nasty black fatty stuff on it, so I took it out and cleaned it. I also took the radiator off and put boiling water through it, took some radiator flush and look it sook in it for 2 hours. Water through again, remounted it. Put radiator flush in it and ran the tractor in idle for 45min. Drained and repeated. Put some need coolant in and it still gets too hot when put to work.
Before mounting the thermostat, I put it into some boiling water to test it. It opened fine. In the bottom of the thermostat it said 78, wich I guess is degress celsius. I can see, that original it should be a 82 degress thermostat. Could that be the problem? I. Also noticed, that the radiator cap didnt seel 100% when I had the radiator out and layed down to put the flush fluid in it. Could that be the problem?
I would really like to know if the water pump is working. Could I try to start the cold tractor with the tophose from the thermostat to the radiator off and without the thermostat installed? Would the pump, if it is working, push the coolant out? Or is there a better way to test it?
Hope there is one out there who has some ideas..
/Jacob
It's a vertical radiator, so it has a top tank, and that tank is bigger than the bottom tank to give some room for expansion. Since there is no expansion tank, the top is not meant to be filled up full. The tractor should run fine with a rag stuffed in the radiator opening and not lose coolant. If you fill it right to the top, it will run over even with a perfect radiator cap as there is no expansion room.Old Daisy Browns don’t have what you call a ‘top tank’
The rad cap just sits in top of the rad and it’s designed to maintain pressure in the rad ( so that it doesn’t boil over) What the OP is describing is consistent with a defective rad cap.. Probably it would be a good idea to dump the thermostat as well.
That is good news I'd say, as it's likely to be a basic problem.It is cold. The radiator is almost entirely cold after I put the tractor to work and it runs hot (on the gauge).
You forget that with DB 990’s they are old technology - no newer than 1980.OK, the top of the rad might not have a tank, but that just means it is somewhere else.
When the water expands it needs somewhere to go.
Only if you completely fill up the tank on the top of the rad when you fill the rad.You forget that with DB 990’s they are old technology - no newer than 1980.
when the water expands it goes through the overflow pipe from the filler neck and vents on the ground.
It must be diesel either injector leaking or injector washer at the bottom. If water it will dry up instantly with a hot engine I think, but I’m not a David Brown expertOkay a short update. Stress testet the tractor yesterday without the thermostat. It went hot again. I took my laser therometer and took some readings. Top engine block was 91 degress, thermostat housing 87 degress. Radiator close to the top (under the expansion part of it) 12 degress.
So I think there is still to much resistance in the radiator, does that sound right?
I also noticed some troubling thing. See attachment. It doesnt smell like diesel, so it might be water. Is that a problem with the head gasket?
So, two possibilities:Okay a short update. Stress testet the tractor yesterday without the thermostat. It went hot again. I took my laser therometer and took some readings. Top engine block was 91 degress, thermostat housing 87 degress. Radiator close to the top (under the expansion part of it) 12 degress.
So I think there is still to much resistance in the radiator, does that sound right?
I also noticed some troubling thing. See attachment. It doesnt smell like diesel, so it might be water. Is that a problem with the head gasket?
sure you need a new water pumpOkay a short update. Stress testet the tractor yesterday without the thermostat. It went hot again. I took my laser therometer and took some readings. Top engine block was 91 degress, thermostat housing 87 degress. Radiator close to the top (under the expansion part of it) 12 degress.
So I think there is still to much resistance in the radiator, does that sound right?
I also noticed some troubling thing. See attachment. It doesnt smell like diesel, so it might be water. Is that a problem with the head gasket?
Tiny little baby steps JacobOkay a short update. Stress testet the tractor yesterday without the thermostat. It went hot again. I took my laser therometer and took some readings. Top engine block was 91 degress, thermostat housing 87 degress. Radiator close to the top (under the expansion part of it) 12 degress.
So I think there is still to much resistance in the radiator, does that sound right?
I also noticed some troubling thing. See attachment. It doesnt smell like diesel, so it might be water. Is that a problem with the head gasket?
To clearify. When I did that, I had the thermostat out and not fitted the top hose back on again, so there was free above the pump. Therefore I think the pump is ok.You‘ve said previously that you took the the thermostat out and cranked over the engine and water shot out? In my admittedly limited experience that doesn’t sound right, what I’ve seen is you just see a “swirling” of water at the top of the radiator.
The fact it does shoot out that suggests some sort of back pressure perhaps caused by blockage in the radiator, I’ve previously used caustic soda to clean my system - Google caustic soda cleaning of radiators for loads of info - BUT if your radiator is heavily blocked you might not get a circulating flow through the radiator. it really might be best to take off the rad and see what happens if you stick a water hose in at the top and if it flows freely from the bottom.
You could also check the pump at the same time, I’m still not convinced it’s not part of the problem.