The Fordson Tractor Pages Forum

I have finally got round to giving my major some work after doing the engine. It started burning the oil etc off the manifold so i knew it was working, although it wasnt struggling.
It was fine for about 10 mins, oil pressure ok, then water started coming out the overflow on the radiator, and the temperature started climbing, it got to just over 190 degrees fahrenheit on the gauge and I decided something wasnt right, plus the water was coming out faster!!

I reckon the radiator is blocked up, is there any way of telling? I have flushed it out, some crap came out but not as much as i was expecting. I put a hose in the top and it kept overflowing, so much that i had to turn the tap to half

Could be the thermostat that is not opening.

190F is a good temperature. Around this temperature you get complete combustion.

Best

Adrian

Henk, It hasnt got a thermostat in it at the moment!

Adrian, I didnt feel the engine was getting too hot, it was just the way the temperature went up, and the way the water came out! There is an arrow on the guage which i assumed was the correct running temperature?

Ive just done mine and it has a new rad and thermostat. It gets extremely hot. So hot you cant touch the head so i took the stat out and it runs alot cooler. If i put the stat in boiling water out the kettle it doesnt open. You have to keep the kettle on until it bounces and then it opens. Didnt think this was right so i left it out.

Hi Nick and Jim

The operator's manual says that the engine coolant should be maintained at temperatures between 160-190F. If necessary, the rad should be blanked off to maintain these temperatures. Diesel engines are compression ignition, of course. The compression creates heat, and when the fuel is injected at the top the of the stroke, the heat created by the compression is such that the fuel spontaneously combusts.

For ultimate combustion a diesel engine needs to run at a coolant temperature of around 200F. This results in complete combustion of the entire amount of fuel at the moment of injection ie at the top of the downward power stroke. If the engine coolant is at a lower temperature, say 160F, then there is more likelihood of the injected fuel not burning in its entirety at the top of the stroke, meaning that it continues to burn as the piston moves to the bottom of the power stroke. This results in less power and hotter exhaust gases, neither of which is desirable.

Does a temperature difference of 40F make a difference? Consider that at 211F water is a liquid and just 1 degree F higher it becomes a gas. So yes, 40F difference in temperature makes a big difference, and that's why personally I run my engine at 190F. It heats up really quickly under heavy working conditions and then just sits there all day and the engine sounds just as a Major engine should - it growls!

I would not run the engine without a stat. It is there to hold temperature in the engine leading to the benefits described above. I wouldn't worry about whether the stat is opening or not. Go by the gauge, which picks up its temp from the head on the engine side of the stat housing. If the gauge shows a temperature withing the acceptable range, you don't need to worry. My rad has a new core but it still leaks water out of the overflow pipe when working hard - just natural expansion.

Best

Adrian

Thanks adrian. I have decided to have my radiator re-cored regardless, because everything else is new. When I get it back, I will put the thermostat in, and then go for it again.
I understand that water naturally expands with heat, and I expected it to come out a bit, but the whole front end was covered in brown horrid water and it wasnt weeping out, it was flying out!

I will update when I get it back and try again.

That rad was 50+ years old. Re-coring definitely the way to go. By the way ......





Best

Adrian

Don't forget a couple of other things.. Worn water pump won't move enough coolant to keep things cool and (more to your description) a blown head gasket (or damaged on install etc) will blow compression gasses into the coolant and your rad will, as you describe, blow fluid out like mad.. Boil over with a cap on should occur closer to 220/230F as the cap holds some pressure and increases boiling point..

I had thought of that aswell, however, the water pump is only 3 years old and seems to circulate a fair bit of coolant. As with the head gasket of course you wont really know unless you take the head off, but i lowered the head on carefully with a pulley so I dont reckon thats the problem, plus I filled the system right up with water whilst it was ticking over and no bubbles were coming out.

On the head gasket problem. Start it cold, and full of fluid, and look in the top tank of the radiator for air bubbles. If you have them while cold then your problem is most likely a faulty Head gasket. Not as likely, but this will also happen if you have a crack in the head or similer problem elsewhere. Sleeve cavitaion, ect...