Correct coolant level

[Willl]

Hi all,

I've searched in vain - i can't find anything in either workshop or owners manual to tell me what the correct coolant level is.

I know how much the system holds, but I've been flushing and reverse flushing and topping up etc etc, now I've lost track of how much is actually in the system.

Is the square head plug next to the thermostat a level indicator by chance?

Thanks,
Will

[Willl]

Also I have a pressure rad cap fitted, is this correct or should I have non-pressure cap?

Thanks,
Will

[Pavel]

I'm not sure that I understand your question[s].
You remove the radiator PRESSURE cap and pour coolant in until it will take no more. After replacing the rad. cap start the engine and allow it to reach its operating temp. All things being equal [i.e. no leaks] this will cause expansion of the coolant to reach its own level and maintain that level for quite a few days usage.
The system works exactly the same as it does on your car -- unless it [your car] has a 'recovery system'; as all modern cars have.
Pavel

[oehrick]

I've been advised not to use a pressure cap, the cylinder liner O rings can become jelly like so if pressurised you can end up with a sump full of coolant

[Willl]

Thanks very much for the replies.

My question wasn't very clear, its really the pressure cap question to which I refer. I have been filling the radiator but presumably this does not give any room for the coolant to expand with the pressure cap fitted, as it would do in the header tank of a car.

I think the answer is to fill the system up and use a non-pressure cap as Rick says.

Thanks!
Will

[SvendH]

The screw plug next to the termostat housing is useful for getting traped air out of the block when refilling.

[Pavel]

All tractor radiators have a header tank otherwise the coolant would not be able to circulate. The top hose is connected to the header tank.
Ricky; the 'good book' [up to and including the Super Major] informs us that, as standard, an un-pressurised rad cap is fitted -- unless the Major is used in a hot climate [as here in Oz, although I would hardly call our mid winter max of around 12 to15C hot] The pressures mentioned are either 4psi or 7psi.
May I also suggest that the problem with cooked lining 'O' rings could be traced to a malfunctioning shrouded thermostat as fitted to Mk.2 onwards engines which permits faster warm-up times. In icy weather conditions this thermostat may not open enough to permit complete coolant circulation but instead cause local cylinder block hot spots -- good reason, I would have thought, to have a blind covering the front of the radiator.
Pavel

[oehrick]

Bang on the nail as usual Pavel

The O ring failure mode that I was warned about was the rings 'jellifying' rather than going hard, my advisor was a long time Nuffield parts dealer who sold E1A bits as a second line, while not knowing, he thought that the softening problem may have been the result of using more modern detergent / additive containing engine oils and with any coolant pressure behind them, they could squeeze out until they leaked.

Not seen it first hand but as my rocker box gasket had softened and stretched it made sense, back to a non pressurised filler and a diet of Morris' straight oil.

[Willl]

Sorry for sounding dim but I want to get this right as I am in the process of installing a new radiator.

How do I know when the water level in the radiator is correct? Presumably if I take off the rad cap when cold and I can see coolant in the hose then that is overfull? Or not?

Thanks again!

[Timeee]

Dear Will

I remove the radiator cap and check with my finger to see that the coolant level is at least one inch deep in the filler hose neck. Over the years I have found that different Majors end up with a different level of coolant. Filling right up to the top of the filler neck before starting from cold usually leads to the tractor throwing out surplus coolant through the overflow and finding its own level when it has warmed up. I usually check the level before use and twice a day when operating.
Now, a question for train-spotters, how many Majors have a steel filler neck soldered to the header tank, rather than the bracket and flexible filler hose? My 1961 Ex Dutch Super Major has one and was fitted with a mechanical radiator blind?

Timeee

[Willl]

Thanks Timeee!

In that case I will brim it right up to the rad cap, and let it chuck out what it doesn't want out of the overflow. Once that's stopped then I know its at the right level.

Great, I'll fill it up in the morn.

Thanks again,
Will

[Old Hywel]

Metal filler neck? One here, 1954 Major. Wouldn’t be too sure it’s steel though.

[Timeee]

Old Hywel

Thanks for the reply. Probably means you have the original radiator still. The filler hose is not listed in the Parts List until Jan 1955, so that would indicate that the metal filler necked radiators were fitted up 'til then. Better stop this now, or we will have to open up a new topic.

Timeee