Overheating problem

[staginmacc]

Symptoms are;

temp guage reached red in less than 5 mins.

water level in rad down slightly

expansion bottle full!



Steam coming from below carb area.

Should I suspect the thermostat is not working or is it water pump?



I have read manual and see there may be several different thermostats available.

This is the first time i have experienced any overheating in 6 years i have owned the car. Engine was rebuilt 3 years ago but i do not know if pump was rebuilt or replaced at that time. Is there a way to check what is wrong without stripping down first?



regards

Paul Briggs

[european voyager]

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Let her cool down a bit then fill up the water levels , Run her up and see what happens . Check the temp of the air comming out of the heater if the engine is warm and the heater is cold there could be air in the system.
let her tick over with the radiatior cap on and header tank cap on and feel if the hoses get hard quite quick , Id also check for leaks from hoses it could be a split hose ?

[staginmacc]

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In order to drive home yesterday i had put the heater on full including the fan but did not notice any heat coming into the inside of the car. I did top up rad beforwe driving home but it only was about half a pint to fill it up!

I stopped on the way home to let the engine cool as it was in red again.

I will try as you describe right now and see what happens If there is an air blockage will it relieve itself?

[GDPR]

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Jack up LHF of car and fill radiator through the bung and not the tank - keep squeezing the bottom and top hoses to expel air - make sure heater control set to hot - that should help clear airlocks.

As to water and steam from the vee...... inlet manifold gaskets leak, as does water pump and there are opportunities for hoses and pipes to split - so take your choice.

To fill the expansion bottle, have no heat from the heater, and to hit the red so quickly it does sound like a possible HGF though.....

Hope you are lucky and it is just minor

Russ

[staginmacc]

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Cecked rad level and started car.

Temp progressed to red. I have swicted off and now removed air filter housing to get at Thermostat housing.

I cannot see any leaks but hear the steam hissing from below carbs (inlet manifolod area or below.

Although temp guage was reading hot the air temp from heater inside was cold.

Any ideas of what to do now would be appreciated!!

[StagnJag]

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when the car is cold, how long does it take for the top hose to get hard? With no pressure in the cooling system it should compress by hand. It should stay like this until the thermostat opens. It sounds like HGF as Russ has suggested, and the pressure in the cooling system has found a weakness in the system - possibly inlet manifold gaskets causing the steam. (Leaks into the V can also be caused by corrosion of the core plug that resides in the bottom of the inlet manifold - but less likely than other suggestions so far)

Regards

Dave

[staginmacc]

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The top hose stays soft, i suspect the thermostat is not opening as the rad stays cold. I will remove the thermostat and test it in hot water and see wht type is fitted.



thanks Paul

[V Mad]

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Are you getting any coolant flowing into the rad (when engine has warmed up)? If you open the filler plug you should see some flow when you rev up. If no flow; either thermostat has jammed or water pump is not turning.

[staginmacc]

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I just removed thermostat and tested it in boiling water. It does open and is a 74 degree unit.

On topping water level back up to top after refitting the thermostat i squeezed the top hose and as i still have air filter off i can see now there is a hole in one of blanking plugs on nearside head.The hole is sizeable as a jet of water was emitted as i squeezed pipe.

Do you think just by replacing the blank it will be ok or is the fact the blank plug has holed a sign of somethng more serious?

[V Mad]

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If you mean a core plug has a hole in it, obviously the core plug needs replacing, then refill your cooling system as already explained by others.

This would only cause overheating if you lost quite a lot of coolant and you let it get far too low! Is that likely to be what happened?

I have some spare core plugs; if you let me know the size, then if I have the right oneI will pop one in the post for you.

[Stagdad]

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I suspect the 74 stat was fitted to try and stop the problem,once you have found the problem I would fit a 82 or 88 stat,74 will make the engine take ages to warm up causing unnecessary wear.

Cheers Steve

[staginmacc]

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I will remove the core plug tommorrow and measure te size.

Thanks for your kind offer.

I will be in touch

[staginmacc]

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Now removed core plug.

It is shown in Stag manual as 26.35.01 and is approx 1.125" dia and 0.250" deep.



It is the one from the near side cylinder head immediately below the carb at end closest to the bulk head.

If you do have one I would appreciate it.

Please mail me on briggsp@hotmail.co.uk



Thanks

Paul Briggs

[V Mad]

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I have a p/n 144686 that seems to be that size. Is that OK?

[staginmacc]

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Update,

Picked up set of new core plugs from Paddocks and replaced the holed one.

Checked water level and all hoses.

On start up the temp guage did not move for some time.

The engine was warmed up and running on tick over without choke and temp guage had risen to approx 10 o clock position (about 1/3 rd way across ).

This is where it had normally risen to and I was getting warm air with heater blower on.

All seems to be good.

I will take out for a drive tommorrow after rechecking the water level and see how all goes.

I am going to drain off the cooling system flush out and refill with new antifreeze and water.

Thanks for everyones help, I will be wary of coolant level in future.

I do not know if the holed core plug was the result of low coolant level or vica versa.

The engine was rebuilt with new core plugs fitted at that tome approx 3 years ago and only travelled 2,500 miles since.