(Home) Head/gasket symptoms

Can anyone help please?
I bought a Townace a couple of weeks ago with a blown radiator. The garage had said that it had a blown head gasket.
After fitting a new radiator, cap and thermostat, it starts and runs well. But, the water expansion tank breather blown out air/gas. There is obviously considerable pressure to lift the radiator cap valve from cold. It also seems like the water is not circulating because the top hose and small part of radiator gets very hot, but lower down remains cold. Yes, I am confident that there are no air traps, and no blockages, I washed everything through with a hose. If the head gasket had blown, or the head had cracked so as to blow exhaust through into the water, then surely it would be difficult to start, run lumpy and water would drip from the exhaust? A mechanic friend said that if it were a head gasket or crack, there would be obvious signs.
It’s driving me crazy! It doesn’t seem to stack up. I don’t want to take the head off unnecessarily.
Anyone got a possible explanation, please?
- (#11474) Jason Marsh, 11 Jun 04 15:33

Its possible for it to draw air into the system on cool down when there is a vacuum effect in the system.
Check the pipes from pressure cap to expansion tank and the pick up tube in the tank.
Then bleed all the air out the system and take it for a long run. If no probs on the run it could be a draw back problem.... which will be clear in the morning if its full of air again....
Otherwise its probably head gasket/cracked head...

- (#11474) chris turner, 11 Jun 04 15:43

check your thermostat as ours dusted jammed shut and blow the head cracked it.and ours would start first pull and ran great exept it would through out 2lt of coolant from cold in 1 mile

- (#11474) jason, 11 Jun 04 16:43

When my Hiace shat it self the symptoms were glaringly obvious, the fountain in the filler tube, overheating coolant loss, tears , sounds of sobbing coming from the cab......
If you are in any doubt take it to a garage and get them to sniff the coolant, if there is any exhaust fumes in the coolant it will be obvious immediatly.

If you suspect the water is not circulating do not use it until you have proven it to be ok.

I feel your pain, oh yes.

- (#11474) Master_Simon, 13 Jun 04 03:41

Thanks for your sugestions guys.
Strange that it blows air/gas so hard through the expantion tube.
I have had a couple of different thermostats fitted now, just in case, and there seems to be no blockage there.
Water flows through the radiator and engine without any problems when pouring in the top with btm hose removed.
The obviouse problems are getting the van to a garage, it is parked outside our house 7 miles away from the closest garage. I am debating with myself about having the van towed in, but I don't want an escalating bill.
Oh what to do....

- (#11474) Jason Marsh, 13 Jun 04 12:42

similar problem here caused by blocked main rad/stuck viscos fan. bottom hose cold due to blockage. top hose hot due to reduced circulation. This caused the old expansion tank to live up to its name.

Sercs re-cored the after trying to remove calcified water with costic soda soak for a week!
back flushed the other matrix and man the crap that came out of those!!.

point is if the rad is blocked with calcified water no amount of back flushing will clear it and the top being hot and the bottom being cold means a blockage somewhere dunnit?

Good luck brov
- (#11474) steve, 13 Jun 04 17:11

Thats the strange thing, the radiator is new. Taking off the bottom hose and the water drains straight through. Taking out the thermostat and blocking up the btm of the radiator and the water flows freely through the engine.
I can only think now that it is a head problem.
I am in the process of removing the head, but I can only work on it some evenings and weekend (The interior is cleared out). It may take some time, unless I can find some local help!

Anyone know someone around Cambridge (Newmarket) who might want a private job. Or a flexible garage/mechanic?


- (#11474) Jason Marsh, 14 Jun 04 06:42