is the block cracked
 

ive just had the head gasket done on my 1.8 petrol lpg 75 tourer,and now it over heats and presurises and water forces its way out of the rad cap, the garage that did the work tell me that the block must be cracked. any opinions wuld be welcome:shrug:

did they do a compression test?

they didn.t say, they put a new thermostat in it because all the pipes were red hot and presurised but when the water comes out the rad cap its cold. ive lost a bit of confidance in the garage to be honest

Have you got a PRT (pressure relief thermostat), plastic t piece near bottom of rad, cos if the garage have fitted an old type stat you will overheat, there should be just a dumby in the old housing.

yes , that is what they replaced, the thing is i drove the car for a couple of months with the head gasket blown and it never presurised or over heated and to be honest didn.t drive too bad, then when i got the money together, got the gasket done and since have had this presurising and overheating problem, why the water that comes out should be stone cold though is beyond me, im no mechanic so when the garage tell me that the block is cracked then i cant really question it

very rare for block to crack as it has wet liners i would think its a liner not seated after headgasket done if the engine is turned over when the head is off the liners move and the seal is broken you should remove the liners when doing the head and reseal them it is not a big job and it should be done every time a headgasket is replaced i do

Sounds a bit extreme to remove the liners if you dont move the crank.
If the water ejected is cold its got to be a circulation problem, stat, pump, blockage, airlock.

when changing the headgasket and lower oil rail why not spend another hour resealing the liners at least you know its done right and if there are further issues you have removed this possibiluty i have allways done it this way and i have never had one back i dont want to seem pushey but its the best way

This could be just a bad airlock due to poor coolant refilling. Drain it and refill properly and it just might cure it.
This is from an earlier post:

'Take pipe of bottom of radiator(left hand side) you will probably need pipe grips, I replaced that clip with an eclipse. Undo drain plug on engine block. When all has drained, refit engine block drain plug (bolt) smear red hermatite on the back of the bolt washer.
Replace bottom pipe on radiator. Open bleeder on top of pipe near battery box and fill slowly until water comes from bleeder with no air bubbles. Then squeeze the lower pipe on rad a few times to get rid of any possible air, and do the same to the rest of the water pipes you can see. Top up until water comes out of bleeder as before and tighten. Check level in header tank is up to max. Job done apart from taking it for a ride round until it is at running temp, than check water level.'




JCW

i agree sounds more like an airlock or blockage to me ,i bet they never bleed the system properly ..