Cracked Block?

Hi,
hope you can help i am a novice !!!
I have a 1993 4.2 LSE, loosing coolent.So took it to the Garage and they said Head Gasket.So paid the price and had it done.That was just after Christmas.Now in mid March Still loosing coolant {no visable leaks) Heater not getting hot,grey gunk on the sides of the exspansion tank.Engine slight misfire when running on petrol{sorry Petrol/LPG}Now i have been told that it could be a Porus Block?If so would a sealent work like the ceramic one i have seen on an auction site that starts with E.
Hope you can help Wisker

irontite would be your best bet. and welcome to lz..

Cheers for that..

sell it after and get a real landy...

Ace So i will buy a TATA!!!

wisker said:

Ace So i will buy a TATA!!!

Click to expand...

no buy a tdi.....

wisker said:

Hi,
hope you can help i am a novice !!!
I have a 1993 4.2 LSE, loosing coolent.So took it to the Garage and they said Head Gasket.So paid the price and had it done.That was just after Christmas.Now in mid March Still loosing coolant {no visable leaks) Heater not getting hot,grey gunk on the sides of the exspansion tank.Engine slight misfire when running on petrol{sorry Petrol/LPG}Now i have been told that it could be a Porus Block?If so would a sealent work like the ceramic one i have seen on an auction site that starts with E.
Hope you can help Wisker

Click to expand...

Firstly there is no such animal as a porus block. Cracked block yes porus block no. A porus block would be leaking from new. What happens is in the casting process if the block cools unevenly (thinner parts cool more quickly than thick ones) stresses are set up within it. The blocks are supposed to be put through an annealing oven where the temperature is raised and held for a time then there is a long cooling period to even out all the stresses. If this is not done properly and stresses exist. After certain parts of the block are thinned even more by machined and put into use the constant cycle of heating cooling causes the streses built into it to crack thinner parts of the block. That is when you get coolant leaks. If there is gunge in the water that can be caused by two things, short journeys were the engine does not reach running temp for long enough to get rid of the moisture drawn into it as it cools. A blocked breather can also cause this. Or oil leaking from an high pressure source into the water. If the crack was between a oil return (low pressure) there would be water in the oil. If you are losing water and you have a cracked block where is the water going? Do you have clouds of steam from the exhaust? If so that is a head inlet side problem and not the block. If the water is being pressurised then that is also a head problem. If you have a cracked block either water would leak to the outside, if the crack was external or into the oil if it was internal. If you have no circulation through the heater matrix it is either blocked or you have an air lock in the system. Did they just do one head gasket or both? It is quite impossible to diagnose a problem from the description given. Have you tried a new pressure cap?

firstly welcome to LZ, and please add where you are.
wammers has given a great bit of info there for you. i would be looking at the air lock firstt of all, if the garage did not fill the water system properly it is a high possibilty. when they done the headgasket, was it one or both, did they use genune gaskets, did they skim the head/s.

White smoke and water from exhaust from cold.
NO water in the oil.
I did have to replace the expansion tank as it had a split on the tank.
I have replaced the cap.
No visable water
I do Hear hissing from the expansion tank cap.

wisker said:

White smoke and water from exhaust from cold.
NO water in the oil.
I did have to replace the expansion tank as it had a split on the tank.
I have replaced the cap.
No visable water
I do Hear hissing from the expansion tank cap.

Click to expand...

You never answered if one or both heads were done. However on a cool damp morning white steam and water from exhaust is normal. But does the steam persist after engine reaches running temp? Does the vehicle actually overheat on the temp gauge? How much water is being lost over say a week?

Sorry it has taken so long to get back.
I had both heads done.
Heads skimed.
Puka Geskets.
Loosing a pint of coolent every 100 miles.
Wisker

Dodgy hose somewhere????
Pint every 100miles..

do you have power loss?

heater hose clips are loose either at the back or the awkward ones at the front, thats why you cant see a leak cos the heat from the inlet manifold is boiling it, go round and tighten the clips, and then check them again next week as well.

Thanks All

wisker said:

Sorry it has taken so long to get back.
I had both heads done.
Heads skimed.
Puka Geskets.
Loosing a pint of coolent every 100 miles.
Wisker

Click to expand...

Ok. Is the level falling below the full mark on the expansion tank or just falling in the expansion tank then staying put? Because if you put more than you should in the tank (overfill) any excess will be expelled. If you are confident this is not happening. There are a few things you can try. You do not say if vehicle overheats so i take it it does not, and you are just losing a little water. This could be just a small hose leak, they are very difficult to spot and dry up with heat of engine compartment. I suggest you get a static pressure test done. This is done by attaching a pump to the header tank and pumping in 15 psi of pressure which is visable on the units gauge. This will either force water out from where it's leaking or remain pressurised. If there is no leak then the first mentioned may apply. If the pressure drops and after VERY careful examination there are no hose or any other leaks. Take out the spark plugs and note their condition. If you have a plug that is clean it is certain you have a crack in the inlet side of the cylinder that plug came from. Try all that and then get back.

Hi all!!
I have decided to drop a reconditioned 3.9 in so that should solve the problem!!!!!
Wisker:hippie: