Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[nordicgtr]

Hi all, I know this has been covered many times before and have read many posts on here and on the web with regards to overheating issues but I need your hel. I purchased the car a week ago and all was well until I was nearly home when temp guage shot up and the heater matrix was cold.
Long story short I needed a car that day and as it was LPG I had a look and drove it away, drove it after buying the tax, insuring it and signing the V5.Well no heat was coming through the matrix and the header tank was pressurising so got looking on the net for answers and ended up here.

The car is an omega gls 2.0 Auto with LPG conversion.

I am quite technically minded and like to tinker so I am pretty confident in tackling most jobs on a car so thought I would set off fixing the omega.

I thought the problem on the heater matrix would be the HBV so bought one and replaced it. The old one was clogged on the bottom pipe (no vacuum pipe attached) and also I replaced the thermostat, took the old one off and it was not closing properly so all in all these needed replacing anyway.The problem is that it is still over heating/pressurising.

I have flushed out the system with low sud bio detergent and to be honest think it is clean so want to progress onto where the problem lies.I have put a 50/50 mix coolant in to reduce the boiling point but it is still happening.

Now today I am trying to break the system down into component parts to systematically elimanate without causing more expense.

How can I tell if the water pump is working properly.Is there a check that will confirm its operation?

Water has been flushed through the radiator but again how can I prove that this is not the culprit, radiator is cold on initial start up with the bottom hose heating up and then the radiator is warm once the thermostat opens, so all seems to be fine there.

I am unsure if it is an airlock as I thought they were meant to be self bleeding but if not can someone point me in the right direction for bleeding it, this would be greatly appreciated.

Also as I said earlier it has an LPG conversion so even this may be proving a problem as they have tee'd into the existing cooling system hoses.

All in all the car looks as if it has been trouble in the past with bits missing and jubilee clips everywhere but I still remain positive yet causious to spend money where it will not cure it.

Can someone provide a schematic of the cooling system and breif description of how it works.I have bought a workshop CD but it is not what I expected just full of diagnostic software.

Your help is greatly appreciated.

[JamesV6CDX]

Where are you located?

With the LPG conversion - there should be no T's. The hot feed from the rear of the engine should go to the vaporisor, and then directly back to the HBV. Not saying this is your problem - but certainly a best practice.

The water pump on the 2.0 is a very easy job and it's sensible to renew the cambelt kit while you're in there.

It would be worthwhile getting a "sniffer test" to identify exhaust fumes in the coolant header tank, to ensure there are no head gasket issues causing it to over pressurise.

[nordicgtr]

Hi I am near South Shields.

could someone explain the flow of water or show a schematic of the pipe work then where the vapourisor should be peiced in as there are peices here and there with hoses with bolts in which is not filling me with any confidence. I would of thought you would have to keep the flow in tacked and but putting bolt in hoses going to no where this will not be the case.

once the car heats up the radiator is hot, matrix is blowing hot air and the temp gauge sits around 95. Now at this temperature I would of thought thermostat would be open constantly.if you leave it running the fan goes on and off as you would expect and the temp drops back to around 94 and you can (not recommended) realease the cap slightly which shows the air going into the header tank from both the thermostat overflow and radiator overflow pipes bubbling the coolant mix to a point where it settles but if the cap has been left off will erupt like a volcano again when it gets near to the point of the fan coming on......is this normal? Also once you switch the engine off and realease the cap it sounds like air in the block as well crackling away so cannot be good.

There is no oil in the water, no sniff test has been done yet. Just want to be sure of a few things before I have to give in and take it to a garage.

Can anyone supply or point me in the direction of the cooling configuration/ components on a 1998 X20xev similar to the electronic parts catalouge pictures.

From there I would be able to work out what the configuration is at the moment and clarify it is correct before putting it into the garage.

Also is there a way to check the pump is pumping (removing the  thermostat and turning the engine over?)

everyones help is greatly appreciated before I end up spending more hard earned cash.

[Abiton]

You'll have to forgive my dismal artistic skills, but here's a sketch that may help you of the coolant pipework on our '96 2.0:


All pipes shown are external to the engine block/head.

Ours doesn't have aircon, so no HBV.
I think all my flow arrows are correct.
WP obviously stands for Water Pump, and pushes water up through the engine towards the 3 outlets, the heater matrix one at the rear, the thermostat housing on nearside of head, and the other flange on the offside of head.
TB stands for Throttle Body, and there are two heated bits on this, the infamous small breather jet, and the body itself.

Having the expansion tank boil over like a volcano if the cap is removed at full operating temperature is not surprising, as you are de-pressurising the coolant and lowering its boiling point.

How hard are your radiator hoses when up to temp?
If they feel really hard, like you couldn't possibly flatten them with finger pressure, you may need to check for HG probs. 

Hope this helps.
Pete
 

[nordicgtr]

many thanks for the drawing.I have air con on mine but should be able to work out the flow from your drawing mate.Many thanks as it has helped greatly in piecing together where things go and components in the system.

Many thanks Abinton.