OVERHEATED !!!!!!!!! URGENT ADVICE

[Shorty40]

1992 LWB 4.2 TB42E EFI on straight LPG (210,000km)

Just got a call from my wife. The GQ has overheated

I am trying to sort this out over the phone as I can't leave work

She noted the car was 'hissing' when she started it. But drove it anyway Wasn't long before it started 'spluttering' and dieing. She then noted the temp guage off the dial !

She says the radiator seems empty - it took a lot of water form the service station.

With the water she drove it straight home and it seemed to be fine. Temp guage on about 1/4 (normal for the car)

Recently I noticed I was have had to put water into the overflow bottle when filling up at the servo.

Temp guage up until today has not been over 1/2.

No water spillage evident on the driveway.

Oil seems to be ok. Not brown or aerated.

Additional Info - car has recently been converted to straight LPG (if this helps diagnosing)

What am I looking for ?

Radiator hose ?
Cracked/warped head ?
Other ?

Cheers

Dan

BTW _ Quick advice needed as it my means of transport for Tuff truck

[roly]

cracked head maybe into exhaust

[The Big Green Meany]

Ok Im running the same set up, It sounds like you are very lucky and not
cracked the head.

Mine runs at Half and gets up to 3/4 on the freeway. If you are loosing a small amounmt of water and its nt coming from the hoses, The best to check

All the Plastic hose conections around the Gas converter and the air Cond System,I found a small leak in mine a whilke ago in that area after checking all the hoses,

Best of luck.

[Shorty40]

OK - spoke to the wife

The oil seems fine. No apparent water leaks anywhere.

The radiator took about 6 litres of water at the service station.

The overflow bottle was still about 1/2 full We have only ever put water in the overflow bottle - not the radiator. Last time the radiator was checked was before XMas when I flushed it and put new coolant in. Maybe a problem with the bottle or hose to and from the radiator

My thinking is, maybe over a long period the radiator has slowly gotten lower on water. My regular top ups of the overflow bottle have done nothing to help.

Does this sound possible ?

I will inspect all hoses and fittings when I get home. I will check inside the hose between the radiator and overflow bottle. I will then flush the radiator and refill with good coolant.

What is my course of action if, as Roly says, it is a cracked head into the exhaust ? Is that big $$$ ?

Thanks for the advice so far

[Wendle]

blow through the hose between bottle and radiator. the bottle is made from the worst plastic on the planet and bits flake off into the coolant. they then get jammed in the hose. the radiator can't vent as it heats up, so it vents through the radiator cap and you lose your coolant.
best thing to do is use a better quality overflow bottle off a different car. tupperware also works well.

[jessie928]

sounds like its your head

gasket only hopefully

when you convert to gas, this places additional strain on the cooling system because it runs much hotter, ( underbonnet temps also),

do yourself a favour and pull the radiator out and have it flushed and clean the AC condenser ( external) aswell.

Cheers,
Jes

[Shorty40]

blow through the hose between bottle and radiator. the bottle is made from the worst plastic on the planet and bits flake off into the coolant. they then get jammed in the hose. the radiator can't vent as it heats up, so it vents through the radiator cap and you lose your coolant.
best thing to do is use a better quality overflow bottle off a different car. tupperware also works well.

My bottle is cracked and shitty

Wife said the hose to the bottle was really hot

[Shorty40]

sounds like its your head

gasket only hopefully

when you convert to gas, this places additional strain on the cooling system because it runs much hotter, ( underbonnet temps also),

do yourself a favour and pull the radiator out and have it flushed and clean the AC condenser ( external) aswell.

Cheers,
Jes

Mmmmmm - how do I tell if it is the head ?

Should I be able to eyeball anything in particular ?

After I had the gas installed (only a couple of months now) the rig has run cooler

[jessie928]

you cant eyeball anything as such, but its basically visible by the vanishing coolant trick...

the thing is overheating the engine will dump heaps of coolant anyway, so check your radiator first.

it ran cooler?? hmm dats weird, because LPG brings alot more heat into the equation, teh only thing that adds cooling is the LPG converter but this wont make enough difference to ovveride the heating up..???

weird.

Jes

[matsmad]

If it gets hotter on the freeway than driving around town, then your radiator is clogged. Same happened to mine. Engine is revving more but no cooling from airflow. Found out the hard way. When the radiator was opened up, all the thin cooling pipes were full of shit. Get it rebuilt first. (Its cheaper and easier than a head job to start off with).

[jessie928]

yeah , shoudl have noted that, its much easyer to start the diagnostics with the cheaper stufff

then by the time you find the problem, you have a new cooling system

check your water pump aswell btw, and your thermustat, might be jammed.

JEs

[Tas_Dean]

Before embarking on any of the suggestions:

REPLACE YOUR RADIATOR CAP!!!

It could be that simple!

Also check that the hoses on the overflow bottle are hooked up the right way around, and that the dip tube is still attached to the overflow bottle cap.

Cheers, Dean

[CRUSHU]

as you bought a secondhand lpg system, maybe check the convertor for internal leaks. I broke a 351 clevo conrod when there formed a pool of water in the manifold while sitting at the lights from a small leak from the lpg convertor. when the lights went green, i took off, and the inertia pushed all the water down 1 cylinder, breaking the conrod. normally the engine can consume small amounts of water unnoticed.

[Shorty40]

Thanks for all the advice guys

matsmad - It doesnt run hotter on the freeway - so I assume the rad is ok

Jessie928 - Definately runs cooler now on gas than when it was ULP . Also, the water pump was replaced about 6 months ago.

Tas-dean - Will check the radiator cap - Wishing it is that simple

CRUSHU - LPG system while being 2nd hand was pretty new - I think it came off a 2004 GU.


I have flushed out the radiator (cleaner/flush and drove for nearly an hour). I am about to refill with new coolant. And for short term I will put in some radistor stop leak (also claims to seal heads)

Hoping this will get me to Tuff Truck and back

[Tas_Dean]

Now I've got a little more time:

The reason I mention the radiator cap is that if it is faulty, it may let water out but not suck any in.

Also with the overflow bottle, same situation, if the hose is not connected properly and into the water, again it will not suck water back into the radiator.

Both these circumstances are more likely given the amount of time since you checked the actual coolant level in the radiator. It could have slowly crept down, up to the point where the radiator could no longer cool efficiently, the motor overheats and squirts out the rest of the coolant as it happens!

Cheers, Dean

[blackmav]

Does it spit much fluid out the exhaust or mist on start up? if so the head is leaking into an exhaust port and that would be why the oil hasn't gone sour. My old one in the mornings ran rough and the radiator needed topping up every couple of weeks, stayed like this for months, then let go and you couldn't put the water into the radiator quik enough before it came out the back (was coming out like you turned a hose on) . Total head failure, through it out.
could be time for some bars leak .

[Shorty40]

Tas_Dean - i checked the overflow bottle and the rubber tube inside is connected fine

I will see if I can get a radiator cap in the morning.

blackmav - the exhaust seems to be fine - no probs there. I checked the oil - no probs. Then I checked the exhaust for that very reason

This leads me to believe (hope ) that it is a radiator prob as Tas_dean alludes to.

Or at the worst, I am a dick who doesnt check his water often enough Which again comes to Tas_deans answer

I'll see how it goes in the morning - I will take it for a long run. If it ok - TUFF TRUCK here I come

[Paps]

Exactly the same thing has recently just happened to my 89 Mav. l regularly checked the water bottle and it was fine, then one day the temp guage went right up and I put about 5 litres of water in i at a service station. I replaced the radiator cap thinking it just wasn't recovering fluid from the bottle but checked the radiator every couple of days and it was using coolant. It had vapour out the exshaust well. I canavassed three or four head joints and each one felt it would be a cracked head. They each had about half a dozen GQ heads in their shops. Riped it off and sure enough it was. This was at 260,000 k's. I had it converted for gas with hardened valves, seats and guides at the same time and a modification that puts an outlet for coolant into the back of the head to prevent an airlock occurring again. I took the head off and on myself and it cost $850. With the diesel like bottom end I should seev another 250000 out of it. Sounds like you may have to bite the bullet. Also, initially there was no oil in the water but evetually there was.

[Bingham]

start simple ---pressurising?///// thermostats jammed/// caps
then get more serious quickly as not long to go till ttc

[Bad JuJu]

Im with Tas_Dean on this, check or replace radiator cap.
LPG does run cooler BTW, not much but it is noticable on the guage though.

[blkmav]

Does it spit much fluid out the exhaust or mist on start up? if so the head is leaking into an exhaust port and that would be why the oil hasn't gone sour. My old one in the mornings ran rough and the radiator needed topping up every couple of weeks, stayed like this for months, then let go and you couldn't put the water into the radiator quik enough before it came out the back (was coming out like you turned a hose on) . Total head failure, through it out.
could be time for some bars leak .

Ugh that sounds exactly like mine

[mkpatrol]

Everyone is forgetting one thing, how recently was the gas fitted?

If the converter hoses are fitted with not enough flow or the converter is situated faily high in the engine bay then the converter may have had an air pocket.

This can take a while to surface sometimes.

For colder climates (like Canberra) the converter should be plumbed to the engine so it gets maximum flow which helps in stopping converter freeze. Generally if it is plumbed straight through the heater hose, not just to one side, then the warm coolant is going to get there quicker.

When changing coolant I always run the hose straight through the converter hose to flush out the air.

Might not be a problem but it is one I have encountered & is easy to check.

Also hook up a loud buzzer to warn the missus to sto when there is a problem

Ive got mine trained now so if there is the slightest noise she calls me at work so there are no more problems.

[dwaynes]

Does it spit much fluid out the exhaust or mist on start up? if so the head is leaking into an exhaust port and that would be why the oil hasn't gone sour. My old one in the mornings ran rough and the radiator needed topping up every couple of weeks, stayed like this for months, then let go and you couldn't put the water into the radiator quik enough before it came out the back (was coming out like you turned a hose on) . Total head failure, through it out.
could be time for some bars leak .

Ugh that sounds exactly like mine

Sounds like mine but only on gas not on petrol ( i should say i only notice it on LPG ) .
I havent need to top up my radiator

i am worried now as mine on startup and left to idle for 5 minutes will leave a small puddle on the ground and i only notice this when on lpg.

[Shorty40]

Everyone is forgetting one thing, how recently was the gas fitted?

If the converter hoses are fitted with not enough flow or the converter is situated faily high in the engine bay then the converter may have had an air pocket.

This can take a while to surface sometimes.

For colder climates (like Canberra) the converter should be plumbed to the engine so it gets maximum flow which helps in stopping converter freeze. Generally if it is plumbed straight through the heater hose, not just to one side, then the warm coolant is going to get there quicker.

When changing coolant I always run the hose straight through the converter hose to flush out the air.

Might not be a problem but it is one I have encountered & is easy to check.

Also hook up a loud buzzer to warn the missus to sto when there is a problem

Ive got mine trained now so if there is the slightest noise she calls me at work so there are no more problems.

Gas was fitted about 2 months ago.

The converter sits on the passenger side up pretty high ( about level with the top of the engine)

Colder climates like canberra - I live in Wagga which is near identical to Canberra weather.

When changing coolant I always run the hose straight through the converter hose to flush out the air.

Anymore advice on this one ? For a simple bloke

[mkpatrol]

When filling up the engine I remove one hose & pump the water straight in through the converter until it runs out the outlet at the engine you have removed the hose from. Basically you are filling the engine from the heater hose & the air bleeds out as the water rises.
You can do this with the thermostat out, leave the bottom radiator hose connected & the water will rise until it flows out the thermostat housing.

Same thing goes for heaters if they have an air pocket.


I hope I have stated this clearly, if I havnt I can PM you my phone number & you can call me.

[Shorty40]

Did a full flush and refill with coolant.

Water temp remains at 1/4 to 1/3 on the guage after driving for 30-45 minutes (various speeds from 60-100)

Blew all the shit out of the overflow bottle and the hose. Patched (siliconed) the bottle on the cracks etc

Replaced the radiator cap - the old one was quite perished and shitty looking.

Checked the oil again - seems fine. Level was on the "L" line. So I filled it back up (I imagine a lowish oil level wouldn't help temps either )

On startup and after running the car for 45 minutes I checked the exhaust for moisture. Put a piece of paper directly behind the pipe - dry as a bone

Everything seems to be fine

Only thing I noticed after putting in the new radiator cap is the engine revs have droppped at idle. Gone from about 750ish to about 600 Is that indicative of some other issue ?

Again, thanks for the advice and tips = fingers are still crossed that it aint the head

[blackmav]

Does it spit much fluid out the exhaust or mist on start up? if so the head is leaking into an exhaust port and that would be why the oil hasn't gone sour. My old one in the mornings ran rough and the radiator needed topping up every couple of weeks, stayed like this for months, then let go and you couldn't put the water into the radiator quik enough before it came out the back (was coming out like you turned a hose on) . Total head failure, through it out.
could be time for some bars leak .

Ugh that sounds exactly like mine

Sounds like mine but only on gas not on petrol ( i should say i only notice it on LPG ) .
I havent need to top up my radiato

i am worried now as mine on startup and left to idle for 5 minutes will leave a small puddle on the ground and i only notice this when on lpg.

I would think that if you park your car outside overnight you could expect some sooty water drops coming out the exhaust ,but mine used to do it parked inside overnight. Once the car is turned off the radiator is still presurized so it bled into the exhaust thus comming out on the next start up. Try bars leak. it worked for me.

[mattsluxtruck]

all good replys so far but with it being a GQ petrol you wont get moisture out of the exhaust. reason being the cat convertor. the second the car fires up the cat gets up to over 1000degrees internally real quick to burn off the gases. water from a cracked head hitting that aint got a hope in hell of making its way out the tail pipe. no one has mentioned the obvious yet. 1. cooling system pressure test any mechanic or radiator joint can do it for you. if something is leaking at 16lb when system is pressurised hot it will absolutely piss out at 22lb while in test. best thing about it it can be done cold so you get to have a good look around with overcoming heat and any water leaks will not evaporate on contact with a hot motor. 2. cooling system CO test. the mechanic puts a dye in your rad runs the car and the dye changes colour is carbon monoxide is present in the cooling system. ie cracked head or head gasket.
good luck hope i was of some assistance

[dwaynes]

all good replys so far but with it being a GQ petrol you wont get moisture out of the exhaust. reason being the cat convertor. the second the car fires up the cat gets up to over 1000degrees internally real quick to burn off the gases. water from a cracked head hitting that aint got a hope in hell of making its way out the tail pipe. no one has mentioned the obvious yet. 1. cooling system pressure test any mechanic or radiator joint can do it for you. if something is leaking at 16lb when system is pressurised hot it will absolutely piss out at 22lb while in test. best thing about it it can be done cold so you get to have a good look around with overcoming heat and any water leaks will not evaporate on contact with a hot motor. 2. cooling system CO test. the mechanic puts a dye in your rad runs the car and the dye changes colour is carbon monoxide is present in the cooling system. ie cracked head or head gasket.
good luck hope i was of some assistance

Shorty40 keeps us informed as i am very intersted of the outcome and to see if mine needs to be looked into more.

So when i had the car presure tested to find a leaking hose they should have noticed somthing then?

[J Top]

When engines get hot like this things change and move.
I would retorque the head, its cheap insurance.
When I retorque heads I back off the individual stud I have come to in the sequence and then torque it up as you get a more accurate tension that way, rather than just clicking the torque wench trying to over come the seal between the bolt head and the head.
J Top