The Mitsubishi Pajero Owners Club®

[samfishing]

Advice greatly appreciated!!!
I have a problem with my 2.8TD pajero (1996) 65,000 miles.
It keeps filling the expansion bottle, but the top hose seems empty!!!

GOOD POINTS................
It never over heats!
The oil dipstick is clean (apart from oil)
The oil filler cap is spotless!
There is no water / condensation coming from the exhaust!
It runs like a bird!
It starts first time!


BAD POINTS..................
It doesnt seem to hold water in the top hose!
There seems to be a steady stream of bubbles being blown into the expansion tank!

Even when i thrashed it about in temper it still didnt over heat!!! The temperature gauge stays bang in the middle. I replaced the radiator cap with a brand new one from mitsubushi. I run the vehicle with the rad cap off, for the first 40 seconds or so it bubbled, loosing about half a pint over the top which then turned to what could only be described as like an expresso coffee.

Any ideas what could be wrong???

Thanks for your time
sam.

[Google]

[tellyman]

Sounds like your head gasket is faulty lots on this, try search head gasket many sad storys. It needs sorting now or you will crack your head the temp will not warn you good luck

[JayCee]

I had this....

Nearly drove me nuts..
First..and most important ..

Check the water quantity at the rad cap until this is sorted ...
Or you will need a new head.

With the car hot after a run ..turn off the engine , pop the bonnet, and try to twist the fan.. there should be reasonable resistance. if not you have a weak or failed viscous fan unit ..( Not the end of the world ..a cheap fix is possible)

If the fan is ok ..

Bring the car (Or the radiator ) to a radiator specialist who will do a proper "Core Flow test" on the rad.
This is not the same as checking that water flows in one end and out the other.

Radiators age and if poor or insufficent coolant was used, the internal cores inside the rad can corrode, collapse or get clogged.
this creates areas of the rad through which nothing circulates , thus reducing its effective size .
(Imagine trying to cool a Pajero with a Mini radiator )

As the car heats up, flow restrictions and reduced cooling cause pressure build-up , the rad cap allows this to vent through into the expansion bottle.
Eventually the expansion tank overflows down the overflow pipe beside the front wheel and a wet spot is seen on the ground.

So.. excess pressure , caused by flow restrictions, causes the bottle to fill
and the rad to empty. Eventually , enough water will be lost to either cause an airlock or an overheat.

PS..
I changed the Rad cap, the pipes, the thermostat, the water pump, checked for leaks, and changed the head gasket ...

Then I figured it out... I repaired the fan and had the radiator re-cored .

Sorted... 8)

Joe

[angels.disco]

Not the easiest of things to diagnose...........

What is the colour of the water in the radiator?
if it is a sludgy brown, it has boiled at some time.

The next thing requires a little specialist knowledge

The bubbles coming through the coolant, .... if the head gasket has perished you will be able to smell carbon monoxide gasses (there is a specialist tool avialable that you place onto the top of the radiator and it analyses the bubble to tell you if there is carbon monoxide present)

As to smelling for Crabon Monoxide, it is much easier with a petrol engine, a diesel engine is a little more tricky, but it can still be done!


As a quick fix......

There is a product on the market available from motorists accessory shops that is used to seal leaking head gaskets and cracked cylinder blocks, I cannot remember the name of the product.. But I can tell you that it uses liquid glass in suspension, and I have used it many times with a 90% success rate, but you have to follow the instructions very carefully.

I don't think that it's a blocked radiator, as it isn't overheating...... to test for a radiator blockage.....drive the car until it attains normal running temperature, switch off the engine, then feel at the radiator core, it should be very hot at the top and progressively cooler as you feel towards the bottom........ usually if its blocked, it will be cold around the middle, where the centre of the fan is located.

Another way of testing for cooling system pressurisation is to fit a cooling system pressure tester onto the radiator, pressurise the cooling system to 5lbs pressure, then run the engine at about 1500 RPM.

If the pressure rises greatly, it suggests a blown head gasket/cracked head/ cracked block. one of those or more


Sorry to sound so pessimistic


Peter

[JayCee]

Hi Peter,

I had all this the bubbles ..etc..
Did a gas test .. nothing.

[samfishing]

Now now lads!!! boxing gloves not allowed!!! (only joking) nice to see you taking an interest, ive took all the advice off you lads and have decided to take the appropriate action (START PRAYING AND HOPE SOMEBODYS LISTENING)
any way im taking it back on monday for the dealers garage to have a look for me.

just another little strange oddity, Ive put a small plastic bottle on the end of the overflow pipe on the header tank, but even though it doesnt seem to be keeping water in the top hose nothing has reached this bottle and there does not seem to be any condensation or water coming from the exhaust??? MUST BE ALIENS STEALING IT!!!


Thanks for your time.
sam

[Trig]

[Ivor Green]

Guys, listen to Joe, he has spent many hours trying to sort this problem and if anyone has found a fix it's my good friend Joe , it apears that there may be a problem with thse fans , I looked at a Canter on Friday and this has the 2.8 engine , it to was overheateing and although he had done all we had recomended to fix it , the thing was still overheating , but low and behold I could hold onto the fan and it had very little resistance even though it had just been driven some 40 odd miles , I think Joe has hit on a fix , mind you when yuo see the price of a new viscous fan unit it will make your eyes water , still Joe knows a fix for that .

[angels.disco]

@ Jaycee


OR.. had ordinary water added instead of a corrosion inhibitor (Coolant )

Or ..both

[JayCee]

Peter..

I wasn't havin a go at you..
(in case you think I was )

But simply stating personal experience.
I had this problem ..on this vehicle.

[Joker777]

I had a very similar problem to this just the other week, after cleaning my paj i did a quick fluid check, and found my coolant level a little low, topped it up and then did a 60 mile round trip to a garden center (for the misus you understand) on the way back i noticed that the temp gauge was rising and falling with my speeds, it never got realy hot just higher than normal and normaly its rock steady just under half way. When i got home i found that it had totaly filled the expansion bottle and some of the fluid had then gone thru the overflow. I let it cool down did most of the things you all have described above like check the fan and for leaks and found nothing out of the ordinary, after the system had cooled all the water sucked back into the radiator as it should leaving the bottle empty and the radiator a little low, i topped boyh up and the paj has run fine since the gauge is back to its rock steady self and no fluid has been lost.

Its got me stumped to but as its ok at the mo im a little reluctant to investigate to far and up set the system again.

[angels.disco]

Not having a go at you either mate lol

As for the Dude thing, some message boards are using the new spelling of Dude....Dooooode lol

I would have said a combustion gas test would have been one of the first things I would have done on this vehicle, especially noting the sequence of events.

Sorry, but I must disagree with you on the point of the radiator being blocked, remember Samfishing said that the cooling system was NOT overheating. If a radiator core was restricted by a blockage in the warm weather we are experiencing this week there would be a definate lack of heat tramsmission to the atmosphere, and the temperature gauge would rise beyond its normal running position.

Back to the coolant thing,


{quote
Ok .. to be specific..
Ordinary plain water ..without the correct mix of coolant .. 50/50 water and a coolant with anti-corrosive properties. as per the manual.
Lack of a corrosion inhibitor will cause a sludgy brown mess in the water called rust.
Quote}



Be very careful of the concentration, you must use only the recommended concentration given by the vehicle manufacturer, and furthermore you must not use normal Ethylene Glycol antifreeze, you must use the correct type, ususlly OAT in japanese vehicles.

I have added a brief description of antifreeze types below;

There are currently five main types of antifreeze. In all cases the 'anti-freeze' properties last the life of the coolant - it is the various additives that deteriorate with time. These additives include anti-foaming agents, surfactants (to improve the 'wetting' of the coolant and hence give better heat transfer) and, most importantly, anti-corrosion additives.
As the range of alloys and plastics used in modern engines grows ever more complex it is important to ensure that the correct anti-freeze is used.

1. Ethylene Glycol (e.g. 'Bluecol') - this is the traditional stuff, used since the 1950's. It uses silicates to stop corrosion by passivating the metal surface. This type of anti-freeze is suitable for most European cars, but not Japanese cars. Japanese manufacturers normally recommend a low- or no-silicate formulation due to the nature of the seal materials that they use (see below).
Typical service life of 2-4 years.

2. Ethylene Glycol: Low- or no-silicate formulation. This is specified by most Japanese cars. OEM Nissan, Toyota 'red' etc. antifreezes use phosphates rather than silicates to inhibit corrosion. Silicates are abrasive and the use of high silicate antifreezes in Japanese cars may result in premature failure of seal materials.
Typical service life of 2-4 years.

3. Mono Propylene Glycol (e.g. Comma Coldstream) - this still uses silicates and is claimed to last 4 years. Mono Propylene Glycol does not conduct heat as well as Ethylene Glycol and currently carries NO recommendation from any major car manufacturer- and some actually caution against it. The main claim to fame for Mono Propylene Glycol is that its less toxic than Ethylene Glycol.
Typical service life of 2-4 years.

4. Organic Acid Technology (OAT) - e.g. GM 'DexCool'. Introduced in 1995, this is a recyclable and biodegradable anntifreeze which is based on organic acids and is silicate- and phosphate-free. However, due to the nature of the chemicals used, it can attack certain seal and gasket materials and therefore should only be used in vehicles for which it is factory specified.
OAT antifreeze MUST NOT be mixed with the types listed above - if you wish to switch to OAT type then the cooling system must first be chemically flushed.
The claimed service life of the corrosion inhibitor package is about 5 years, or 100-150,000 miles.

5. Ethylene Glycol-based 'Hybrid Organic Acid Technology' (HOAT). Uses Ethylene Glycol, but with OAT-based corrosion inhibitors and some added silicates; most usually BASF's "Glysantin" additive package is used (also known as 'G-05'). HOAT is less agressive than straight OAT anti-freeze and has better cavitation resistance. Halfords 'Advanced Antifreeze' is an HOAT formulation. Again, best to thoroughly flush your system if switching to it.
Lasts 4-5 years.

The bottom line is to refill your engine with what the factory supplied and do a flush-and-refill every 4 years maximum.
If you have a Japanese car, stick to the maker's brand since non-OEM coolants may contain higher levels of potentially damaging silicates.

If mixing your coolant from a 'concentrate' then use demineralised or distilled water (available from motor factors at around £3 for 5 litres) to make up the quantity - UK tap water often has a lot of dissolved minerals in it which can leave scale deposits inside the engine's coolant passages.

In the North of the UK we have "Soft Water" which does not cause any appreciable problems in cooling systems and can even be used to top up lead acid batteries.................

Hey, Samfishing, sorry if this is getting a little deep mate [/quote]

[Joker777]

Just a small note to say that an engine can over heat without the gauge showing hot if the sender unit is not in the flow of water ie if the hose/rad is empty or if there is an air lock found this out on an R5 turbo.

[JayCee]

[angels.disco]

@ Joker....


If the thermal transmitter is not in the coolant or in steam off the coolant, the temperature gauage will actually go to cold, and the heater will blow cold air when in the hot position....................................