engine coolant

[Roger]

Due to change the coolant.
Just wondering what's suitable for late 95 3.1 MU, and what are you using?
Cheers.

[justin]

Just did mine on the last weekend, flushed the system & the expansion tank and used approx 8 litres of Valvoline G-05 premix which is about the middle price stuff. J

[Witchdoctor]

At the last change i put in Tectaloy 90 Plus.Cheers

Dave

[IsuzuMu]

My expansion tank is always empty. If I top it up it's all gone after not long, say a week or two. Assume this is not the norm??

Part of my last service was a pressure test and nothing was mentioned by the mec. so assume no big drama?

Any ideas what the deal might be here?

Thanks all.
Adrian.

[justin]

Well there is obviously a leak somewhere, do you ever find pools of coolant? Check the rad, and the tank and hope its one of those and not somewhere in the block. When you take the rad cap off can u see any oil floating on top of the coolant? Definitely would get it resolved before you do any long haul drives. J

[IsuzuMu]

Thanks J,

No pools of coolant, can't recall seeing any floating oil but will have a good look this weekend.

This has been happening since I bought the car 3ish years ago. Have done plenty of long hauls including Melbourne & Brisbane without and probs...

Thanks for the tips, will let you know what I do/don't find.

Cheers,
Adrian.

[geeves]

Also check that it is not overheating as this will cause the tank to overflow when hot then when it cools theres less water. Also check for bubbles in the radiator both cold and hot Be carfull with this test and good luck

[MattMU]

Mate, I have had my MU for years and I have been chasing little leaks nearly constantly. Doesnt change that I have done 240k km in it and the hoses have needed tobe replaced a few times.

The thing with MUs is there are a heap of hoses and areas for leaks to go unoticed. If you change your coolant, put a good castrol coolant in and if there is an external leak, it leaves a white powdery stain evident.

There is a coolant hose that wraps around the rear of the block from the oil cooler and another under the thermostat housing that are hard to see, had leaks from both these. The others are the heater pipes at the firewall and the little turbo coolant line running behind the Aircon compressor.

If you find any of your hoses perished, they are all too old and you should invest in a complete set of hoses!!!

Small price to pay compared to a $4k engine!!

Oh and there is the chance that the heater core is leaking in the interior of your car too. Just a thought if you have checked everything else and are still searching, rare but possible!

I doubt its internal, I have run mine out of coolant a few times and still going strong!! Prob just hard to see the leak at the moment!

Goodluck.

Matt.

[justin]

Hey Matt did you ever get your lift shackles?

[MattMU]

Justin said:

Hey Matt did you ever get your lift shackles?

Hey J, Mosy certainly did. Didnt give me much more height just better height! I will explain!!

I had replaced the rear springs with H/D Rodeo springs and then used air shockes to lift it up a little more. Now with the shackles I can drop the air out of the shocks and keep the same ride height while softening the ride altogether.

Now I can adjust the heigh depending on load and still keep a nice ride quality.

Still want those front A arms and locker and then I will be content.....finally!!!

That way if I ever do the unthinkable and change over to a Rodeo (family thing) then I can swap all the goodies, LSD disc diff rear, suspension, locker front, intercooler etc etc etc and have a good Rodeo!

Hows your 'slush box' MU going J?

[justin]

Slush box MU? Mate my girl does not like to be talked about like that. J

[Roger]

As mentioned in a reply from the head gasket post- How do you bleed the air from the coolant?
Cheers.

[justin]

According to the manual, you fill up the rad and expansion tank, leave the rad cap off and idle the motor for 3 mins, topping up afterwards. You can see the air rising and the level in the rad drop as it idles. I have always done this with both my MU's and never had an issue. J

[Roger]

That's pretty standard. I thought there was something else involved.

Cheers.

[justin]

Well not according to the Haines workshop manual for the 4JB1T, and I can't see the 4JG2 being that different. Matt mentioned air getting caught in the thermostat but I can’t see any procedure explained to alleviate or prevent this? It's looking like it has nothing to do with my engines demise either, as the mechy, (who ain't had chance to properly look at it yet???), seems to think that the problem is with the glowplugs. ???J

[MattMU]

OK, I had a few times with the old 4JB1T that after fillign her up and running it for a few minutes, believed all the air was out! It certainly wasnt and after the first drive the coolant just turned to an airated froth!!

The reason is if you fill with the top radiator hose connected I find that the coolant flows into the top hose at the same time, allowing the system to fill from the bottom up! ie you want to fill the radiator and then fill up the engine from the lower hose expelling all the air (very slowly) through the breather in the thermostat.

Then when you have fliud flowwing out the upturned top hose you know there is little chance of any air being caught inside!!

Connect the top hose and top up the last bit!

If you are still in doubt then you can rip out one of the temp senders in the top and check!!

Easy, well a little bit labour intensive but worth the time I believe!

Matt.

[justin]

I knew you'd have a good reason for that mate. Know anything about over heating the glowplugs on your motor? J