Coolant

[Mudrun]

Hi all
New 08 ns vrx 144000ks full service history auto 5sp
problem ! Coolant is a dark sludge with foam bubbles
? What may have caused this
Thought someone has Mixed 2 different coolants
Or head gasket leak oil on dipstick is clean have not done oil change/
inspect yet
? What type coolant does this model run from factory
Do i need a factory thermostat or is aftermarket ok
Thanks Phil

[spot01]

Check inside of oil filler cap for milky sludge.
Check using torch that the valve gear inside looks nice & clean.
Is there an oily residue inside the coolant overflow bottle?

[Mudrun]

Hey champion
The valve gear looks fine the oil filler cap has burnt oil residue but no milky residue
The coolant bottle is a sludge pit which foams up when you swill the suc tube there does not appear to be oil but it is a dark colour couldnt see oily slik

[spot01]

I'd probably start by draining and flushing a few times (using clean water and running it until hot between flushes) to try to get as much of the crud out as possible. Don't run it for too many kms with just water, as the coolant may lubricate the water pump in some cars.

There are a few good threads on here re how to drain & flush properly - air locks are an issue to be wary of in these - try searching using google rather than our search function & include "pajero club vic" in search string.

Original coolant is MMAL genuine part - unsure what type it is, but threads will advise if you want to use non genuine. I'd use a genuine thermostat as not too costly & then you know it is the correct spec. Think about new hoses (& belts) whilst you have it in bits.

[disco stu]

One possible issue could be the auto trans cooler in the radiator leaking oil into the coolant....Had that with a falcon. It was light chocolate color in the coolant though

[spot01]

One possible issue could be the auto trans cooler in the radiator leaking oil into the coolant....Had that with a falcon. It was light chocolate color in the coolant though

Very rare, but there have been a couple of Pajeros with this issue - they have 2 auto coolers (one in the radiator & one in front of the radiator)- might be worth checking the trans fluid looks Ok?

[disco stu]

Definitely not rare with the falcon I've gathered! I was lucky that the pressure of the auto pushed trans fluid into coolant rather than the other way around. Went through all hoses fairly quickly after that-I assume the oil affected them. Weird thing degreasing coolant system!

[Hill]

2x Spot01

Check the simple things first.

Hill

[spot01]

Definitely not rare with the falcon I've gathered! I was lucky that the pressure of the auto pushed trans fluid into coolant rather than the other way around. Went through all hoses fairly quickly after that-I assume the oil affected them. Weird thing degreasing coolant system!

Yes, common with Falcons, rare with Pajeros, but possible.

[mr_bosman]

Could also be engine oil cooler - refer here:

https://www2.pajeroclub.com.au/forum/showthread.php?t=24776

&

https://www2.pajeroclub.com.au/forum/showthread.php?t=62987

[csimic]

yep that is what is is lower radiator leaking auto

I bet it is the issue auto trans cooler in the radiator leaking oil into the coolant. Get that checked out under pressure that is what it will be 90% sure regards mick

[disco stu]

Is it even worth checking it pressurised? My opinion is to just bypass it and run an oil cooler in front of radiator. If cooler already there then just bypass radiator which I would do whether there is an issue or not to keep transmission cooler

[Daniel-J]

Perhaps there is some rubbish and sludge, try washing everything well.