2.8l running hot

[78shane]

Have also notice that with cap off of radiator i am getting steam from radiator cap hole but its stone cold. And when i took the cap off after i turned off engine it seemed as if the radiator was pressurized now its just bubbling water out of it every so often

[erad]

You may have a blown head gasket or a cracked head. Either way, this is expensive and inconvenient. Check the fan coupling first - that is an easy task.

[78shane]

Yeh i have checked fan started car turned off and fan comes to a stop so i guess the head is coming off how do i know if it is just the gasket or the head or both

[erad]

Before you take the head off, get the compressions checked.This can be done via the glow plug holes. I have searched through my Max Elery Pajero Workshop manual, but cannot find any specifications as to what the compressions should be. Whatever, they should be roughly equal and if you find one or two adjacent cylinders with low compression, that is a fairly good sign of head problems. I recall that the 2.8L engine suffered from cracked head and valve seat problems, so sadly you may be one of many?? Hope not... There is no way to tell if it is a cracked head or simply a head gasket. If you have cooked the engine before , it may hopefully be just a gasket. The workshop manual talks about selecting the correct thickness gasket for your application.

For your sake, I hope it isn't anything as serious as this.

[BruceandBobbi]

Standard= 2840 kpa 411psi
Minimum= 2250 kpa 326psi

[TimTams]

couple of tips from having done the head myself recently (if you intend to DIY):

• It's definitely cracked - don't even waste your time getting it tested. It is never 'just a head gasket'. They crack really easily and reconditioners never bother to reco them. Most of the time they have been cracked for a long time before they really let go, even if they've never overheated - my head had about 8 cracks all through it and the pre-comb chambers were all cracked
• Buy a good quality head (around $1600) from a head reconditioner with a good reputation. Repco sell good bare heads ('kiwi' brand) but you need to transfer the valvetrain and shim the clearances - not worth the time IMO
• Buy a good quality head gasket and head bolts - preferably from the reconditioner so they can warrant the lot. Use the 3-notch gasket. Feel free to pick up a $40 top-end gasket kit for the other seals though (rocker cover and half moons). Don't touch the supercheap auto head bolts - I used those and then had to replace the head shortly after and the difference the bolts made when torquing were night and day. After 400km the SCA bolts were loose, the new ones were still solid
• Keep the front two head bolts (the little ones) - not all kits include them but unlike the main ones they can be reused
• Run a bottoming tap (an old head bolt with a ~5cm slot cut in it with the grinder will suffice) and compressed air down the head bolt holes. If you get coolant in there make sure it gets cleaned out. You want them CLEAN and DRY or the torque will be wrong
• If the timing chain is old, best to do both the chain and guides while it's all apart. Grab a Nason brand kit off eBay
• There's five seals around the thermostat housing - three small o-rings, a bigger o-ring, and a thermostat seal. Replace the whole lot including the thermostat itself if it's old. Make sure to clean the surfaces the o-rings go into - i had to scrape corrosion and residue away. Scotchbrite wheel on the bench grinder cleans up the mating surfaces nicely or you can labour away with a razor. The bigger o-ring on the underside was a pain, I used a little gasket goo just to hold it into the housing while I positioned it
• Cylinder heads are heavy

Sorry for the wall of text. These were all points I learned the hard way with my NJ, having about 350k km on it

[78shane]

And after all this it turns out it was the clutch fan and i could have prevented all of this, oh well live and learn

[78shane]

So fitted new clutch fan not overheating anymore.....if head is gone can i still drive it and how long will it last??

[TimTams]

So fitted new clutch fan not overheating anymore.....if head is gone can i still drive it and how long will it last??

glad you found the cause! If it's not overheating now then hopefully it should be fine.

[NK3500]

Hi 78shane, how did you work out the fan clutch was the issue.I'm having some problems with elevated temps under load lately, and suspect the fan clutch.I had a new radiator fitted a year ago. NK 3.5 DOHC Auto
Cheers

[78shane]

When engine is at normal engine temp turn engine off and see if the fan continues to spin if it does then the clutch is gone or stick a roll of newspaper in there and see if u can stop it, on mine when cold it stopped immediately after i switched it off and couldnt stop it with a roll of paper but when hot it continued to spin and i could stop it easilie when running

[NK3500]

Thanks I'll test it out.
cheers

[bilgeboy]

go easy on the bolts when you replace the clutch fan, the kits dont come with them. the AC fan will come into play if the engine gets hot also, I recently replaced mine for $35 off an alibaba store. they are $200 if you can find one locally. check your shroud is fitted,clear out the crap if any at the front of the radiator. these engines have very little tolerance to excessive heat, so doing all you can to keep it cool will help. top mounted intercoolers are counter intuitive as they absorb engine heat, and become inefficient on hot days and cause heat soak. youll notice this in a lack of power due to lower oxygen in hot air. you stick your foot in more and make it even worse, all contributing to possible overheating and weak points in your cooling system.

to test if your head is cracked, open the radiator cap when cold. run engine and check for air bubbles. your water reservoir will vent when hot and it will eventually purge all the water out of your cooling system. Not the cause for all instances but that one is a dead giveaway. x2 on buying a head, get a complete one with the valves already fitted. you can do the oil pump while you are in there as well. also get a genuine timing chain! worth the extra few bucks.

or walk away from it, they are an awful motor, and they are getting pretty old now.