help! 95 2.5td overheating underload

[84mksd33t]

hey guys

i got a 95 dual cab triton.
when it is powering up hills, and doing reasonable beach work, she will get really hot - like 3/4 and higher - it is only when under load, sitting around doing sfa is fine - no it isnt blocked radiator cuz i have had it flushed.

i have checked thermostat - but i cant find it!!! its not in the block where it usually is on nissans....(top hose into head BAM thermostat) not with my mitsu (are bits missing??)

could the clutch fan be gone? the clutch fan went on my patrol, but it would overheat when just being driven normally.

When ya backoff with my triton, to say 80ks the temp will drop back down, but as soon as u put her under load it will rise again, very quickly.

it has done 190,000ks.

any help is appreciated - heres a pic

[/list]

[Bidrman]

Thermostat is located on the outlet of the water pump, where the bottom hose connects. Also would reccomend a true radiator clean, remove top and bottom tanks and a rod out of the tubes, not just a flush.

Thermostat would be a good start, replace it for peace of mind.

Dave.

[84mksd33t]

thanks for that bidrman - pulled the thermostat out - it looked pretty buggered - the little seal at the top was eaten away.

going to drive it for a while without thermostat and see how she goes as it pretty bloody hot over here in WA

[hairy one]

So how is the heating problem now since you've driven it a bit?

[Bidrman]

thanks for that bidrman - pulled the thermostat out - it looked pretty buggered - the little seal at the top was eaten away.

going to drive it for a while without thermostat and see how she goes as it pretty bloody hot over here in WA

That would be a big no no, get another and stick it in, they do not like running without one, head problems will follow soon if run for too long without.

There are two different temperature thermostats available, see if you can get the cooler one.

Dave.

[-Scott-]

There are two different temperature thermostats available, see if you can get the cooler one.

Dave.

No. "Cooler thermostats" may be required for some vehicles, but Mitsubishi cooling systems are excellent, and overheating (in the circumstances described here) is a sign of a fault.

Installing a lower temp thermostat means the engine runs at a lower temperature than intended. Don't do it.

Find the fault, fix it properly.

Scott

[NJV6]

I'm with Birdman - Do a proper radiator clean - not just a flush. A proper clean invoves taking the top and bottom off the radiator. Then chances are all will be fine.

[84mksd33t]

Removing the thermostat has not corrected the problem - However it has helped - I do not want to run it without a thermostat for long - I can feel the car hating it already, the 2.5 doesnt like to be cold and driven, she likes a warmup.

I was doing a 110km/h (II am on 33's so its a bit closer to 120-125kph) run along teh freeway to work, which is about 10 mins under load. The temp rose to almost 3/4 by the end of the run - With the thermostat it would go further but I would back off to 80ks and the temp would drop back down.

Now I am inclined to think that it is the clutch fan. I have an MK patrol aswell, and the clutch fan died on that which resulted in high temps even when doing freeway runs.

I might lock the clutch fan up and see how it goes - Does anyone know how much a replacement clutch fan is?

[-Scott-]

It's your radiator.

Traditionally, Paj clutch fan problems show themselves at low speed. Highway speeds, the natural airflow should be sufficient to cool the radiator. This is the whole point of clutch fans in the first place; don't drive the fan blades when it's not needed to create airflow.

I can't explain your experience with the MK (other than it's a Nissan ) but I'm with Bidrman & NJV6 - PROPER overhaul of your radiator before you waste any more time and money.

[NJV6]

Now I am inclined to think that it is the clutch fan. I have an MK patrol aswell, and the clutch fan died on that which resulted in high temps even when doing freeway runs.

I might lock the clutch fan up and see how it goes - Does anyone know how much a replacement clutch fan is?

I like it how you ask for advice then dismiss it.

Get your radiator cleaner and your problem will disappear. If a viscous fan does any work at 120 - 125 km/h then I'll eat my pyjamas....

NJ

[hudson44]

I like it how you ask for advice then dismiss it.

Get your radiator cleaner and your problem will disappear. If a viscous fan does any work at 120 - 125 km/h then I'll eat my pyjamas....

NJ

Yeah i'm with NJV6.... there's plenty of air flowing through the radiator at 120km. I would pull the radiator and have it checked out.

[84mksd33t]

Taking the old girl into NatRad tomorrow morning to get a full flush and the tanks pulled off and inspected - He suggested a nasty blockage - I have remebered I took it mudding and got the radiator full of mud etc and thats when the problems started, I cleaned the outside as best I could (pulled rad out and hosed down back and front)

If a viscous fan does any work at 120 - 125 km/h then I'll eat my pyjamas.... Laughing

I am going to pull the clutch fan from my patrol and take it for a run and film the temp guage. In return you will yourself eating the pyjamas

Thanks for your replies guys - Always good to get more info and opinions!

[hudson44]

I am going to pull the clutch fan from my patrol and take it for a run and film the temp guage. In return you will yourself eating the pyjamas

Yeah it will overheat as you come off the highway from 100kmph but will stay cool while at speed.

Hope a full radiator clean sorts out your problem

[NJV6]

Or the clutch fan drives the water pump?? (but i'm no Nissan expert )

[84mksd33t]

I really do hope the radiator clean fixes my problem. I really want to install the front mount I have and increase the boost and fuel, its too gutless atm.

My patrol overheated on freeway runs, would only cool once i backed off - bloody weird because it defies the way a radiator and clutch fan works!

[84mksd33t]

NatRad checked out my radiator - 30% blocked and the core is pretty much rooted. Very rotten and dinged up.

$250 for pulling teh tanks off and cleaning it and new thermostat, or $690 for new core and thermostat.

What do you guys think I should do??

[Adomw]

New or recore radiator - that's the go

priciey I know but cheaper than cooking the donk

once it's right you can get back to abusing the terrain as God intended

the fastest way to stuff up a good engine is to not maintain the cooling system.

Ado

[J Top]

That seems a very dear Rad. The trade price for a recore on my 94 2.5 TD L200 was $260nz.
I would be pricing arround.
J Top

[84mksd33t]

Well, I booked it in, and I pick her up this afternoon. new radiator core (original tanks all cleaned up) and also new thermostat. I will give it a good flogging down the freeway and see how she goes I hope it fixes the problem, otherwise I am back to the drawing board eh?

They said the clutch fan was in good nick.

Cheers guys, and I will post up the results!

[hairy one]

[84mksd33t]

sorry guys been pretty busy
new radiator and thermostat has fixed the problem (almost)
up toodyay road in perth (massive steep hill - goes for probly 15ks) i hold it flat to the floor in 5th at around 90/10kmh and the temp goes to just above half, as soon as you back off, it cools down nicely. i am yet to test it on a beach - should be fine tho, all small turbo diesels get warm when really working them dont they?

since i have the 2" body lift, i think i will have to move the radiator down to line it up with the clutch fan a bit better.

cheers guys!

[hairy one]

So has this done the trick or only partially fixed it?

[NJV6]

Yes all turbo diesels get warm when working and 15k's flat in 5th will do that. Exhaust Gas temperatures go through the roof and I'd say for that length of time they would go to dangerous levels.

It is possible to crack heads without having ever overheated them (on temp guage) through the extreme heat created through combustion.

If you are going to increase the boost and fuel like you say then make sure you fit an exhaust temp guage to save your engine.

And if it only came up to half on your hill then your cooling is working very well. Half is where it should run all the time.

[84mksd33t]

90% problem solved i am just going to move the radiator down to come more in line with the clutch fan.

yeh exhaust temps do go through the roof - a little annoying with a turbo diesel under load - intercooling should fix this problem

i am not going to up the fuel and boost just yet - cooler months will be for that!

good to hear NJV6 i will post any more findings when i come across them!

[Leeo D]

diesel turbo engine exhaust gas temps on the exhaust housing will reach a maximum temp of about 450 deg.c. Petrol turbo engines run at about 900deg.c+ You don't need to worry about your exhaust temp on the diesel. To explain the need for an intercooler, well the exhaust housing gets hot,transfers the heat to the compressor wheel housing through the shaft and centre of the turbo where the oil line is.To counteract this you use an intercooler between the turbo and engine to bring down the air temp before it gets to the engine.why? air is more dense the cooler it gets so more air to cram into the cylinders for a bigger bang which gives more hp and torque.One other thing you should know about is that most diesel engines have liners or bores which are replaceable.The constant movement of the piston going up and down in the liner combined with the harmonics of the engine produces what is called cavitation on the liners.Eventually small holes are formed buy this action causing combustion pressure gases escaping into your coolant as tiny bubbles.This can and will cause an engine to get hot rapidly as your putting 450 degree bubbles into your coolant.This can be very hard to diagnose as the bubbles usually dissolve before they get to the radiator cap for you to see.Not like a cracked head which the bubbles you can see 9/10 times.Man what an essay.Sorry but I am a Diesel mechanic for the railways and play with big cummins every day and this is just some thing for you to be aware of when getting hot engines under load.hope this has been some kind of help for the future.

[hairy one]

I suspect that I have the wrong size injectors in my car. A 2.5 TD.
I am also told that "heavy":? H/way driving can push my temp up & it will drop when backed off fairly readily because of the injector size.

Whats your thoughts on this anyone?

PS
I don't fully understand the above cavitation in the piston & gases in the water part if the chamber if the gasket & or head are not leaking????

[loopy]

I saw your rims and tyres in this older posting picture. What size rims and tyres are they and do they fowl on the guards.

hey guys

i got a 95 dual cab triton.
when it is powering up hills, and doing reasonable beach work, she will get really hot - like 3/4 and higher - it is only when under load, sitting around doing sfa is fine - no it isnt blocked radiator cuz i have had it flushed.

i have checked thermostat - but i cant find it!!! its not in the block where it usually is on nissans....(top hose into head BAM thermostat) not with my mitsu (are bits missing??)

could the clutch fan be gone? the clutch fan went on my patrol, but it would overheat when just being driven normally.

When ya backoff with my triton, to say 80ks the temp will drop back down, but as soon as u put her under load it will rise again, very quickly.

it has done 190,000ks.

any help is appreciated - heres a pic

[/list]

[loopy]

I saw your photo in an old posting.

What size rims and tyres are they?. I tried putting on 15 x 7 from a patrol but they hit the inside of the front guards.

What do I put on.