just how hot is hot?

Submitted: Monday, Jan 16, 2006 at 14:59
ThreadID: 29744 Views:1899 Replies:8 FollowUps:4
This Thread has been Archived
After some heating problems on the 2.8TD GQ patrol and getting it fixed by NATRAD last week, I thought that I had better get a correct temp guage for the veh. Considering the turbo is water cooled I thought it makes good sense to know exactly what temp's are under my bonnet.
I have included an interesting link to show what i don't trust my dashboard temp indicator:
http://members.optusnet.com.au/markfield/stdguageVdigital.html

Anyway my question is, what temp range is "normal", what is classed as "hot" and what is classed at "dangerours" to cause engine damage? My new indicator shows 40C to 140C

Thanks,
Back Expand Un-Read 0 Moderator

Reply By: Member - Davoe (Widgiemooltha) - Monday, Jan 16, 2006 at 15:27

Monday, Jan 16, 2006 at 15:27
You dont want the water to boil as it then loses its ability to disapate heat. With 50% coolant a radiator should boil at around 125 degrees C
AnswerID: 148933

Follow Up By: Sir Diamond - Monday, Jan 16, 2006 at 17:46

Monday, Jan 16, 2006 at 17:46
You dont want the water to boil as it then loses its ability to disapate heat. With 50% coolant a radiator should boil at around 125 degrees C
so 124 degrees should be fine
lol
0
FollowupID: 402135

Follow Up By: Member - Davoe (Widgiemooltha) - Monday, Jan 16, 2006 at 20:01

Monday, Jan 16, 2006 at 20:01
I think so but you will find it will be boiling after you pull up. I reckon you know you have problems if you pull up and 10 -30 seconds later it starts boiling the Billy. And anyway he asked how hot is too hot and i reckon it is about 125 but I wouldnt just ignore it coz you would be asking for trouble
0
FollowupID: 402169

Reply By: bombsquad - Monday, Jan 16, 2006 at 15:56

Monday, Jan 16, 2006 at 15:56
And they only work when 'wet'...(reminds me, must get around to fitting my low coolant alarm........purchased after a $6500.00+ mishap....
AnswerID: 148937

Reply By: Eddy - Monday, Jan 16, 2006 at 16:37

Monday, Jan 16, 2006 at 16:37
Hi Gossy.

I reckon there is more to consider than just the water temperature.

I found the following on Ryans Ryans Radiators website a while back:

Almost one third of the heat generated by the engine must be removed by the vehicle's two cooling systems.
That's correct your engine has two cooling systems.
(1) The top of the engine: the area around each cylinder in the engine block, the combustion chamber areas in the cylinder heads and the intake manifold, dispel heat through the engine's radiator coolant system.

(2) The rest of the engine: the crankshaft, bearings, camshaft, lifters, connecting rods and pistons are only cooled by engine oil.

The ideal operating range for engine oil is 82°C through 93°C. While operating within this range, the oil works as a lubricant, coolant, and cleansing agent in the engine.
Modern engines generally run with radiator coolant temperatures between 90°C and 105°C with oil temperature ranges up to 25°C HOTTER. In other words, when the engine is performing flawlessly, the engine oil is already overheating! Oil that exceeds 105°C rapidly loses its ability to lubricate and cool causing accelerated fatigue and premature component failure.

Makes you think.

Catcha
Eddy


AnswerID: 148942

Reply By: Gossy - Monday, Jan 16, 2006 at 16:44

Monday, Jan 16, 2006 at 16:44
good point about the oil. As mentioned about the expensive mishap, this is why I have fitted the gauge. I don't want to learn the hard way. By knowing if my cooling system is running well I can stop driving, fix etc before expensive repairs are needed.
AnswerID: 148944

Reply By: Member - Trevor R (QLD) - Monday, Jan 16, 2006 at 18:28

Monday, Jan 16, 2006 at 18:28
Hi Gossy,

I was told by Nissan Aust. (for a 4.2 turbo) 118c is acceptable for short periods, ie: up ranges ect. I run a 1.1 rad cap. Don't know for sure if the same applies to 2.8 but can't see how there would be much of a difference.

Cheers Trevor.
AnswerID: 148975

Follow Up By: Member - Roachie (SA) - Monday, Jan 16, 2006 at 18:47

Monday, Jan 16, 2006 at 18:47
Trevor,
That makes me feel much better, cos the trip to the Murray on 30/12 the max temp reached was about 118oC; but it was at/around that temp for extended periods, all with no apparent ill-effects.
The oil temp did get up to just over 100oC as well (1st time I've seen it that high since fitting that gauge), but the EGTs stayed relatively cool at around 480oC/330oC (above/below the turbo respectively).

So, now I'm wondering if the addition of an oil cooler might be worth considering?

Cheers

Roachie
0
FollowupID: 402148

Follow Up By: Richard Kovac - Tuesday, Jan 17, 2006 at 01:22

Tuesday, Jan 17, 2006 at 01:22
no
0
FollowupID: 402217

Reply By: Exploder - Monday, Jan 16, 2006 at 19:44

Monday, Jan 16, 2006 at 19:44
If it’s Between 92 to 100 that is Fine if it’s going up to around 110 and above regularly when cruising or just driving normally then that is HOT in my book.

I think the factory temp gauge is Doing OK, there is no point in it registering below 50 as that is cold as far as engine Water temp goes.
AnswerID: 148991

Reply By: Member - John - Tuesday, Jan 17, 2006 at 02:02

Tuesday, Jan 17, 2006 at 02:02
Gossy, If it has been hot, sell it NOW....... I had one, go a tad hot, no problems, till I loaded it for a trip away, got about 100k's down the track and blew the head gasket big time. Expensive to fix. Do you self a favour, sell it while it is still OK
John and Jan

Lifetime Member
My Profile  My Position  Send Message

AnswerID: 149073

Reply By: Gossy - Tuesday, Jan 17, 2006 at 11:36

Tuesday, Jan 17, 2006 at 11:36
The total time it has been "hot" is probably only 20 mins (10 mins in Horracks pass and 10 mins on the freeway). As soon as the pressure of climbing was off it cooled straight away.
NATRAD only found 10% blockage of the radiator but the fan was not doing it's job so they fixed that (no oil). They mentioned that during the flush it was one of the cleanest engines they have seen for it age. Mechanically the veh is fine as far as I can tell. Anyway, I've spent too much money on it now to sell and start that process all over again.
AnswerID: 149109

Sponsored Links

Popular Products (13)