4BD1T Running Temperature

[C H T]

Does any one know what the maximum safe running temperature of a 4BD1T is? I have not been able to find any info in my searches.

Christopher

[Dinty]

G'day All, I don't have any tech/stuff but if you have a std fitted temp instrument like me, mine runs on the 1st white line off cold most days, in extreme temps (outside 40+) it will run on the 2nd white mark and I don't run my A/C either, it will also run up near the 2nd mark when towing a trailer with a Land Rover on it in hilly country, I hope that gives you some idea cheers Dennis:angel:

[Rangier Rover]

Do you mean max Phyro temp. Pre or post turbo?

Tony

[C H T]

Do you mean max Phyro temp. Pre or post turbo?

Tony

Sorry all - I should have been more precise - water temp not pyro temp

Christopher

[87County]

The NA 4BD1 definitely benefits from having a thermostat which is correctly operating.

I presume the turbo would as well, in other words they can run too cold, leading to excessive smoke & less power.

Use the Isuzu part and the "o" ring MUST be replaced if the thermostat is to be replaced.

Dave is your man to seek info from on this

regards - Laurie

[Dinty]

G'day All I understood that you were asking about H2o temp, mines a N/A 3.9, it has the correct thermostat and it works so you draw your own conclusions cheers Dennis:angel:

[rovercare]

Thermostat is 82*, I'd be happy with anywhere up to and includeing 92* with general running temp, your not really going to do any harm until 115-120* when it spits the water out and then kills your motor, but you may notice a problem before then

To cold is not good either, so I'd be hopeing to be within^^^^^that range

[C H T]

Thanks for this Rovercare - mine is maxing out at about 94-95* with aircon on big low gear hills, generally runs 82-90* air on on the highway - 82*thermostat fitted. Used to max out at about 90* before I refitted aircon condenser etc. (EGTs maxing at about 540 post turbo)

Christopher

[Bigbjorn]

You really do need to have a correctly operating thermostat in an Isuzu. If they are running cool you lose performance and use more fuel. Readily available from Isuzu dealers who are miles cheaper than LR dealers.

[isuzurover]

I also have an 82 degree thermostat. Usually it sits dead on 82.

Once when I was climbing a very steep hill near Canberra in 40+ degree heat, it climbed to 99 deg. That was the hottest mine has been - flushed the rad afterwards to make sure it wasn't blocked...

Now I have installed the turbo, the temp will climb as high as 90 deg. when I am working it hard.

[rovercare]

Thanks for this Rovercare - mine is maxing out at about 94-95* with aircon on big low gear hills, generally runs 82-90* air on on the highway - 82*thermostat fitted. Used to max out at about 90* before I refitted aircon condenser etc. (EGTs maxing at about 540 post turbo)

Christopher

Sounds reasonable to me:)

[LRO]

Hi
So if mine runs around 65-75 mostly to 70 does mean i need a new thermostat.

[Bearman]

I would say it it sticking open - yes try a new thermostat

[Blknight.aus]

max op temp is set by the coolant and then the quality of the cooling system...


providing your coolant will handle it for prolonged periods you can run up to about 114 degrees at about that point you are right on the limit of the expansion tank caps pressure limit and you will start steaming, once your steaming your making more heat than the cooling system is dissipating, thats when bad things happen.

Id goto about 95 degrees happily then start nursing till about 100 from 100-105 it would be getting babied just enough for me to get it pulled over safely and take additional cooling aids (up to and including firing a CO2 extinguisher at the radiator with the engine running from about 3 feet away)

[abaddonxi]

So, following this thread and thought I'd better check why my temp gauge isn't gauging anything. I thought it'd just be a loose connection.

Turns out it is, the spade on the back of the temperature probe isn't.

So what bit do I buy?

Simon

[isuzurover]

So, following this thread and thought I'd better check why my temp gauge isn't gauging anything. I thought it'd just be a loose connection.

Turns out it is, the spade on the back of the temperature probe isn't.

So what bit do I buy?

Simon

Buy a VDO guage and sender. Then you will actually have degrees instead of coloured bars ;)

[Blknight.aus]

agreed the vdo ones are good BUT it pays to check them in a pot of boiling water or by whacking a thermometer in the thrmostat filler plug while you run it up to confrim it isnt reading low.

[C H T]

Well all is now apprently revealed! When the airconditioning was installed the auto electrician wired up the auxilliary cooling fan so that it ran backwards - it is controlled by a pressure switch - hence long hills low speed fan comes on and immediately reduces air flow through the radiator by 30-50% temperature rises rapidly - fixed now so hopefully no more temp spikes

CHT