4BD1 Overheating on hills...

[110turboblonde]

I drive a 1994 Land Rover Defender with a 4BD1 Isuzu engine. KLR automotive installed my turbo.
After purchasing my rig, I drove it in mega HEAT from Texas to Montana with no problems.
Two months later -- it suddenly started overheating when going uphill in 4th gear.

I have replaced the thermostat (4BD1 Thermostat - KLR Automotive (https://klrautomotive.com.au/4bd1-thermostat/)).
I have cleaned out my radiator.
I have checked the consistency of my oil and cooling fluid... (not compromised).
I have checked my fan clutch and water pump.

I am considering the following next steps:
-Connect my snorkel to my turbo air intake (maybe this should have been done from the beginning)
-Install an electric fan in addition to my current fan with a switch for hills
-Install an electric fan on the side which will suck out hot air when going up hills
-Purchase a thermometer with a lower temperature rating

Feeling pretty defeated and open to suggestions. Cheers. [smilebigeye]

[V8Ian]

I'd be checking the accuracy of the temperature gauge, before spending money.

[incisor]

Thermostat be the first place to start looking IMHO

[Bazzle218]

Not sure what gearbox your running but holding speed whilst going up hill in 4th will raise the temperature quickly. Before you spend money try changing gear down to third gear and ease up on the power pedal. Also the last thing you should do is connect the snorkel strait to the intake. you need to run it through an air filter . Baz

[Vern]

What radiator is in it?
You say its a 94 defender, so was originally a 300tdi, does it still have a 300tdi radiator?

[ramblingboy42]

what will a thermometer with a lower temperature rating do?

[Gav 110]

What V8Ian says
I’d be using a non contact thermometer to check radiator and engine temps before changing anything else
Maybe new thermostat is faulty??

And as Bazzle218 has mentioned, it’s not a good idea to bypass the air filter

[emoji481][emoji481][emoji481]
Gav

[scarry]

what will a thermometer with a lower temperature rating do?

I think he means thermostat.

Although a lower rating probably won’t help unless the one in it is faulty.

[trout1105]

I drive a 1994 Land Rover Defender with a 4BD1 Isuzu engine. KLR automotive installed my turbo.
After purchasing my rig, I drove it in mega HEAT from Texas to Montana with no problems.
Two months later -- it suddenly started overheating when going uphill in 4th gear.

I have replaced the thermostat (4BD1 Thermostat - KLR Automotive (https://klrautomotive.com.au/4bd1-thermostat/)).
I have cleaned out my radiator.
I have checked the consistency of my oil and cooling fluid... (not compromised).
I have checked my fan clutch and water pump.

I am considering the following next steps:
-Connect my snorkel to my turbo air intake (maybe this should have been done from the beginning)
-Install an electric fan in addition to my current fan with a switch for hills
-Install an electric fan on the side which will suck out hot air when going up hills
-Purchase a thermometer with a lower temperature rating

Feeling pretty defeated and open to suggestions. Cheers. [smilebigeye]

1/ Do NOT bypass the air cleaner.
2/ Are you CERTAIN that the radiator AND the engine block are completey flushed clean and is the radiator still the standard one or was it upgraded to suit the new engine?
3 and 4 installing extra electric fans should not be necessary.

It could be something as simple as a loose/worn fanbelt, worn/corroded water pump or a faulty radiator/expansion tank cap, Check absolutely everything before going overboard with modifications to the cooling system[thumbsupbig]

Are you loosing coolant?

Has the engine frozen recently over winter, IF you are loosing coolant It could be a welch plug problem.