BJ70 over heating at altitude

[Northernbeast]

Hello, I have a 1985 BJ70 Diesel that stays at low temperatures at when in town or on the trail. If I am driving at for some distance on the highway or at altitude, the temperature gauge heads to the red. I've checked to cap (new), no leaks in the rad or hoses, any ideas? I have stopped going out to the mountains outside of Vancouver as I do not feel comfortable with this issue.

 

[Kroll]

How's your fan clutch?
Check if it is engaging and it has holding power.

 

[Radd Cruisers]

Radiator, fan clutch or thermostat.


~John

 

[hopper]

I had the same thing on our 85 BJ70. After I had the injectors rebuilt and the rad placed to a four core, no further problems. Cann't say which one did the trick, but 70K later, still running strong.
Regards

 

[Chang-kuao-lo]

get it up to running temperature, and while it's running get a feel of both the upper and lower rad hoses. the lower hose should be about 20 degrees cooler than the upper. if they are both the same, your rad is likely clogged.

 

[Gun Runner 5]

While I wish you luck in correcting your overheating issues I must admit it is refreshing to hear an overheating story that does not involve a 2L-TE. Are you still running the factory water temp. gauge? ..............1978HJ45