[JS5D]

My resurrection of my 1984 'barn find' original import Range Rover is progressing well. Driving around to test and fix little issues as they come up.

A not so little issue is that engine seems to lack cooling as it slowly but surely overheats. My Holley Sniper EFI system provides very accurate temperature measurement. I am watching it so never overheated as in boiled, but driving to work (abt 25 miles/30-45min) I notice the temperature is going from 180 to 190 to 200 to 219 at which point I switched off the AC and put on the heating to see it go down to 215. Outside it about 80-90F so this will need to be solved.

I have dual 90W electric fans switching on at 185 and 195 but the original radiator. I recently replaced the cooling water pump as the old one was leaking and the system is brimmed with premix green antifreeze no airlocks as far as I can tell. Driving freeway is actually resulting in higher temperatures (220) then standing in traffic (210), so the fans are working but the radiator just cannot shed the heat that the engine is putting out. The timing is set right and engine is running well.

The exact 1984 radiator is not available in the US, so I ordered a 3 row aluminum 1987-1995 replacement radiator which will require slight modifications to fit. Should take a few hours to fit.

I know these cars have an overheat issue. Is there something else I am missing? Enclosed picture of inside of the radiator (cold side), which does not seem to be blocked but obviously not quite in perfect state. I did rinse it out two weeks ago when I changed the pump and it looks a little better now.


Edit: and I checked and replaced the thermostat, currently a 87C unit. Fully open at about 95C (203F)

 

[95classiclwb]

thermostat replacement is a good idea, other wise you're covering your bases. air fuel mix will cause heat concerns specially if running lean.
I'm almost certain the 84 did not have catalytic converters but just in case it does make sure they are not melted thus restricting airflow, internal rotting of the muffler(s) will restrict airflow as well.
an engine is basically a self powered air pump, it's longevity and continued performance is based on how good it breathes.

 

[portofino88]

Please update after the radiator is replaced, I'm replacing the rad on my 88 and I'm looking hard at the aluminum rads lately.

 

[captainvector]

Another vote for an update after the new radiator is installed. I had overheating issues in a '93 that were only resolved after I replaced the radiator -- and that was after I'd done pretty much everything else (t-stat, water pump, fan clutch, etc) first. If at all possible, don't overheat this engine - bad (read: expensive) things happen!

 

[JS5D]

Ok so changed the radiator and seems to be well. Went for a drive (Houston is getting pretty warm) took some freeway and the temperature never went over 191, little below half on the dash gauge.

Since I am sinking a little too much money into this car I decided to go for an affordable 3 row aluminium 87-94 RRC radiator. My 84 has a different radiator mount but they are hard to get in the US and even in the UK they are about $1000 with very few purchase options. The radiator was only $200 free shipping so I just went ahead knowing the radiator was the correct physical size. I could have gone for 4 row ($270) but that is a fair bit thicker and my electric fans are already clashing with the original (removed) engine fan shaft. The electric fans are driven through my Holley Sniper EFI (throttle body injection)


The new radiator was a fair bit taller but fits. The bottom mount is different with pins slotting into the crossmember, my original radiator has 2 side mounts each side. I transferred the fans which was quite easy.

I fitted it with some custom brackets. I had to move the AC condenser as the pipes were clashing which was a bit of a hassle. I also painted all the exposed steelwork in the car before fitting.


I had originally planned to overhaul the original radiator, but instead just cleaned it with a mild radiator flush. As I removed it I noticed it started weeping coolant, so I think after 30-odd years it was really on it's last legs.

 

[aussiebushman]

It certainly looks as though the radiator was the cause of the problem, but all of the overheating problems I have experienced on 3 of my 8 Range Rovers has been caused by a failed fan viscous coupling and after-market ones can rarely be trusted. If you have further problems. start there!

 

[JS5D]

When I did my research on radiators, either overhaul or renew and with what, I found that there is a lot of information on rebuilding copper radiators, but in fact very few companies are still doing it. I did not find one in Houston and go recommended a small shop a bit out of town. The overhaul cost was quite high and uncertain. To replace you either look at original copper which is basically now a more specialist supplier, or modern Aluminum which seems to be made in vast numbers for any application and quite cheaply.

There are discussions about the cooling effectiveness of copper over aluminium which for various reasons if more-or-less the same. The life span of radiators is in fact a little better for aluminium (assuming you keep your coolant fresh) but expected to be around 10 years (only). I think my old copper radiator was loosing effectiveness not through blockage, but the fins had become very loose from the channels and the whole heat conductivity had deteriorated. Now when the the fan kicks in the air blowing out is so hot it burns your hands, while in the past it was just warm.

I have electric fans (PO upgrade) which I now integrated into my aftermarket EFI system which also has AC compressor input so the fans are kicking in and out as needed.

Obviously the engine is now rock steady at 190F at highway speeds, idle in traffic with ac on etc all of this in 97F Houston heat. Fantastic!

 

[portofino88]

Thanks for the update! Looks like I'll go for an aluminum then. Thanks for the pics too, Lets me know what I'm getting into!