Vr 5l caprice overheating

[cartwright]

Hey

Just want some help, My VR Caprice is overheating within 5 minutes of driving it, it pretty much goes to boiling point on the temp gauge. The coolant was a browny colour, so i flushed out the old coolant and flushed out the radiator and put in new coolant, I didnt bleed the system coz idont know how to, I then checked the thermostat and found there wasnt one there so i bought a new one, installed it. I then took it for a drive an it was still overheating very quickly, the dude i bought it off told me the electric fan doesnt work but not to sure if thats the problem. Could it maybe need a new radiator as this one might be blocked, maybe a water pump or maybe a blown head gasket?

Cheers.

[VrWagz1]

Elec fan?? Only if its been modded properly, a few have done here. Minimum twin 12" thermos. If you still have to old clutch fan, re-install it. Sounds like its your problem
But given what your coolant looked like, the radiator could be blocked too!!

[justbad4you]

give the radiator

Hey
a good flush as well...then blled all the iar out of the sys and see how you go
Just want some help, My VR Caprice is overheating within 5 minutes of driving it, it pretty much goes to boiling point on the temp gauge. The coolant was a browny colour, so i flushed out the old coolant and flushed out the radiator and put in new coolant, I didnt bleed the system coz idont know how to, I then checked the thermostat and found there wasnt one there so i bought a new one, installed it. I then took it for a drive an it was still overheating very quickly, the dude i bought it off told me the electric fan doesnt work but not to sure if thats the problem. Could it maybe need a new radiator as this one might be blocked, maybe a water pump or maybe a blown head gasket?

Cheers.

[BlackVXGTS]

The EFI 5l engines use an engine driven thermostatic fan as standard. If your car overheats that quickly from cold then the engine is not being cooled effectively. Assuming you still have the standard fan, the things you could look at are:
1. Fan thermostatic clutch unit not working properly. The fluid within the clutch unit is designed to almost freewheel the fan when the engine is cold and then stiffen up giving maximum fan speed and hence cooling as the engine gets hot. If it's working properly you should be able to hear the fan noise increase to a "roar" as the engine heats up and the fan increases in speed, and the "roar" diminish in volume as the engine is cooled. If this is the problem replace the clutch unit - you don't need to buy the fan part as well.
2. Water pump not working properly - replace water pump - cheap to buy (less than $80 for a good one) and reasonably easy to install - make sure the engine is cold.
3. Blocked radiator - take it to a radiator specialist and get it cleaned or buy a new one.

Bleeding is not an issue with the EFI V8s as they automatically get rid of any trapped air over a couple of days - just keep the fluid in the overflow reservoir topped up.

[VR38]

My radiator was pretty blocked and system needed flushing three times to get the gunk out, i twice flushed it with nulon and the old radiator then once with straight water and the new radiator with a baby sock in the top hose to collect any remaining bits as the inherent design of the radiator filling at the top on the inlet side and exiting to opposite side makes the radiator a big filter and hard to flush without removing it from the car, they do block easily with time.
Don't forget to do your heater too, alot of gunk collects here and will sit in the bottom of the inlet tank of a new radiator if flushed that way.
Once I was confident the system was clear (no discolour in the water) I fitted the thermostate and coolant.

FYI if the radiator has been in service a while it may look good in the car but you may find the road side of the core corroded when you remove it to have it cleaned, best way out is a new one.

[cartwright]

Thanks guys, gonna look to get a new radiator and water pump and see if that helps

[VR38]

First few times I ran the motor with the nulon flushing in it without the thermostat and back flushed it without it too, last time i ran it without the thermostat but with a kid sock in the top hose on the radiator, after i checked for leaks I removed the sock, installed the thermostat and coolant.

Don't forget to test the heater tap (off the car, close it and try blow thru it) and also on the opposite side of the motor where the heater hose has a joiner, that joiner deteriorates, falls apart, causing leaks and blockages. While you have these tow apart flush out the heater.

[cartwright]

thanks mate i will check that out aswell

[VR38]

Did you win?