Thread: Cooling System Sanity Check

uhhh guys..

its a perentie.. for the major service

is the top radiator hose hot, is the return from the radiator cold?

heres how you field test the cooling system.

blanket the radiator.

warm the engine up,

top hose hot, bottom hose a little cooler, temp gauge normal? heater working?

good. go drive it leave the blanket in place turn the heater fan off leave it set for hot air.

temperature gauge rising after about 5 minutes of driving? good.

turn the heater fan on flat out pull over remove the blanket, drive off. temp gauge coming down?

cooling system checked.

for the alt major service, replace the thermostat and pull and flush the radiator/rod it after you do a chemical flush of the system. Replace hoses as requried.

done.

Originally Posted by Chris078

I can! This is the VDO number that the Land Rover guy gave me

It's 6685-66-095-8448 - for the temp sender

This doesn't seem to be a VDO number?

Originally Posted by cummo

Picked up a new VDO temperature sender from the local instrumentation shop today.
VDO P/N 320.002; 40-120 degree range, 1/8-27NPT thread, 1/2" AF hex, pin connection. $15 all up. Didn't have my original with me, but based on the stamping so on the hex flats the parts guy is 99.9% certain it's the goods.
For the small dollars involved worth replacing just to benchmark it.

This is good info, if it turns out to be correct.

I'll be installing the VDO 320.002 sender on Saturday so fingers x'd it'll fit OK. The temp range is right, hex size right and has the correct pin connector. The probe length is the only unknown. If the probe length the is the same and the NPT thread correct then all should be good. I'll post up how it turns out.

Cheers, Dave

You should be fine Cummo.
I picked up mine from Land Rover today
It's got a LR sticker on it with AYG9603 and 668566-095-8448 on it.

It's in a VDO branded package with 320.002 on the packaging. Reckon you're on the money.

Imgur: The most awesome images on the Internet

excuse the terrible photos, my camera has pretty much died and that's the best picture it will take.

Went for the first run since putting the cooling system back together. New Isuzu 82-degree thermostat installed with jiggle/air bleed valve installed towards housing outlet, new VDO sender, radiator removed, flushed & pressure tested with top marks from the radiator guy. Block flushed up and down with air/water pressure gun, (clean as a whistle), 2 fills and dumps with distilled water, final fill with Nulon L/L coolant.

Warms up and stays relatively stable at what I interpret to be about 95 degrees. Hot water flow from the block via the thermostat seems to happen at about 90 a 92 on the gauge. Markedly different from the old arrangement where the gauge showed a pretty constant 80-degrees.

Logic tells me there should be no issues what with everything flushed and/or new. I'm thinking maybe the gauge earth; I do get a flicker on all gauges with the blinkers operating, but I thought that was normal anyway.
Maybe this is the new order of things and it is OK to run at this temperature. As usual all thoughts/suggestions appreciated.
Cheers, Dave

Few degrees higher than mine (normally around 87-88c or so) probably variances in the gauges rather than anything else.
at least it's more accurate than what it was.

Check the earth lead from the alternator and starter. The earth for most of the electrical system is ..... rudimentary at best in this car. It's a 4 gauge line from the starter back to the harness behind the fuse box and all the earths are simply soldered to that 4 gauge line.
<edit> the power to the system is much the same!

if you pull the cluster, it would be pretty easy to run a line from the battery to the cluster (you will be able to see that the earth wire there is shared between the gauges via a single post, just attach your additional line to that) to test.

I've been meaning to do the same thing for ages, maybe next weekend.
Seeing as I can't drive until I get this drivers seat fixed.

Originally Posted by cummo

Warms up and stays relatively stable at what I interpret to be about 95 degrees. Hot water flow from the block via the thermostat seems to happen at about 90 a 92 on the gauge. Markedly different from the old arrangement where the gauge showed a pretty constant 80-degrees.

Seems warm, mine sits exactly on 82 under normal circumstances.

Hi Chris. As my lack of electrics is legendary, I assume you mean run a temporary lead from the negative battery terminal direct to the common gauge earth in order to bypass the existing body earth? This in my mind (which is a dim place) may then show whether existing gauge earth is the problem. Hopefully I've interpreted you correctly. Dave