[Jackson]

G'day fellas,

Now I am having an issue with my cooling system and it is doing my head in. In my sierra I have a 4k motor, now first of it had a 9 inch thermo on the radiator and it ran to cold on the road, I put a new thermo in and it still ran to cold on the road. I recently took it on the beach and it would overheat unless I could keep it over 30 k's.

So I figured a new bigger fan would help, so I got a spal 11 inch fan and it just fits on the core. I had to mount the radiator a little lower so the fan would miss the bonnet latch, this made the radiator a bit lower then the thermostat housing so I got a bleed screw so I could get all the air out. Now it is running to hot on the road... It heats up when doing 80-90 k's even so I have no idea what is going on.

Anyone got any ideas? It would be appreciated.

Thanks.

Jackson

[stockman]

Do you have the shroud on there?

[Scrawny]

Usually heats up at speed when there's a blockage.

[Jackson]

Was gunna give her a flush tomorrow so I'll see how that goes. Nah haven't got the shroud for it.

[royce]

fans on the front?

thermos dont flow a whole lot of air compared to a radiator whistling through the wind at 80km/hr so the fan makes a big restriction

move it to the back or piss it off altogether

[lump_a_charcoal]

Is the fan spinning the right way?

[MrRocky]

what he said ^^^

[Jackson]

Yeah the fan is on the front mate, I will see in the morning if I have enough room to spin it around.

I hope it is spinning the right way otherwise I am gunna look like a moron.

[zooky08]

put in between the engine and radiator

[paulv]

If it over heats at 80 - 90 Kmh, it's probably time to check coolant flow.

Make sure the thermostat is opening fully at temperature - stick it in boling water and make sure it is opening all the way up.

Back flush the radiator. Back flush the block. - put a garden hose at full pressure into one end of radiator hose, slide an air duster gun in beside it and give it some solid blasts of compressed air.

Make sure the impeller is still on the water pump and the belt is tight.

Make sure the bottom hose hasn't gone soft, inner coil spring corroded away, etc and is not sucking flat.

[Jackson]

Ok flushed the radiator. Radiator flush was clean as.

Plenty of flow across the top of the radiator and bottom hose is not compressable.

Fan is spinning the right way.

Could the fan really be blocking all the air? I don't have a shroud either. Would one help to force the air to go through the rad?

[ajsr]

Jackson wrote:

Ok flushed the radiator. Radiator flush was clean as.

Plenty of flow across the top of the radiator and bottom hose is not compressable.

Fan is spinning the right way.

Could the fan really be blocking all the air? I don't have a shroud either. Would one help to force the air to go through the rad?

mate ive seen cars overheat from having spotlights fitted so yes.
you want a nice straight path for the air to go through the radiator and the fan will slow the air down or spoil it entirely.
as said put the fan behind the rad, of fit an engine fan

[shandy92]

mate as well as everything being said about the fan, if you have time for the car to be off the rd for a day or half a day, take the radiator out and get it flushed professional. costs about $100, i got mine done while mine was overheating and it was 80% blocked.

hope you get it sorted.

[BlueSuzy]

Jackson wrote:

Yeah the fan is on the front mate, I will see in the morning if I have enough room to spin it around.

I hope it is spinning the right way otherwise I am gunna look like a morEon.

[Jackson]

Well a test drive showed that it has gotten better. Now when I sit on 80-90 it seems to be holding its own at around 80 degrees. Though I might take her for a bit of a longer drive tomorrow.

[Jackson]

Well further testing has shown that the problem is still there...

I have flushed it out, appeared to help a little.

Taken the fan off, appeared to help a little.

Lifted the radiator back up, didn't seem to do much.

So I am kinda unsure of where to go from here...

Any pointers?

[JrZook]

Jackson wrote:

Well further testing has shown that the problem is still there...

I have flushed it out, appeared to help a little.

Taken the fan off, appeared to help a little.

Lifted the radiator back up, didn't seem to do much.

So I am kinda unsure of where to go from here...

Any pointers?

Did you get it professionally checked, rodded out and flushed? How old is teh radiator? You are running a thermostat yes?

[Jackson]

Yeah, got a thermostat, it works.

Nah just put some rad flush in it. The radiator is probably 30 year old like the car so instead of spending money on it I would probably just buy a bigger new one.

Do you think it could be plausible that the radiator is to small? I am not sure what this radiator it is out of but it is smaller then what the 4k engine is meant to have by 70 mm wide. When I put it in I thought it may have been a problem but the stock temp gauge said it never got hot when I drove it from Taree to Newy, though it was pissing down rain the whole way that day...

[JrZook]

Jackson wrote:

Yeah, got a thermostat, it works.

Nah just put some rad flush in it. The radiator is probably 30 year old like the car so instead of spending money on it I would probably just buy a bigger new one.

Well then this will most likely be your problem...

[stocker]

Just curious,
1. but are any of the Fins bent on the Radiator???

2. take the Radiator out, and hold it up to the sunlight, if you cant see light protruding right the way through you know its time for a new one.

[Jackson]

The radiator is very sad looking, but I cannot see why it worked to well a few weeks ago and not well enough now...

[stocker]

maybe the small amount of flow through has been disturbed