[experament-u2]

my grand vit was overheating on the highway today,
i dont know whats going on
it has new coolant, the thermostat has being cut out (its hot up here in the NT), no bubbles in the coolant that i can see, no white smoke, all new oils i cant work out whats causing it to overheat
its a G16b

if anyone can help and point me in the right direction that would be awesome

[atari4x4]

viscous fan clutch?

put the thermostat back in as the water doesn't spend long enough in the radiator to cool down!

[want33s]

The rad is clogged or the water pump has rusted its fins off and either way there is insufficient water flow.
Could also be the bottom hose sucking flat due to the internal spring rusted away.

[experament-u2]

fans going normal, no blades missing, fan shroud is there and looks like water pump shaft is turning

[experament-u2]

want33s wrote:

The rad is clogged or the water pump has rusted its fins off and either way there is insufficient water flow.
Could also be the bottom hose sucking flat due to the internal spring rusted away.

iv given the radiator a complete flush,
what do you mean mate by bottom hose sucking flat?

could it possibly be a head gasket gone? even without signs of bubble or milky oil or oily coolant?

[want33s]

If the water pump is in good condition it will suck water so hard out of the bottom hose that the hose will try to collapse under vacuum. That's why the manufacturer usually fits a spring inside it. To stop it collapsing on itself and the pump cavitating.

[royce]

also why you have a thermostat to flow the water down

[experament-u2]

i will havto check because i don't recall seeing one when i removed the radiator to flush it out. thanks mate

so if the bottom hose is sucking flat what are the symptoms? other than the obvious, and would it usualy happen during idle or only under load as teh engine pics up?

[atari4x4]

experament-u2 wrote:

fans going normal, no blades missing, fan shroud is there and looks like water pump shaft is turning

The viscous clutch do wear out & get lazy.

To diagnose diagnose a faulty viscous fan hub get the motor up to the higher than normal temperature. At this point the hub should be locked to the motor to trying and bring the temp back down.

With the bonnet up, motor running turn of the engine and watch the fan. If it does not stop with the engine but continues to freely spin the clutch is buggered.

[want33s]

Gus,
the problem is at highway speed so it has nothing to do with the fan OR the viscous clutch as at 100km/h(or thereabouts) there is a lot more airflow through the rad than the fan could ever provide.

[atari4x4]

want33s wrote:

Gus,
the problem is at highway speed so it has nothing to do with the fan OR the viscous clutch as at 100km/h(or thereabouts) there is a lot more airflow through the rad than the fan could ever provide.

oh crap, i didn't even read that part.... i just saw overheating blah, blah, blah

[gman]

atari4x4 wrote:

want33s wrote:

Gus,
the problem is at highway speed so it has nothing to do with the fan OR the viscous clutch as at 100km/h(or thereabouts) there is a lot more airflow through the rad than the fan could ever provide.

oh crap, i didn't even read that part.... i just saw overheating blah, blah, blah

I would still test it thou, I've had a faulty fan clutch create over heating at freeway speeds on a normal summers day and on 30+ days overheat all the time. but like everyone is saying thermostat must be fitted and bottom radiator hoses can get sucked in at high engine rpm eg doing 100kmph water pump vaccum will do this.

[whincup]

so you should be able to see the hose collapsing while revving the vehicle? just curious because my 1.3 has the same overheating problem, only on highways...

[experament-u2]

whincup wrote:

so you should be able to see the hose collapsing while revving the vehicle? just curious because my 1.3 has the same overheating problem, only on highways...

il have a look tomorow at the clutch fan and hose after a morning drive to see if mine is doing anything like that, im also visiting my mechanic mate to see what he makes of it so il post results if we find anything.

quick question mate what condition is your radiator? are the fins bent at all? or filled with mud

[Bucket]

atari4x4 wrote:

experament-u2 wrote:

fans going normal, no blades missing, fan shroud is there and looks like water pump shaft is turning

The viscous clutch do wear out & get lazy.

To diagnose diagnose a faulty viscous fan hub get the motor up to the higher than normal temperature. At this point the hub should be locked to the motor to trying and bring the temp back down.

With the bonnet up, motor running turn of the engine and watch the fan. If it does not stop with the engine but continues to freely spin the clutch is buggered.

OR it could be so worn out that you can feel the freeplay just by holding the fan on either side and shaking it a bit....Yes, mines definatly farked!

[experament-u2]

well i had a chat to a mechanic mate today
and its not a blown head gasket, so we have narrowed the problem down to
the thermostat
radiator
and water pump

i was told EFi engine should have a working thermostat? is there any truth to this? i noticed my cooling problem got a little worst when i pulled out my seized up thermostat.

[atari4x4]

yes all vehicles should have a working thermostat, it controls the operating temperatue.

[Bucket]

Might sound stupid, but have you checked/replaced your radiator cap? I found mine was getting hot and I never checked the cap. Found some of the rubber had worn away and it fixed a bit of my overheating probs.

[steak_knife]

Radiator's blocked.

[experament-u2]

cheers for the info mates
so looks like im up for a new thermostat
(dose anyone know if one for a EFI vit will work? especially the one from suzistore http://www.suzistore.com.au/shopexd.asp?id=454 )

and get my radiator re-cored and then get out wheeling again

[whincup]

...i would think that a blocked radiator would cause overheating at lower speeds, highway speeds still have enough air flowing around it to cool it somewhat... and broken fan same thing... i know recently i pulled out the thermostat and gave it a thorough cleaning and rinsing. didnt make a difference. might replace it this week see how it goes. next will be new radiator...

[banga]

[quote="whincup"]...i would think that a blocked radiator would cause overheating at lower speeds, highway speeds still have enough air flowing around it to cool it somewhat.

not entirely true my vit had a blocked rad after i changed the motor over and it heated up at high way speeds

[Hybrid]

Have you got a repco or autobarn nearby? They will have the right thermostat for you. I think even supercheap could get one in. But if you're out in the sticks just ask your mechanic mate to get you one in. Don't bother with the radiator until you've tried the new thermostat. It's already been identified as a problem so may as well rule it out first. Especially since you mentioned the previous was siezed. Sounds like you haven't had a working thermostat in there for a while. It's the cheapest first option.

[shep]

get ya radiator reamed out mate. $50 in katherine.

[squirezook]

You can buy a few different thermostats for your motor. I don't know what the recommended suzuki one is but I changed mine from 90/95degree to a 75/80degree this allows the coolant to move a bit sooner. Didn't sort out my running hot problems ( running a supercharger) but that is a different tale.

[experament-u2]

cheers everyone for helping me out so far,

Hybrid wrote:

Have you got a repco or autobarn nearby? They will have the right thermostat for you.

i picked up a thermy today for $25 from repco, so hopefully that will do some good

next up is to sort the radiator, il be giving it a test hopefully soon to see if its still heating up.

quick question my bottom hose on the radiator is colder than the the top and heater hoses, is this normal or can it be a sign of a blocked radiator.

[want33s]

experament-u2 wrote:

quick question my bottom hose on the radiator is colder than the the top and heater hoses, is this normal or can it be a sign of a blocked radiator.

Water flows in the top and out the bottom of the radiator... The bottom hose being cooler than the top hose suggests the radiator is doing something towards cooling the water.

[experament-u2]

want33s wrote:

experament-u2 wrote:

quick question my bottom hose on the radiator is colder than the the top and heater hoses, is this normal or can it be a sign of a blocked radiator.

Water flows in the top and out the bottom of the radiator... The bottom hose being cooler than the top hose suggests the radiator is doing something towards cooling the water.

thats good to know it doing its job,

bit of an update, i installed the new thermy today and wow what a difference, so far driving around it stays just bellow halfway feels a heap better.

[atari4x4]

experament-u2 wrote:

want33s wrote:

experament-u2 wrote:

quick question my bottom hose on the radiator is colder than the the top and heater hoses, is this normal or can it be a sign of a blocked radiator.

Water flows in the top and out the bottom of the radiator... The bottom hose being cooler than the top hose suggests the radiator is doing something towards cooling the water.

thats good to know it doing its job,

bit of an update, i installed the new thermy today and wow what a difference, so far driving around it stays just bellow halfway feels a heap better.