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si u may remember me talking about a my car overheating a couple times before. since then i had the radiator recored and things were much better in everyday driving conditions. BUT

a fair few times now once i give the ol girl a thrashing, particularly difficult sandy hill climbs like in the pines, she heats up quicker than a kettle, until the gauge is almost to the red. then the overflow bottle starts steaming n stuff.

weirdly today i did some hill climb attempts then when she got a bit hot i let her idle for like 15 minutes with thermo on etc to cool down. then when i walked back to the car steam was coming out of the overflow and it was boiling like a geyser. wtf!
i want to get to the bottom of this as i can only have a short thrash before she has to cool down for like 15 mins.

EA82T with no heat shields, rad was rodded at start of the year, no coolant leak, no busted head gasket. i cant think of anything causing this heating apart, but possibly something turbo related.
soory for the novel. any suggestions appreciated.

mabye JUST mabye the water pump is on its way out
like mabye the seal is leakin n it isnt allowin it to flow properly

OR even more of a mabye the thermostat isnt openin fully

thermostat seems fine - tested it about 5 months ago but yer. could be water pump on its way out i spose, but car seems to run fine on the road with air going through it.

hnmmm just thought of another thing did u get all the MUD out of the radiator
could be blockin the air flow

nah the water pump shudl be cast iron so it shuld be fine and if the seal is gone then it will be leaking out the weep hole on it.
but one way to check it wuld be to take the belts off then try n wiggle the pulley on it up and down and if its got bearing play then u shuld consider replacing it

and thermostat replacing it now wuld be good insurance either way.

get some beefed up fans aswell lol

his radiator is clean.

just fully take ur thermostat out, mine's been out for yonks...

perhaps try switching your thermo so you can turn it on and off when you want, i had that with the old motor, it was always freezing. There must be a deeper lying problem tho..

hope u sort it out soon dude.

alex

Matatak wrote:nah the water pump shudl be cast iron so it shuld be fine and...........

huh? what are you thinking here ?

ea82t ?, if it hasn't yet had a water pump replacement in its lifetime, then
that is definitely it!
The pumps impeller wears to a point that it just does not push enough water.
And you are describing the exact same problem I had.
Also its true, a standard ea82 radiator is just not up for it, especially in sand or other low speed, hi work terrain.
After that it'll feel like a new engine:)

fredsub wrote:huh? what are you thinking here ?

ea82t ?, if it hasn't yet had a water pump replacement in its lifetime, then
that is definitely it!
The pumps impeller wears to a point that it just does not push enough water.
And you are describing the exact same problem I had.
Also its true, a standard ea82 radiator is just not up for it, especially in sand or other low speed, hi work terrain.
After that it'll feel like a new engine:)

yes but usually the impellers are cast iron so they normally dont wear
and they will only usually wear if coolant isnt replace as scheduled or tap water has been used in the radiatior (dont know if thats a issue with over east but it is in WA coz of the minerals in our water)

but yes maybe the impellers arent cast iron in these ones just most engines i no of they are

it not recommended to remove or use colder thermostats with efi engines coz it may give different performance depending on sensors. Tridon do a high flow thermostat , cost twice as much but worth a try

yer i was talkin 2 my old man (Mechanic ) he reckons it sounds like a radiator issuse like if its non tubro rad n it may need to b the turbo 1

or u could look into puttin a smaller pulley on the water pump to help flow the water through quicker

the water pump isnt drivin off the T/Belt is it
then that wuld be almost impossible to get a smaller pulley for it id think
but if its driven off a drive belt then yer maybe the belt will need to be a shorter one as the existing one may not have enogh adjustment left to accomodate a smaller pulley.

if u hadnt had it done recently id say get the rad serviced but that ideas screwed lol

and then theres the other option of an extra fan on it - wt do ppl think of this idea??

From what you have said, in normal driving it cools adequately, but when given some stick or just sitting still idling it overheats.

I'm not sure, but is the radiator from the normal EA82 motor, or is it from a turbo motor?

Don't have my manual handy, but it may be that the cooling capacity of the n/a radiator isn't up to the heat generated by the turbo motor as it currently works.

Might be an idea to try another thermofan on the radiator to increase the cooling capacity under load or when it is sitting still, or simple as it sounds, to check the thermofan is pushing air the correct way. I am assuming that the thermofan is coming on at the correct temperature?

Perhaps there is a blockage in the motor itself that is preventing the full flow of coolant through the motor, and this only shows itself at high load or when idling.

I had this occur on a Datsun once - got the radiator replaced, but the crap that was floating around the system had made its way into the motor's coolant system, so even though the radiator was brand new, it still overheated because the motor itself was blocked. I had to get it flushed at high pressure to unblock the motor itself, then the temperature improved. Like everything in cars, it is only as strong as the weakest link.

Hope you find the solution soon,

Crundle

Cooling systems .

If the things drivable I always check the obvious things like ignition timing ie also that the dizzy advances/retards properly and that there's no air leaks (lean running) .

There is no way to tell the condition of the water pump impeller without removing it and if your going that far might as well fit a new pump . Using a smaller pulley to overspeed a corrosion damaged impeller achives very little .

Radiator facts . Aluminium radiators RULE . I know everyone loves to quote that copper is a better conductor of heat than aluminium but (there's always a but) most people don't realise that copper core radiators have the gills/fins soldered to the tubes and solder having a high lead content is a very poor conductor . Result , tubes get hot and the solder partially insulates the tubes from the gills so heat transfer is not what it could be . Also copper/brass radiators are MEGA heavy compared to aluminium .

Ally rads have their issues too and the one that urks me most is the composite tanks that many have . The real answer is to have an all aluminium one made meaning welded on aluminium tanks as well . They don't have to be a throw away because the tanks can be cut off and welded to a new core .
So a far better heat exchanger and a much lighter one as well .

Defence no 2 is to use a full flow oil cooler because pulling some of the heat out of the lube oil can make a huge difference .
Working any car hard at low speeds is going to really push its cooling systems because there's just not enough airflow throught the radiator to waste the
extra heat .
If off roading is your goal and you have A/C it may be time to lose it . The condenser core is in front of the rad so it won't be getting the best airflow it can . IMO the EA82/T is no powerhouse and A/C just saps it a bit more . Its only practical value to me is to demist the windscreen . I think I'd rather give the engine every fighting chance to keep its cool and not damage head gaskets so your call on that one .

Cheers A .

Are you absolutely sure the head gaskets are okay? Ie, taken the heads off to inspect?
Have u noticed any extra steam or water vapour comming out of the exhaust...its possible the gaskets have breached near the water channels and coolant is being forced into the cylinders and out the exhaust. It happened on a Sigma I used to have. This would probably only happen during ur "extreeem" driving moments =)

You just fitted big mother of a bullbar yeah? could be impeding airflow through rad. I reckon my car runs cooler when I take the spotties off, but i also agree with Discopots maybe look into a radiator with greater cooling capacity. I have a custom aluminium rad and its the biz

timmo

cheers for the input - all posts will be taken into account

after thinking about some others opinions i have decided to keep the thermostat in as i believe it still works fine. today i bought a 12" eleccy thermo fan (a cheaper one as davies craig ones were thrice the price!). i plan on removing the current clutch fan as it has no shroud and not much help indirected airflow. so ill chuck the other thermo- wire it so its on all the time like the clutch fan, and test her out this weekend with some more 4x4 as she only overheats under these stressful conditions.

i think the head gasket is still good, if it was gone there would be a ****load of steam out the exhaust and temp would be high on the road too.

the bullbar makes no difference as it is about the same weight as my setup before and currently has better airflow as i have no spotties on.

i will check flow direction of the secondary thermo just incase.

If the things drivable I always check the obvious things like ignition timing ie also that the dizzy advances/retards properly and that there's no air leaks (lean running) .

also how would i check these?

subi wrote:after thinking about some others opinions i have decided to keep the thermostat in as i believe it still works fine. today i bought a 12" eleccy thermo fan (a cheaper one as davies craig ones were thrice the price!). i plan on removing the current clutch fan as it has no shroud and not much help indirected airflow. so ill chuck the other thermo- wire it so its on all the time like the clutch fan, and test her out this weekend with some more 4x4 as she only overheats under these stressful conditions.

good choice i reckon
dont forget to keep the nuts on the pulley ur clutch fan runs off and possibly put some washers on them so they will actually hold onto the pulley tightly

and yes i will come for some 4x4ing to at the pines in my wagon if u r gonna go there (dont wanna go to far as i reckon therell be no dash in still)

think you can test water pump without removing. With the EA81 the meatl pipe from the thermostat housing, round the firewall side of carby to heater disconnect this and watch water flow with engine running. Find the ea82 equivalent of this pipe and do same.

if all this seems to be ok the radiator out of the old 1600 suby's does fit with slit modification they have twice the capacity of fluid my dad has 86 touring wagon and it used to over heat all the time then we changed the radiator and now can to like 2 ton of gravel and not even get half gauge

then there is the air con condensor turned radiator trick in addition to radiator that has been tried and suggested in here a few years back