help overheating 2000 jimny

[devsingh]

suzuki jimny
2000 - year of manufacture
120Y 1500 engine and transmission
experiencing overheating when driving ( over 30km/hr) in hot sun

changed :
head gasket
radiator
shroud
fan ( new electric runs direct with relay on ignition)
removed thermostat ( couldn't find a replacement)
replace sensor
installed external gauge and sensor

no bubbles in radiator
changed oil
coolant
no leaks and not loosing water

[Big Z]

water pump

[devsingh]

no water lost and when you remove the radiator cap, you actually see the water flowing , not sure if the flow ie enough or how to test

[timos976]

I am getting a thermal camera soon... Will u allow me to scan the engine for hot spots? Maybe it can help ...

[Big Z]

Start vehicle.
Fast idle the vehicle to about 2500 rpm.
See if both radiator lines get hot. If only the top line is hot, there is a blockage in the system.
Given the age of the engine, the water pump may be worn and no longer as efficient as it once was.

[devsingh]

timos976 sure you can contact me
355 5865

[timos976]

i will call u when it arrive.... but while u wait i recommend BIg z advice...

[devsingh]

replaced water pump, little help but same problem.

[devsingh]

would a 3 core radiator help ?

[timos976]

i hadda get that camera fast

[Big Z]

Your problem seems blockage related as almost everything looks like its been changed.
Possibly a failing cat converter, if still on the vehicle.

[devsingh]

cat taken out by previus owner , even had the exhaust inspected for restrictions of damaged muffler, everything good. i replaced the new aluminium radiator with my two core copper and brass , going for a test run again

[devsingh]

can faulty of leaking spark plug wires, interfere with the temperature gauge ?
i'll test tomorrow with new wires. I believe its some screwed up electrical problem but not sure

[gt4tified]

Its unlikely that both your dash gauge AND an external gauge would go bonkers at the same time, especially if the external gauge is wired independently to its own sensor.

Have you noticed whether the coolant is cycling between the radiator and the overflow bottle? Did you try running the vehicle with the system not pressurized (rad cap half way open) and see if the problem persisted?

[devsingh]

coolant bottle level remains constant, i never let the gauge go above 75%
will try to leave the cap half way open ( not sure what is supposed to happen though)
remember the car only overheats actually running over 4000 rpm

[gt4tified]

Your coolant bottle level is not supposed to remain constant per say. When the engine is hot the level should fall a bit and as the engine is switched off and cooling, it should fill back to the "full" level.

Also, what do you mean by you never let the gauge go above 75%? What does 75% equate to in degrees (C/F)? Didn't you say that you installed an aftermarket gauge?

[devsingh]

i installed a sensor/gauge combo on the top of the radiator close to the top hose. today the temperature went to 220 F so i switched off ac and allowed it to cool

just another thought , the electric fan for the radiator is about one inch from the engine pulleys, would that any contribution to the heating problem ?

[gt4tified]

How is your fan configured, as a pusher or puller? If its mounted on the inside of the radiator, i.e. between the rad and the engine it should be a puller.

[devsingh]

posting pics shortly

[devsingh]

ac fan pulls
radiator fan pulls

[devsingh]

the temperature rises but also drops quickly...

[gt4tified]

Are you absolutely sure you burped the system properly? Just asking eh. Where you located?

[devsingh]

arouca, what you mean burp system ?
feel free to gimme a call 355 5865

[gabriel_tintman]

what i believe gti's talking about is getting air out the cooling system by running it for about 15min without the cap on..

[devsingh]

ohh did that, still no change, i'm going to try having the distributor cap looked at

[DatManiac]

You using the original 1500 carb? Cuz i had a problem with runnin the 1200 carb on my 1500 and it was apparently runnin lean causin my temp to go up with the a.c. on. If not clean your jets in your carb. Also make sure ignition timing is good too.

[devsingh]

original 1500 carb, but i had the distributor retarded a bit, just incase the ignition timing was off; going for a test run now

[gabriel_tintman]

my father explained to me that timing is everything so if your timing is off or distributer is too retarded or if its too advanced you'll get that overheat problem, you gotta get it just right..

[devsingh]

timing checked out to be good, problem still there but not temperature rising not as quickly, going to try changing the distributor to an electronic

[Big Z]

Just thought of this.. exhaust restriction.. is there a catalytic converter installed?
A plugged exhaust causes overheating as well.
An easy test would be using a vacuum gauge to check the engine vacuum at a constant medium rpm.
Low vacuum = exhaust restriction.