water temp overheat on 582

[Tribal Croc]

Hi Tribal croc, het jy al vir Andre gebel om te hoor wat hy sê?

Ja Andre het vir my 2 nuwe radiator caps gestuur om te toets en my vertel van die grease op die rubbers. Hy se ek moet my temps monitor en as dit nogsteeds so hoog gaan sal hy plan maak en kom kyk

[Graham Mac]

important that you make shure the resistance of the temp sensor is compatible to your water temp instrument.
had the same problem and changed radiators from out of airflow to raptor system then putting venturi air flow plates and eventually changing the sensor for the umptienth time to a calibrated resisistance...bingo temp indicates correctly...
from 85 to 90 deg c now runs at 65 deg c.have to put bands on to increase temp now...
all gone from too hot to a wee bit to cold without radiator band.
I had a engine out because running too hot...especially when your in a long taxi line on the ground waiting to take off without AIRFLOW through radiators.
my two pennys worth.
been there done that,.

[Gompou]

Hi JohnCWE
Before stripping the enjin, go to a radiator (silverton) workshop. Thy have a method of detecting a compression gas leak without stripping anything. First do this test. If there is co2 gasses present in the water, you know you have to dig much deeper.

My 2c

[JohnCWE]

Hi guys, bit of a delay but got there this morning.
On Sunday I put everything together again, this time minus the thermostat, bypass pipe blocked off, everything as it should be.

Ran the engine up, takes a bit longer to get to 80 deg
Stuck the thermometer in the water leaving the engine and that was 81 deg, same as the MGL indicated temp, and the water leaving the radiator was 69 deg.
I then assumed that if I have the 80mph airflow into the radiator the problem should be solved.
Flew this morning, OAT 25 deg,
Water takes longer to get to temp but at 65 deg I took off, the water was at 85 by the time I got to circuit height climbing at 65mph and 650fpm, 5995 rpm.
I reduced power and the water took a long time, like a minute, coming down but on the straight and level it seems to stay at 85 deg.
Did a touch and go and on the ground run it was back to 65 deg, at circuit height at a reduced climb rate and 80mph the temp was 88 deg.
All this after the engine was operating normally at between 65 to 80 deg in the past
My question now is what is there in the engine that could change that would generate more heat than usual.
It now seems that the radiator cannot dissipate the generated heat,
Could the higher ambient be a factor, 25 is not particularly high, it was overcast with no wind,
If the water temp is reduced by 10 deg while passing through the radiator while stationary on the ground, then it should surely be able to dissipate any heat buildup in flight.
What is the danger temperature to the engine being damaged, why is the recommended temp 84 deg max?
What damage can be done to the engine, heat seizing, burnt pistons, etc?
The cap is a .9bar cap on the radiator, anti-freeze is 10% mix
Thanks
John

[Morph]

It is an inverted blue top engine and the engine is above the radiator, actually the radiator is across the center front of the engine, it is mounted up against below the gearbox and is higher than the cylinderhead but lower than the pump, a standard long thin rotax radiator

Hi John,

when you say standard long thin radiator are you talking about the one in the pic below. If that is the case then this radiator is way too small for a 582. These are used for 912, because only the heads are water cooled, hence the small size. Most trike installations I have seen use two small or 1 large radiator. The 912 radiator's cooling area is 122 X 339 mm = 41358sq mm. The dual radiator installation is 109 X 290 X 2 = 63230 sq mm. Most fixed wing, closed cowling installations use VW Golf radiators

when you cut the engine to idle for the decent, and touch and go, the engine will cool quite quickly, hence the seemingly low temps on the ground. If you sat still on the ground and ran the motor at full throttle you would see much higher temps.

[BOATCH]

I have the 2 small radiators and one large radiator on my Skyranger with a 582 and temp stays at 80deg in very hot days.The large radiator is situated behind the motor and have never had any prob.

[Duck Rogers]

This engine performed perfectly well within the temp ranges BEFORE it was overhauled.
Even performed well for 28 hours AFTER the engine overhaul.
Then, suddenly.......... temps skyrocketed!
So, what changed?

I can understand a few degrees hotter after an overhaul with everything being new, tight fitting etc etc, but for 28 hours after to suddenly develop a BIG jump in temp? WTF?
C'mon guys, get your thinking caps on, mine's a bit worn out by now

PS.....just thinking about it now: Is it possible that the radiator could have developed a blockage or something? John, you will need to check the flow rate through the radiator. If I remember correctly, you mentioned something about a modification to the rad. Something about making it bigger, or smaller?

I'm getting hotter now.........I can feel it

[ger koff]

Dear Duck

Have you ensured that there is no air trapped in the block? With some engines there is a procedure that one must follow to get all the air out. This sometimes involves opening an air bleed screw until water comes out etc. Not knowing the engine I can't comment further. Best of luck.

[Duck Rogers]

Dear Duck

Have you ensured that there is no air trapped in the block? With some engines there is a procedure that one must follow to get all the air out. This sometimes involves opening an air bleed screw until water comes out etc. Not knowing the engine I can't comment further. Best of luck.

Yes Sir.......thank you very much. Done that already.