912ULS Temp in Vegas

HI Nick

go back to the installation manual, IM, for the ULS.  Check the section on cooling and have a read.  There are several things to check for.  Be sure that you are using a good coolant organic acid technology (OAT) or hybrid version of that (HOAT) and please use the premix versions of that as they have the blend exactly where they have be for best performance. 

Be aware of which cylinder heads your engine has, without suffix or with.  The difference is in one case we are talking about cylinder "head" temp and the other is cylinder "coolant" temp.  This is due to the different placement of the sender.

I would as a first step test the pressure of the engine to see if there is any pressure drops.  The most common issue is the coolant cap fails to hold the 1.2 bar fully and this leads to problems with high coolant temps.  

Cheers

Thanks Sean—

I will start with a slower climb out and rerouted my air cooler (radiator)..

flying this week to see if it helps..

 VR

Joe

Hello—

yes I am sensing the same—

re arranged my radiator for better direct airflow—-

will let you know if it helps…

VR

Joe

RW,

"Be sure that you are using a good coolant organic acid technology (OAT) or hybrid version of that (HOAT)" 

Agree 100%

"...use the premix versions of that as they have the blend exactly where they have be for best performance. "

Can't agree - assuming quality/appropriate (as above) fluids used -  mixing your own, to the required specifications (Rotax/concentrate ,manufacturer) gives a degree of certainty that you will not get from a premix.

",...... talking about cylinder "head" temp and the other is cylinder "coolant" temp"

Please expand on this - how will this understanding materially effect the management of the engines cooling?

".....most common issue is the coolant cap fails to hold the 1.2 bar fully and this leads to problems with high coolant temps. "

Not sure how a failed radiator cap fits into the question being asked. A radiator cap failing to hold its rated value, will lead to coolant loss, which in turn will lead to overheating - at this point there has been no mention of coolant loss.

Hello Nick--

Yes lowered my via (Mr. Lee) out of AZ--

Took out all kinks/rounded un necessary alignment of hoses.. Both Oil and Coolant..

Also ensured my Oil cooler was properly aligned with intake to aid in cooling--

My climb out was 252...Now its 238--I live in Vegas so temps are high so for me

a significant improvement--

VR

Joseph Gall