cooling rotax ignition modules

[BrendAn]

i have read that rotax ign modules run fairly hot which shortens their lifespan.

so on my lsa there just happens to be an unused air intake from when it had a kfm.  i have run a 2 inch hose with flattened end to point at the 

ignition modules so they will be fed cool air when flying.  

is this a good idea or pointless.

[Old Koreelah]

Good idea, but a hose that wide is probably overkill. I use a 25mm hose to duct air to each coil. The flow is probably reduced by a few curves and the friction inside that small scat hose, but it should be enough.
 

Does your big coil cooling air supply affect air flow to the hot bits of the engine?

[skippydiesel]

You can get an aftermarket ignition system, that has long leads, allowing the modules to be located away from engine heat & vibration.

[BrendAn]

15 minutes ago, Old Koreelah said:

Good idea, but a hose that wide is probably overkill. I use a 25mm hose to duct air to each coil. The flow is probably reduced by a few curves and the friction inside that small scat hose, but it should be enough.
 

Does your big coil cooling air supply affect air flow to the hot bits of the engine?

its behind the engine so it should have no effect. the intake is 2 inch thats the reason its that size. it was the engine intake scoop when it was kfm powered.

[BrendAn]

Just now, skippydiesel said:

You can get an aftermarket ignition system, that has long leads, allowing the modules to be located away from engine heat & vibration.

they are on the firewall , well away from engine and exhaust.  the intake was there so i thought i would use it.

[RFguy]

I think many of the problems come from seeing the two modules stacked on top of each other. They cook each other .. 10mm of separation  would do it.... 

but airflow is king !

Edited December 7, 2022 by RFguy

[facthunter]

Blast tubes are commonly used for such cooling in many GA engine installations. Heat will wreck electricals (Except ovens and toasters etc). Nev

[skellywelly]

On 07/12/2022 at 10:16 AM, BrendAn said:

its behind the engine so it should have no effect. the intake is 2 inch thats the reason its that size. it was the engine intake scoop when it was kfm powered.

Hi, do you still have the KFM engine ?

Cheers.

Skel.

[BrendAn]

59 minutes ago, skellywelly said:

Hi, do you still have the KFM engine ?

Cheers.

Skel.

No . The kfm was removed about 25 years before I got the aircraft. Sorry.