Lowell:
I'm not sure but I think it is on the two stroke Rotax engines that the heat
sink compound is recommended. A Couple of reasons could be:
Two stroke engines have twice as many pulses per minute as a four stroke for
the same rpm so probably develop more heat on the heads and the heads being
aluminium may be able to deform easier than steel or iron heads. To help
avoid any deformation the heat sink compound may be advisable. However the
582 is liquid cooled so shouldn't need the extra protection of heat sink
compound.
The heads of the 582 are, I believe, aluminium and if this is the case it
may be an attempt to protect the threads from dissimilar metal corrosion.
As for anti seize compound; most of them use graphite as the lubricator..
this is ok if you are putting a steel or cadmium plated plug into a steel
head but carbon should in any form should not be used on aluminium.
When I was training we would not even mark sheet aluminium with a standard
lead pencil because it would eventually cause corrosion of the sheet.
Noel
-----Original Message-----
From: owner-kitfox-list-server@matronics.com
[mailto:owner-kitfox-list-server@matronics.com] On Behalf Of Lowell Fitt
Sent: Monday, November 16, 2009 11:58 AM
To: kitfox-list@matronics.com
Subject: Re: Rotax spark plugs
I have a question.
What is it about the Rotax technology that it requires proprietary heat
transfer compound on the spark plugs. Is it something like only using
genuine Rotax oil filters? Or genuine GM parts on my car? Or the factory
recommendation that my wife's car only run on name brand gas? - we discuss
this pretty often.
I am a born skeptic, I guess, but intelligent enough to understand an
explanation. if there is one. I ran my old 912 using graphited antisieze on
the plugs, but of course, this began long before Rotax began conducting -
and charging for, I might add - their maintenance seminars.
Can someone give a real rason other than Rotax recommends it?
Lowell
----- Original Message -----
From: <Catz631@aol.com>
To: <kitfox-list@matronics.com>
Sent: Monday, November 16, 2009 4:50 AM
Subject: Re: Rotax spark plugs
> Roger is correct,the silicone paste used on the plugs is not the same
> formulation as the common silicone grease you find in hardware
> stores,Radio Shack
> etc.This information came from Lockwood as I addressed it specifically in
> Rotax engine class. I too have a "truck load" of the standard stuff but
> was
> told not to use it.
> You use very little of the heat transfer compound on each plug. I have
> done two spark plug changes and still have plenty left out of that little
> packet. As mentioned the stuff is available at Lockwood,Leading Edge,CPS
> and I am
> sure other Rotax dealers.
> Dick Maddux
> Fox 4
> 912 UL
> Milton,Fl
>
