Hi Duncan,
We did not have carb ice very often, and as I recall, the carb temp was
always just a few degrees above 0 degC. I am not an expert in this
area, but I believe you are referring to air temp when you say 20C. The
carb temp (at certain throttle settings) associated with icing would be
close to zero due to the venturi effect. We can see the carb temp
change considerably (5+ degC delta, as I recall) as we go from cruise
power to idle, for example. The carb temp gauge we are using is the one
that came with our Skydrive kit, and plugs into the supplied heating
block.
Regards,
Terry Seaver
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Duncan
McFadyean
Sent: Tuesday, September 05, 2006 12:16 PM
Subject: Re: *** SPAM *** RE: Europa-List: Skydrive on/off control
--> <ami@mcfadyean.freeserve.co.uk>
<<When the carb temp came down to a few
degrees (C) above zero, carb ice was a definite possibility.>>
I thought ice was a possibility at any carb temp below 20C?
Have you experienced carb ice at carb body temps much above 0C too?
Duncan McF.
----- Original Message -----
From: "Terry Seaver (terrys)" <terrys@cisco.com>
Sent: Tuesday, September 05, 2006 5:32 PM
Subject: *** SPAM *** RE: Europa-List: Skydrive on/off control
> <terrys@cisco.com>
>
> Hi,
>
> We have a mono-wheel XS with 912S and have had the Skydrive carb
heat
> since first flight, 5 years and 450 hours ago. At first we had the
carb
> heat on all the time, but after a year or so installed the supplied
> water valve because of problems with hot starts in warm weather.
> Installing the valve (and turning off carb heat during the taxi back)
> cured our hot start problem.
> Once we had the valve installed, we were able to carefully measure
> time to climb as a check of any lost performance due to carb heat on
vs
> off. There was no measurable difference in climb performance.
> Also, once we had the ability to fly with carb heat off, we found
> that we could get carb icing, on the ground and in the air, even on
what
> seemed fairly moderate days. When the carb temp came down to a few
> degrees (C) above zero, carb ice was a definite possibility. Turning
on
> the carb heat water cured the rough running in seconds.
> As others have mentioned, we mounted our carb heat water valve on
top
> of the port side foot well, with relatively short water tubing runs to
> the valve, and ran a stiff wire through the firewall for control from
> the cockpit.
>
> Regards,
> Terry Seaver
>
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of Karl
Heindl
> Sent: Sunday, September 03, 2006 4:09 AM
> To: europa-list@matronics.com
> Subject: Re: Europa-List: Skydrive on/off control
>
>
> Tim,
>
> That is what I thought, but it is actually not true.
> When on the ground, and you have a long taxi run, especially on a
grass
> field and/or on a very hot day, the hot coolant will cause the fuel to
> boil in the carburator bowls. You can easily verify this by looking at
> the clear carb vent tube through the stbd cowling door, and you will
see
> the fuel bubbling up into the airbox. You will not be able to start
your
> engine at this stage as the carbs are flooded. I've proven it by
putting
> a clamp on the coolant hose to stop circulation. The local Rotax agent
> educated me about the Skydrive. He also claims that because the added
> collar moves the carburator further from the engine, it contributes to
> vibration problems.
> And lastly, I don't believe that hot air and hot fuel going into the
> combustion, does not affect engine performance. You have a 914, so you
> wouldn't know.
>
> Best regards,
>
> karl
>
>
>>From: "Tim Ward" <ward.t@xtra.co.nz>
>>Reply-To: europa-list@matronics.com
>>To: <europa-list@matronics.com>
>>Subject: Re: Europa-List: Skydrive on/off control
>>Date: Sun, 3 Sep 2006 13:45:58 +1200
>>
>>
>>Karl,
>>Just keep the carb heat on all the time, no performance penalty.
Having
>
>>a switch is just another thing to go wrong and fix!
>>Cheers,
>>Tim
>>Tim Ward
>>12 Waiwetu Street,
>>Fendalton,
>>Christchurch, 8052
>>New Zealand
>>
>>Ph +64 3 3515166
>>Mobile 021 0640221
>>ward.t@xtra.co.nz
>>----- Original Message ----- From: "Karl Heindl" <kheindl@msn.com>
>>To: <europa-list@matronics.com>
>>Sent: Sunday, September 03, 2006 12:20 PM
>>Subject: Europa-List: Skydrive on/off control
>>
>>
>>>
>>>
>>>
>>>Does anyone know of an inline valve, controlled electrically, for
>>>controlling the coolant flow in the Skydrive carb heater ?
>>>I know they exist for central heating systems, but are the wrong
> voltage.
>>>
>>>thanks in advance,
>>>
>>>Karl
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>>
>
>
>
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