Tony
I did not miss the Europa; I had fungi in my lungs and an aging head. I have
returned to attacking the fungi and I bought a book about stimulating the
mind while I was at Kennedy Space Centre; so things are looking good.
JR
----- Original Message -----
From: "Tony Renshaw" <tonyrenshaw268@gmail.com>
Sent: Sunday, July 11, 2010 3:56 PM
Subject: Re: Europa-List: Cooling issues, once again!
>
> Hey bob,
> Glad to hear you r home. How was
> The trip? Did u miss the Europa?
> Reg
> TR
>
> On 10/07/2010, at 6:08 PM, "JR Gowing" <jrgowing@bigpond.net.au> wrote:
>
>>
>> Frans
>>
>> Just back from holiday in US and seen your list of problems.
>>
>> Have you seen the Tropical Chin Intake?
>>
>> I have just fitted one to my 912S installation, still a long way from
>> flying.
>>
>> It forms a sharp edged entry to the large rectangular inlet with a much
>> smaller eliptical entry formed from aluminium.
>> I think I downloaded it from the Europa Club but Popular Flying Assn
>> mentioned at the top of page 1.
>>
>> Frustration is a killer!
>> Best Wishes
>> JR Gowing Kit 327 in Oz
>>
>> ----- Original Message ----- From: "JEFF ROBERTS" <Jeff@rmmm.net>
>> To: <europa-list@matronics.com>
>> Sent: Sunday, June 06, 2010 3:52 AM
>> Subject: Re: Europa-List: Cooling issues, once again!
>>
>>
>>>
>>> Frans,
>>> I have the 912 set up so I might not know what I'l talking about but...
>>> I had the very same issues for the first 150 hours. Every time it got
>>> hot I was in trouble with temps at their limit. I made the shroud for
>>> over the cylinders. I lowered the oil radiator 2 inches behind the
>>> water, I sealed everything, I made new inlets in the upper cowl, and
>>> still didn't get it solved completely. I then finally lowered the
>>> metal duct down an inch or so, so the bottom radiator reached the
>>> lower cowl without the sealant and bam. My temps dropped 30 to 40
>>> degrees. I believe two things helped in this. The radiators we're
>>> getting more air but the big thing was by lowering the duct it opened
>>> the bottom for escaping air. Not sure if this all applies to you but
>>> if you have the duct up to high close to the muff all you need to do
>>> is lower it. You'l be needing to ad a flap in colder days to get
>>> things in the proper temp range.
>>> By the way the shroud did even the cylinder temps out but it didn't do
>>> much to cool the water or oil.
>>>
>>> Jeff R. N128LJ Gold Rush
>>>
>>>
>>>
>>>
>>> On Jun 5, 2010, at 5:28 AM, Frans Veldman wrote:
>>>
>>>> <frans@privatepilots.nl
>>>> >
>>>>
>>>> Gentlemen,
>>>>
>>>> Although my initial cooling issues have been improved upon, I'm not
>>>> satisfied at all with the cooling of my 914.
>>>>
>>>> Now, with increasing ambient temperatures, I have to severely limit my
>>>> climb outs. Cruising is ok. During climb, both the water temperature
>>>> and
>>>> oil temperature approach the red line, more or less at the same time.
>>>> Water temperature recovers faster than the oil temperature after I
>>>> power
>>>> down. At this time I can barely make it to circuit height and then
>>>> have
>>>> to level off, build more speed, and then limit my climb with 200 ft/
>>>> min
>>>> until I'm in cooler air. The engine has now 32 hours on it, so it
>>>> might
>>>> still improve somewhat further, but I don't expect miracles from that.
>>>>
>>>> I had to do something.
>>>> First I made an additional exit in the cowling, under the turbo,
>>>> hoping
>>>> to provide more airflow. Whether the airflow in the cowling improved I
>>>> don't know, but it had zero effect on the water and oil temperatures.
>>>>
>>>> Temperatures inside the cowling seem to be ok anyway, no discoloured
>>>> spark plug indicator labels (still bright yellow), no melted tie-
>>>> wraps, etc.
>>>>
>>>> My conclusion was that the problem is not in cooling of the cowling,
>>>> but
>>>> somewhere in the efficiency of the radiators.
>>>>
>>>> So then I built a new radiator inlet, somewhat larger than previous
>>>> one,
>>>> with a lip to avoid digesting the boundary layer and making sure the
>>>> inlet receives ram air, angled straight into the airflow, and with a
>>>> diffuser for which I copied a profile out of a famous book.
>>>>
>>>> It was no improvement over my "free style" sleeker inlet and diffuser.
>>>> None. Very frustrating, as I ruined my nicely shaped and painted
>>>> original inlet for this.
>>>>
>>>> I need to do something, but to avoid ruining again something in
>>>> order to
>>>> solve this problem, I need to hear some experiences:
>>>>
>>>> 1) A shroud over the cylinders. I don't have it, but instead I have
>>>> two
>>>> naca ducts in the upper cowling, curved down to release air aimed at
>>>> the
>>>> cylinders.
>>>> Has anyone ever tried whether the Rotax shroud (or home made shroud)
>>>> makes any difference? Sure, it will cool the cylinders, but does it
>>>> have
>>>> any effect over the water temperature and/or oil temperature? Or is
>>>> this
>>>> again going to be a loss in time and effort?
>>>>
>>>> 2) In my setup the oil cooler receives exit air from the water
>>>> cooler. I
>>>> know there is a "trick" mentioned in the build manual for hot climates
>>>> to lower the oil radiator 2 inches to receive cold air instead of warm
>>>> air, but I didn't opt for this as I don't consider our climate as
>>>> extremely warm, and in winter the oild could actually get too cold.
>>>> Has anyone tried both options, and did it make much difference? Also,
>>>> did it have any influence over the water temperature? Relocating the
>>>> oil
>>>> radiator will be a large project, and I fear that after that I will
>>>> still have to limit my climb outs to avoid the water from boiling.
>>>>
>>>> Yesterday on the airfield I took a closer look at the Rotax 914
>>>> equipped
>>>> Dimona, which is used by the glider club to tow all day long gliders,
>>>> with full power at 50 knots, in all ambient temperatures. They never
>>>> have cooling problems.
>>>>
>>>> What I saw was shocking. The water radiator is fully exposed to the
>>>> airstream, no diffuser whatsoever, it is just part of the cowling,
>>>> as if
>>>> someone took out some skin of the cowling and fitted the radiator in
>>>> the
>>>> resulting hole. The oil radiator is mounted in an angle behind a naca
>>>> duct (I was taught that a naca duct does not provide ram air and
>>>> shouldn't be used for cooling a radiator?). Both radiators just dump
>>>> the
>>>> warm air inside the cowling! It can't be easier than that.
>>>> Then, at the bottom, the Dimona has a cowl flap which just opens the
>>>> cowling to dump *all* air overboard. If it is closed, all radiators,
>>>> as
>>>> well as all cowling ventilation, is blocked.
>>>> How can this system, which looks less sophisticated than our system,
>>>> while violating all rules and knowledge, work so well?
>>>>
>>>> Anyway. At the moment I'm grounded, can't fly like this, and after
>>>> spending a week trying to improve things with zero effect, I'm out of
>>>> options and I'm inclined to leave the airplane in the hangar and find
>>>> another hobby. :-(
>>>>
>>>> Seriously, what should I do?
>>>>
>>>> Frans
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>> --------------------------------------------------------------------------------
>>
>>
>>
>> Checked by AVG - www.avg.com
>> 18:35:00
>>
>>
>> --
>> We are a community of 7 million users fighting spam.
>>
>> The Professional version does not have this message
>>
>>
>>
>>
>>
>>
>
>
--------------------------------------------------------------------------------
Checked by AVG - www.avg.com
19:59:00
--
We are a community of 7 million users fighting spam.
The Professional version does not have this message
|