Help: Rotax 582 mod99 cooling system
JPS
problem solution.
Problem description:
1. I exchanged my old Rotax 582 (grey head) with the a new Rotax 582 blue
head.
2. The old engine ran a little hot (65-75ºC) but its temperature never
reached 80ºC.
3. With the new engine, the temperatures easily reach 80ºC and even higher
temperatures.
4. The radiator system hasn't been changed (2 radiators, not Rotax brand).
I believe that the new Rotax 582 mod99 cooling system, which includes a
bypass, is the main reason for the increase of the engine's temperature.
With the bypass, the cooling fluid, even with the thermostat fully open,
doesn't go by 100% to the radiators, therefore the cooling effect is lower.
I could solve the problem changing my radiators, which I must say aren't too
much effective, but I'm thinking of another temporary solution.
Considering that my old Rotax cooling system (without a bypass) worked just
fine, concerning its working temperatures, I'm trying to match the new Rotax
cooling system with the old Rotax one:
Blocking the by-pass and removing the thermostat (Note: I'm not worried
about cold seizure due to high external air temperatures which are about
30ºC)
Do you think this solution is possible? Is there any problem that I'm not
aware of?
Please, let me know your opinion. Thanks!
www.JimWilliamson.net
It sounds like a decent _TEST_. Cold seizure may be an isssue but you're
already aware of that. Bottom line is that it seems you know that you
really should change the rad's...
Jean-Paul Roy
just might as well get them. Seizures are no fun, protecting your engine and
your butts have no price either.
Just a tought
Jean-Paul
"www.JimWilliamson.net" <Use...@JimWilliamson.net> wrote in message
news:40c7d760...@netnews.insightbb.com...
Mark Smith
you got some bad advice about the new system,
the 'thermostat' is really a diverted valve, controlled by temperature,
it has a second cover which seals the bypass at wide open fl9ow to the
radiator,
I would not remove it, or change anything,
you had high temps on the old engine, and a bit higher on a brand new
one, sounds about right to me,,,,
change the radiator system, it is admitedly insufficient,,,,,,,,,
I like the grey heads but would swap for the new blue anytime,,,,,,
--
Mark Smith
Tri-State Kite Sales http://www.trikite.com
1121 N Locust St
Mt Vernon, IN 47620 mailto:ma...@trikite.com
JPS
fl9ow to the radiator"
I'm not sure about that fact.
I believe that the the water circulates regardless if the thermostat is open
or not.
This cooling system is similar to the Rotax 618. In that cooling system the
thermostat didn't seal the bypass at wide open radiator flow.
Can you confirm your point of view?
Thanks!
"Mark Smith" <ma...@trikite.com> wrote in message
news:40C862...@trikite.com...
Mark Smith
seal it tight,
I'm not sure on that point, but the thermostat does have a second flap,
that when the flow to the radiator opens, it closes off the bypass,
doesn't it make sense that having an open flow through a short hose
would 'bypass' most of the flow rather than pump water , I'm sure,
through a much higher pressure drop flow passage/s through the radiator,
there is a flap, there is a machined area that matches the flap, that i
am SURE about,
as to the 'sealing' part, not,,,,,,,,
but it just makes sense,,,,,,,,
you are right, the water flowa all the time, with a proportion through
either the bypass or the radiator, depending on the temps at the
'thermostat',
BTW, it is more of a thermostatically controlled flow diverter in the
618 and the blue head,
all the bigger sno,water engine shave had this system for many
years,,,,,618 being the test bed for the ul market,
i love it on my 500, quick warmups due to no flow through the rad, then
very even temps regardless of performance and power output, at least up
to the capacity of the radiator, then the temsp rise as higher operating
temps are needed to transfer the higher amount of heat,,,,,,,
Tracy
it in order for it to be "aware" of the "current" temp of the fluids ?
In any case, the book says the rad has to be able to do 14 gallons per
minute at full flow.
In the interest of others that read this thread in the future... Heres
something from the web on cooling...
Cooling System
Probably the most problematic part of a Rotax 532/582 engine
installation is the liquid cooling system. Why? Because of the varied
application of the engine. Some engines run in cowls, other in open
air, in some cases the radiator is found six or seven feet from the
engine.
While all of these can contribute to problems with the engine, in the
form of overheating, if certain things are done properly you can just
about get away with anything when mounting a cooling system. One of
the first things is to have a system that allows a flow rate of
fourteen gallons per minute. This simply means that if water were
poured from a container into one end of the rad - fourteen gallons of
fluid should go through the rad in a minute.
The next is to have someway of adjusting the AIR FLOW going through
the radiator. This can be in the form of a set of louvers, or just a
mechanism that adjusts the rad up and down in the airflow, The purpose
of this is to maintain a constant temperature in the cooling system
-especially during the change of seasons. The temperatures you are
looking for are 140 degrees Fahrenheit to 180 degrees, with 160
degrees being the preferred temperature.
Many aircraft I have seen in the field exceed the 180 degree F
temperature, This is not the fault of the engine it is the fault of
the designer.
Other things you should remember are :
Use a water temperature gauge that uses a probe that comes off the top
of the cylinder head, there is a threaded hole for the probe for this
purpose. I have seen some manufacturers use car water temperature
gauges and have the probe come off a "T" in the line. The difference
between the two locations and types of probes can be in excess of 50
degrees difference.
When mixing your anti-freeze to water solution use only DISTILLED
WATER! Some owners have used well water, water from a tap with a water
softener, etc. The block and cylinder head used by Rotax are ALUMINUM,
as soon as any other metal comes in contact with it the aluminum will
start to corrode. In two cases where owners have sent me engines with
overheating problems, I have had to throw the cylinder heads away
because there was so much corrosion in them that the water would not
flow through!
Install a ROTAX thermostat. A thermostat brings the engine up to
operating temperature quicker, and helps maintain it during long
taxiing or long slow approaches. In my mind a thermostat should be
something that every 582 should have.
It is also an item that should be visually checked every four or five
months. Over the years I have seen about a dozen of them that have
failed at solder joints, or have stopped working.
Icrashrc
>it in order for it to be "aware" of the "current" temp of the fluids ?
Generally this is done by way of a small [1/8"] weep hole in the valve part of
the thermostat. Not sure how Rotax does it as i've not seen one of their
setups.
remove my-wife to reply :-)
Mark Smith
>
> Wouldn't the thermostat have to have a little "bypass" engineered into
> it in order for it to be "aware" of the "current" temp of the fluids ?
I've been nice so far but your attitude is getting to me,,,,
the valve has flow through it all the time,
it directs the water where it needs to go based on the temps,
why don't you go get one and study it a bit as i have done,
maybe even draw up a small device that would retrofit to the older grey
heads engiens , as I haev done, to provide the bypass style temp
control,,,,,,,,,
keep reading books and not having the parts in your hands and you will
continue to say some really off the wall stuff,,,,,,,,,,,
BTW, stop lecturing,,,,,,
I'll use any water I care to !!!!!!!
--
Mark Smith
remove your own wife,
the older style thermostats had two small holes drilled to allow a small
flow for a couple reasons, first to bleed the system, the second to
allow the flow the warm the thermostat,,,,,,
the thermo valve under discussion, has the main flow running all the
time, and it all passes over the thermo portion all the time, and is
diverted out the one end to the radiator or the other end to the bypass
hose,
you folks really need to hold one in your hands before making
comments,,,,,,,
Tracy
remaining paragraphs I cut and pasted from an ultralight website, it
was not my "thoughts" : )
I was not aware of any attitude in the posts.
Tracy
> I've been nice so far but your attitude is getting to me,,,,
>
> the valve has flow through it all the time,
>
> it directs the water where it needs to go based on the temps,
>
> why don't you go get one and study it a bit as i have done,
>
> maybe even draw up a small device that would retrofit to the older grey
> heads engiens , as I haev done, to provide the bypass style temp
> control,,,,,,,,,
>
> keep reading books and not having the parts in your hands and you
> will continue to say some really off the wall stuff,,,,,,,,,,,
>
> BTW, stop lecturing,,,,,,
>
> I'll use any water I care to !!!!!!!
I think I figured out the confusion here, many of you may be using
newsgroup servers or other software like OUTLOOK that recieves posts
from this newsgroup as if it is a DIRECT REPLY TO YOU PERSONALLY.
However, many of us do NOT use that type of software option and
therefore do NOT recieve posts as if they are email directed to us
PERSONALLY. Instead we use Google groups and when doing so are posting
to the TOPIC in the GROUP via our web browsers. Of course, when google
forwards this to those in the group it COULD appear to be an email
directed to you personally from the sender which, in my case, was not
the intention, instead, I am posting to the message topic "thread" and
therein all of the readers of the thread including those two years
from now that stumble on the topic.
If Mark was the last poster in the thread then I can see how he might
percieve that I was directing the content to him personally since,
technically, it is the last poster that I am replying to via Google,
however, it is the topic, and not any particular thread participant,
that my content was directed towards.
In any case, it appears that my question was answered, the older style
thermos did have two holes in them which would allow the thermo to
"know" what the current liquid temp is and to respond accordingly.
As for the remainder of my post, which I pointed out was not my
original thought but copied from a website, I assumed that since the
author of this thread was under the impression that his rads might not
be up to snuff then knowing that they must be capable of 14 gal per
minute flow rate might prove helpful in his determination as to the
suitability of his current rads for his particular implementation,
so,I inserted that web content for review/comment by those with
expertise on this engine.
So if I came off as being off the wall, lecturing or posting with an
attitude then I apologise. Except for the first sentence where I ask a
question, the majority of the content of my post was not originally
authored by me but merely copied from an ultralight website, as I had
indicated in the original posting.
Thanks
Google groups UL
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&group=rec.aviation.ultralight
Mark Smith
my comment on the 'attitude' was from you asking several questions which
indicated you had never actually led any opf these parts in your hands,
ie, a 618 head, to see the type flow control they use,
then addign a lecturous long discussion of what to do and not to
do,,,,,,,,
just seemed a bit trollish to ask a fairly good quetsion assuming you
had never seen any of this stuff and then come off as an expert,,,,,,,,
sorry,,,,,,,,,