Today's Message Index:
----------------------
1. 07:43 AM - Engine run on when trying to stop. (Thumper)
2. 08:28 AM - Re: Engine run on when trying to stop. (Richard Girard)
3. 11:25 AM - Re: Re: RotaxEngines 912uls power loss on takeoff (paul)
4. 01:51 PM - Re: Engine run on when trying to stop. (Roger Lee)
5. 06:47 PM - Re: Engine run on when trying to stop. (FLYaDIVE)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Engine run on when trying to stop. |
I am putting this out there mostly for Roger but chime in as needed. Rotax 912ULS
almost 800 hours on engine.
Problem: Engine will continue to run diesel mode when I kill the mag switches when
the engine is hot.
Symptoms: I have tried one mag at a time, adding a little throttle before turning
them off, cooling the engine with a long low power decent, Idle speed is 1800-2000rpm,
changed antifreeze, replaced carb balance crossover tube (found a
hole), changed spark plugs, checked wires for any pulled out of connectors, grounds
are all tight on the top of engine where coils are mounted......
History. No problems last summer. This year the problem started after returning
from Sun-N-Fun but it is not even real hot yet here in W TN. I have been running
a lot of 100LL in the past year as I fly 30-50 hours a month and need fuel
to get home. At first it was intermittent now about 80% of the time. Tried
changing spark plugs, drained fuel and now only have 93 pump gas with alcohol,
did find a hole in the carb balance tube and repaired it, sometimes the only
way to get it to stop is turn off the fuel valve. If it is dieseling I can
advance the throttle and it speeds up. On warm up and run up I do get the proper
120-150 RPM drop when doing a mag check. I did a good mechanical carb balance
by the book before leaving for Sun-N-Fun and then had the carbs vacuum balance
checked by Lockwood when in Florida and they said it could not be any better,
but I was not having the problem then. I did watch the online fuels webinar
and did not always run the engine above 5000 as they recommended on 100LL.
But I do now.
Any help Roger or others can give me I will take. This has to be hard on my engine.
Thanks ahead of time for the help.
Dennis Long
--------
Dennis Long
Oakland TN
2000 Aeroprakt A20 Vista Cruiser
Previously Kolb Mark IIIC, 94 Firestar, 84 Ultrastar.
700+hours since 1/1/2009
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=403863#403863
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Engine run on when trying to stop. |
Dennis, I always recommend doing the cheap things first
1. Check you mag switch grounds. If you have a key switch like a Cessna,
add a dedicated ground. If you can get out the switch easily try grounding
the switches when the engine is in diesel mode IF AND ONLY IF it can be
done safely.
2. If you have toggle switches for your mags, check to make sure they have
not failed internally. Even if you have to replace them to test, you're
looking at $10 for a couple at Rat Shack.
Rick Girard
On Wed, Jul 3, 2013 at 9:42 AM, Thumper <dlong1957@yahoo.com> wrote:
>
> I am putting this out there mostly for Roger but chime in as needed.
> Rotax 912ULS almost 800 hours on engine.
>
> Problem: Engine will continue to run diesel mode when I kill the mag
> switches when the engine is hot.
>
> Symptoms: I have tried one mag at a time, adding a little throttle before
> turning them off, cooling the engine with a long low power decent, Idle
> speed is 1800-2000rpm, changed antifreeze, replaced carb balance crossover
> tube (found a hole), changed spark plugs, checked wires for any pulled out
> of connectors, grounds are all tight on the top of engine where coils are
> mounted......
>
> History. No problems last summer. This year the problem started after
> returning from Sun-N-Fun but it is not even real hot yet here in W TN. I
> have been running a lot of 100LL in the past year as I fly 30-50 hours a
> month and need fuel to get home. At first it was intermittent now about
> 80% of the time. Tried changing spark plugs, drained fuel and now only
> have 93 pump gas with alcohol, did find a hole in the carb balance tube and
> repaired it, sometimes the only way to get it to stop is turn off the fuel
> valve. If it is dieseling I can advance the throttle and it speeds up. On
> warm up and run up I do get the proper 120-150 RPM drop when doing a mag
> check. I did a good mechanical carb balance by the book before leaving for
> Sun-N-Fun and then had the carbs vacuum balance checked by Lockwood when in
> Florida and they said it could not be any better, but I was not having the
> problem then. I did watch the online fuels webinar and did not always run
> the engine above 5000 as!
> they recommended on 100LL. But I do now.
>
> Any help Roger or others can give me I will take. This has to be hard on
> my engine.
>
> Thanks ahead of time for the help.
> Dennis Long
>
> --------
> Dennis Long
> Oakland TN
> 2000 Aeroprakt A20 Vista Cruiser
> Previously Kolb Mark IIIC, 94 Firestar, 84 Ultrastar.
> 700+hours since 1/1/2009
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=403863#403863
>
>
--
Zulu Delta
Mk IIIC
Thanks, Homer GBYM
It isn't necessary to have relatives in Kansas City in order to be unhappy.
- Groucho Marx
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: RotaxEngines 912uls power loss on takeoff |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Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Engine run on when trying to stop. |
This issue can usually be traced back to either a bad or no carb sync or as Rick
pointed out the number one cause of dieseling is a bad wire. It may be attached,
but not very good. It could as Rick pointed out be a bad switch or a bad
wired connection in that link. This is where I would focus my attention first.
--------
Roger Lee
Tucson, Az.
Light Sport Repairman - Maintenance Rated
Rotax Repair Center - Heavy Maint. Rated
Home 520-574-1080 TRY HOME FIRST
Cell 520-349-7056
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=403889#403889
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Engine run on when trying to stop. |
Dennis:
For an engine to run it takes four (4) things:
1 - Fuel
2 - Oxygen
3 - Heat usually in the way of a spark
4 - Correct timing
For an engine to Diesel it takes any one OR more of the following:
1 - Fuel - YES - Most definitely - BUT, we are not talking about too much
fuel or too little fuel - We are saying you must have something to burn for
ANY type of combustion to take place.
2 - Oxygen - YES - Most definitely
3 - HEAT - And not a SPARK! Heat as in a HOT SPOT - A glowing carbon spot
- A glowing BURR such as a bad spark plug thread hanging into the cylinder
- A glowing BURR on the spark plug.
4 - Timing - NO - If the timing was bad you would not have a smooth running
engine and your Mag check would be bad.
My GUESS is go with #3!
Oh! Mag switch? Which make and model Mag Switch do you have? If it is a
Bendix with the START position - There is an AD on that switch and it
should be checked annually.
*Barry*
On Wed, Jul 3, 2013 at 10:42 AM, Thumper <dlong1957@yahoo.com> wrote:
>
> I am putting this out there mostly for Roger but chime in as needed.
> Rotax 912ULS almost 800 hours on engine.
>
> Problem: Engine will continue to run diesel mode when I kill the mag
> switches when the engine is hot.
>
> Symptoms: I have tried one mag at a time, adding a little throttle before
> turning them off, cooling the engine with a long low power decent, Idle
> speed is 1800-2000rpm, changed antifreeze, replaced carb balance crossover
> tube (found a hole), changed spark plugs, checked wires for any pulled out
> of connectors, grounds are all tight on the top of engine where coils are
> mounted......
>
> History. No problems last summer. This year the problem started after
> returning from Sun-N-Fun but it is not even real hot yet here in W TN. I
> have been running a lot of 100LL in the past year as I fly 30-50 hours a
> month and need fuel to get home. At first it was intermittent now about
> 80% of the time. Tried changing spark plugs, drained fuel and now only
> have 93 pump gas with alcohol, did find a hole in the carb balance tube and
> repaired it, sometimes the only way to get it to stop is turn off the fuel
> valve. If it is dieseling I can advance the throttle and it speeds up. On
> warm up and run up I do get the proper 120-150 RPM drop when doing a mag
> check. I did a good mechanical carb balance by the book before leaving for
> Sun-N-Fun and then had the carbs vacuum balance checked by Lockwood when in
> Florida and they said it could not be any better, but I was not having the
> problem then. I did watch the online fuels webinar and did not always run
> the engine above 5000 as!
> they recommended on 100LL. But I do now.
>
> Any help Roger or others can give me I will take. This has to be hard on
> my engine.
>
> Thanks ahead of time for the help.
> Dennis Long
>
> --------
> Dennis Long
> Oakland TN
> 2000 Aeroprakt A20 Vista Cruiser
> Previously Kolb Mark IIIC, 94 Firestar, 84 Ultrastar.
> 700+hours since 1/1/2009
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=403863#403863
>
>
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|