Today's Message Index:
----------------------
1. 03:56 PM - Re: 912 80hp violent vibration on cold start (michaelrosenberg)
2. 05:47 PM - Re: 912 80hp violent vibration on cold start (Roger Lee)
3. 06:17 PM - Re: 912 80hp violent vibration on cold start (michaelrosenberg)
4. 06:54 PM - Re: Re: 912 80hp violent vibration on cold start (Dave)
5. 07:09 PM - Re: Re: 912 80hp violent vibration on cold start (Richard Girard)
6. 07:31 PM - Re: 912 80hp violent vibration on cold start (michaelrosenberg)
7. 08:05 PM - Re: Re: 912 80hp violent vibration on cold start (Pete Christensen)
8. 09:05 PM - Re: Re: 912 80hp violent vibration on cold start (Paul Kuntz)
9. 09:10 PM - Re: Re: 912 80hp violent vibration on cold start (Paul Kuntz)
10. 09:20 PM - Re: Re: 912 80hp violent vibration on cold start (Lowell Fitt)
11. 10:19 PM - Re: Re: 912 80hp violent vibration on cold start (John Hauck)
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: | Re: 912 80hp violent vibration on cold start |
Hi guys, I know this thread was from a while ago, however did you ever find the
solution Froghair. This is the only post I have found with identical problems
to mine. It is only on cold start.... However, I am from South Australia and
a cold day is in the order of 60F. Hardly cold enough to warrant preheating the
engine.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=446415#446415
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: 912 80hp violent vibration on cold start |
Most of the time these starting issues come from only a couple of things.
Weak battery and or too small a size wire for the starting system and or battery.
Carbs not synced,
Idle rpm too low or too high,
Old black colored starter. The newer gold colored high torque starter is better.
It doesn't turn faster just harder.
Using a primer system instead of the regular choke setup. (This is a big one.)
--------
Roger Lee
Tucson, Az.
Rotax Instructor & Rotax IRC
Light Sport Repairman
Home 520-574-1080 TRY HOME FIRST
Cell 520-349-7056
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=446418#446418
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: 912 80hp violent vibration on cold start |
Cheers,
The battery is brand new, cables are fine etc. Carbs are synced and floats are
fine. It does have the black start motor however it cranks over quite hard and
starts almost instantaneously,
The issue is when it starts it has an ungodly resonance for around 10-30 seconds.
In that time it won't accept any throttle response until it comes out of that
period then it runs smooth.
There are a few reports on the forums of indentical issues, however none seem to
report back with the issue or solution.
Michael
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=446419#446419
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: 912 80hp violent vibration on cold start |
Try increasing the idle speed or open the throttle a touch more at startup
Dave
> On Aug 25, 2015, at 8:16 PM, michaelrosenberg <mickyrosenberg@icloud.com> wrote:
>
>
> Cheers,
>
> The battery is brand new, cables are fine etc. Carbs are synced and floats are
fine. It does have the black start motor however it cranks over quite hard and
starts almost instantaneously,
>
> The issue is when it starts it has an ungodly resonance for around 10-30 seconds.
In that time it won't accept any throttle response until it comes out of
that period then it runs smooth.
>
> There are a few reports on the forums of indentical issues, however none seem
to report back with the issue or solution.
>
> Michael
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=446419#446419
>
>
>
>
>
>
>
>
>
>
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: 912 80hp violent vibration on cold start |
Micky, What is your startup procedure? How do you set the starting
carburetors and the throttle? What is your normal, all warmed up idle speed
?
Rick Girard
On Tue, Aug 25, 2015 at 8:16 PM, michaelrosenberg <mickyrosenberg@icloud.co
m
> wrote:
> mickyrosenberg@icloud.com>
>
> Cheers,
>
> The battery is brand new, cables are fine etc. Carbs are synced and float
s
> are fine. It does have the black start motor however it cranks over quite
> hard and starts almost instantaneously,
>
> The issue is when it starts it has an ungodly resonance for around 10-30
> seconds. In that time it won't accept any throttle response until it come
s
> out of that period then it runs smooth.
>
> There are a few reports on the forums of indentical issues, however none
> seem to report back with the issue or solution.
>
> Michael
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=446419#446419
>
>
===========
===========
===========
===========
>
>
--
=9CBlessed are the cracked, for they shall let in the light.=9D
Groucho Marx
<http://www.goodreads.com/author/show/43244.Groucho_Marx>
Message 6
| 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: 912 80hp violent vibration on cold start |
I have tried many different options for starting from a lot of different advice.
All options end with the same issue which is perfectly describe from Froghair
on the initial post of this thread.
Basically, cold weather starry is:
Fuel pump on (5secs or leave on)
Enriched on
Throttle closed
Start
Engine cranks over well and immediately fires and starts, resonance or shacking
happens for 10-30 seconds. Slowely removing enriched or adding throttle has no
effect. I can pith the throttle to the firewall and has zero response. Engine
probably resonated at around 1000RPM(ish)...... No throttle response means I
can not effect this.
Once everything smoothed out I warm it up at approx 2000RPM and it will idle around
16-1800RPM.
Once it moved out of this resonant time, it purrs.
I can only put it down to a fuel delivery or enriched issue. Once I get the engine
running smooth at idle, I added some enriched to see what would happen and
exactly the same symptoms occurred. Engine wound back to low RPM and resonated
again. I kind of expected it to happen in this scenario, how ever the starting
issue I have no control over.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=446424#446424
Message 7
| 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: 912 80hp violent vibration on cold start |
I may have had something similar. It turned out to be a sticking float that took
a few shakes to unstick.
Pete
Leander, Tx
Kitfox 3
> On Aug 25, 2015, at 8:16 PM, michaelrosenberg <mickyrosenberg@icloud.com> wrote:
>
>
> Cheers,
>
> The battery is brand new, cables are fine etc. Carbs are synced and floats are
fine. It does have the black start motor however it cranks over quite hard and
starts almost instantaneously,
>
> The issue is when it starts it has an ungodly resonance for around 10-30 seconds.
In that time it won't accept any throttle response until it comes out of
that period then it runs smooth.
>
> There are a few reports on the forums of indentical issues, however none seem
to report back with the issue or solution.
>
> Michael
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=446419#446419
>
>
>
>
>
>
>
>
>
>
Message 8
| 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: 912 80hp violent vibration on cold start |
Michael,
1000 RPM is way too low for idle on the Rotax 80 hp engine. It will always
run rough below about 1800 RPM, and idle speeds lower than that are very
hard on the gear box. I am not at all surprised to hear that your idle is
quite rough at 1,000 RPM. Your idle should be 1800-2000 RPM, minimum. If
it runs smooth at that speed, it's fine.
Regards,
Paul Kuntz
On Tue, Aug 25, 2015 at 7:31 PM, michaelrosenberg <mickyrosenberg@icloud.com
> wrote:
> mickyrosenberg@icloud.com>
>
> I have tried many different options for starting from a lot of different
> advice. All options end with the same issue which is perfectly describe
> from Froghair on the initial post of this thread.
>
> Basically, cold weather starry is:
>
> Fuel pump on (5secs or leave on)
> Enriched on
> Throttle closed
> Start
>
> Engine cranks over well and immediately fires and starts, resonance or
> shacking happens for 10-30 seconds. Slowely removing enriched or adding
> throttle has no effect. I can pith the throttle to the firewall and has
> zero response. Engine probably resonated at around 1000RPM(ish)...... No
> throttle response means I can not effect this.
>
> Once everything smoothed out I warm it up at approx 2000RPM and it will
> idle around 16-1800RPM.
>
> Once it moved out of this resonant time, it purrs.
>
> I can only put it down to a fuel delivery or enriched issue. Once I get
> the engine running smooth at idle, I added some enriched to see what would
> happen and exactly the same symptoms occurred. Engine wound back to low RPM
> and resonated again. I kind of expected it to happen in this scenario, how
> ever the starting issue I have no control over.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=446424#446424
>
>
Message 9
| 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: 912 80hp violent vibration on cold start |
Oops, sorry, I missed the part about no throttle response, which is
obviously the real problem. Yes, it sounds like a fuel delivery issue, but
I don't have any good ideas to offer.
Paul Kuntz
On Tue, Aug 25, 2015 at 9:03 PM, Paul Kuntz <paul.r.kuntz@gmail.com> wrote:
> Michael,
>
> 1000 RPM is way too low for idle on the Rotax 80 hp engine. It will
> always run rough below about 1800 RPM, and idle speeds lower than that are
> very hard on the gear box. I am not at all surprised to hear that your
> idle is quite rough at 1,000 RPM. Your idle should be 1800-2000 RPM,
> minimum. If it runs smooth at that speed, it's fine.
>
> Regards,
> Paul Kuntz
>
> On Tue, Aug 25, 2015 at 7:31 PM, michaelrosenberg <
> mickyrosenberg@icloud.com> wrote:
>
>> mickyrosenberg@icloud.com>
>>
>> I have tried many different options for starting from a lot of different
>> advice. All options end with the same issue which is perfectly describe
>> from Froghair on the initial post of this thread.
>>
>> Basically, cold weather starry is:
>>
>> Fuel pump on (5secs or leave on)
>> Enriched on
>> Throttle closed
>> Start
>>
>> Engine cranks over well and immediately fires and starts, resonance or
>> shacking happens for 10-30 seconds. Slowely removing enriched or adding
>> throttle has no effect. I can pith the throttle to the firewall and has
>> zero response. Engine probably resonated at around 1000RPM(ish)...... No
>> throttle response means I can not effect this.
>>
>> Once everything smoothed out I warm it up at approx 2000RPM and it will
>> idle around 16-1800RPM.
>>
>> Once it moved out of this resonant time, it purrs.
>>
>> I can only put it down to a fuel delivery or enriched issue. Once I get
>> the engine running smooth at idle, I added some enriched to see what would
>> happen and exactly the same symptoms occurred. Engine wound back to low RPM
>> and resonated again. I kind of expected it to happen in this scenario, how
>> ever the starting issue I have no control over.
>>
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=446424#446424
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
Message 10
| 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: 912 80hp violent vibration on cold start |
Have you tried this. This technique was developed by a neighbor and fellow
Kitfox builder owner. His engine is one of the very early 912 ULSs - long
before slipper clutches and soft start modules. I also use it on my 80 hp
and it starts running very smoothly. This is the method. Throttle full
out, pull choke - ignitions off, crank for ten to fifteen seconds. Wait ten
or fifteen seconds throttle in one to 1-1/2 turns. Ignitions both on, pull
choke crank. Mine usually starts over revved a tad but smooth as glass.
Lowell
--------------------------------------------------
From: "michaelrosenberg" <mickyrosenberg@icloud.com>
Sent: Tuesday, August 25, 2015 7:31 PM
Subject: RotaxEngines-List: Re: 912 80hp violent vibration on cold start
> <mickyrosenberg@icloud.com>
>
> I have tried many different options for starting from a lot of different
> advice. All options end with the same issue which is perfectly describe
> from Froghair on the initial post of this thread.
>
> Basically, cold weather starry is:
>
> Fuel pump on (5secs or leave on)
> Enriched on
> Throttle closed
> Start
>
> Engine cranks over well and immediately fires and starts, resonance or
> shacking happens for 10-30 seconds. Slowely removing enriched or adding
> throttle has no effect. I can pith the throttle to the firewall and has
> zero response. Engine probably resonated at around 1000RPM(ish)...... No
> throttle response means I can not effect this.
>
> Once everything smoothed out I warm it up at approx 2000RPM and it will
> idle around 16-1800RPM.
>
> Once it moved out of this resonant time, it purrs.
>
> I can only put it down to a fuel delivery or enriched issue. Once I get
> the engine running smooth at idle, I added some enriched to see what would
> happen and exactly the same symptoms occurred. Engine wound back to low
> RPM and resonated again. I kind of expected it to happen in this scenario,
> how ever the starting issue I have no control over.
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=446424#446424
>
>
>
Message 11
| 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: 912 80hp violent vibration on cold start |
My own experience with my second 912, an early 912S (before the ULS
designation). No clutch and HD starter.
Engine started violently shaking both carbs enough to aeriate the fuel
in the float bowls. This is why throttle above idle only caused more
shake, aggravated the situation, and no increase in rpm. Before Rotax
came out with the clutch/HD starter upgrade (at owners expense) my start
procedure was by the book with the exception of cracking the throttle to
about where 2,000 rpm would be. This helped some, but the startups were
still violent and put a lot of stress on the engine and the airframe.
When the update became available for the 912S, I had Ronnie Smith of
South Mississippi Light Aircraft, Lucedale, MS, install. From that
point on, the 912S started like a baby when book procedures were
followed, summer and winter. Idled nice and smooth.
My current 912ULS had the clutch and HD starter from the factory. Never
had a start problem with it as long as I kept the spark plug gaps closed
up to about .020".
john h
Kolb MKIII, N101AB
Hyder, Alaska/Stewart, BC
From: owner-rotaxengines-list-server@matronics.com
[mailto:owner-rotaxengines-list-server@matronics.com] On Behalf Of Paul
Kuntz
Sent: Tuesday, August 25, 2015 9:07 PM
Subject: Re: RotaxEngines-List: Re: 912 80hp violent vibration on cold
start
Oops, sorry, I missed the part about no throttle response, which is
obviously the real problem. Yes, it sounds like a fuel delivery issue,
but I don't have any good ideas to offer.
Paul Kuntz
On Tue, Aug 25, 2015 at 9:03 PM, Paul Kuntz <paul.r.kuntz@gmail.com>
wrote:
Michael,
1000 RPM is way too low for idle on the Rotax 80 hp engine. It will
always run rough below about 1800 RPM, and idle speeds lower than that
are very hard on the gear box. I am not at all surprised to hear that
your idle is quite rough at 1,000 RPM. Your idle should be 1800-2000
RPM, minimum. If it runs smooth at that speed, it's fine.
Regards,
Paul Kuntz
On Tue, Aug 25, 2015 at 7:31 PM, michaelrosenberg
<mickyrosenberg@icloud.com> wrote:
<mickyrosenberg@icloud.com>
I have tried many different options for starting from a lot of different
advice. All options end with the same issue which is perfectly describe
from Froghair on the initial post of this thread.
Basically, cold weather starry is:
Fuel pump on (5secs or leave on)
Enriched on
Throttle closed
Start
Engine cranks over well and immediately fires and starts, resonance or
shacking happens for 10-30 seconds. Slowely removing enriched or adding
throttle has no effect. I can pith the throttle to the firewall and has
zero response. Engine probably resonated at around 1000RPM(ish)...... No
throttle response means I can not effect this.
Once everything smoothed out I warm it up at approx 2000RPM and it will
idle around 16-1800RPM.
Once it moved out of this resonant time, it purrs.
I can only put it down to a fuel delivery or enriched issue. Once I get
the engine running smooth at idle, I added some enriched to see what
would happen and exactly the same symptoms occurred. Engine wound back
to low RPM and resonated again. I kind of expected it to happen in this
scenario, how ever the starting issue I have no control over.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=446424#446424
-
xEngines-List" rel="noreferrer"
target="_blank">http://www.matronics.com/Navigator?RotaxEngines-List
FORUMS -
eferrer" target="_blank">http://forums.matronics.com
b Site -
-Matt Dralle, List Admin.
rel="noreferrer"
target="_blank">http://www.matronics.com/contribution
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! --
|