solo 2350 engines

[Rocket]

Hello people,

I have a Ventus CM Self launcher, I was having starting proplems, so we
checked the plugs and the gaps and changed the airfilters.

The filters supplied were two piece and came off because they were two
piece and since that time I have had a loss of revs.

The battery has been replaced and now the engine starts really well all
the time but I still have a problem with loss of revs.

We have since put the old airfilters back on, cleaned them and also
changed the mixture setting.

Running the engine with airfilters off helped in prove the revs, to
6300 but not fully to 6400, and now is only getting 6300/6200.

It has been suggested any rubber from the airfilters that may have
fallen in the carbby would have been burnt up straight away.

While I am at the moment getting a good climb at 6200/6300 I would be a
lot happier if I started off with the 6400 I should have.

Any Ideas about what could be causing the loss of revs.

I have ordered new airfilters, the right ones

Rob

[bagmaker]

Rob,

some thoughts

any airfilter debris sucked in the carb MAY still be there, and WILL cause a problem if they are, however the effect shouldnt be at full RPM, more so, it will not start or will idle rough.
Take a look in the throats, if debris is there, do a full pull-down and inspect. Assuming the engine ran fine last time you flew, expect it to do so again or look for changes SINCE then.

first theory,
sounds too lean. Removing the filters will do that, improving airflow to the motor. If it was run too hard when lean you may have internal damage, scored bores or broken rings from overheating in the upper cylinder area.
Does the RPM increase or decrease as you get higher?
The higher you go the less oxygen, meaning the engine runs richer. As you get high with a lean engine, it will rev faster, to a point. As you get high with a rich engine it progressively decreases RPM.

so,

#1, GET new fuel, dont use the stale stuff in the tank
#2 remove the new filters (you do have new filters yet??) and run up to full power on ground, check all settings including EGT if possible. Run for some time, there may be thick, old oil within the motor that needs blasting out.
There may be an issue with piston ring, main or big end bearing due to debris from the filter, also a clogged exhaust will do the same.
#3 put filters back and repeat process, note any changes.
#4 if there is a difference you have a filter issue, if not, an engine issue.

2 stroke engines never run quite as well as they did just before they seize, so too rich is the best option.

disclaimer: I know nothing, dont listen to me
Its is completely possible following the above will cause you to ditch head first into a line of school buses, killing hundreds and leaving you in a chair. Get expert help and sue them-
Blasted American law system.


bagger

[HL Falbaum]

I had a similar problem on a DG800B Solo 2625-01. Engine would start, but
upon throttle advance, after reaching 4000 rpm, the revs and the EGT would
decrease. The engine would nearly die at full throttle. Turned out to be a
small leak in the fuel line near the carburetor that was sucking air, but
not leaking fuel. Took 1 month to find it-only found as the leak got bigger,
and started leaking fuel!

Running the engine without a air filter may not be a good idea depending on
location. If it is a K&N filter, properly lubed, and new, it should not be
the problem.

Good luck

--
Hartley Falbaum


"bagmaker" > wrote in message
...
>
> Rob,
>
> some thoughts
>
> any airfilter debris sucked in the carb MAY still be there, and WILL
> cause a problem if they are, however the effect shouldnt be at full
> RPM, more so, it will not start or will idle rough.
> Take a look in the throats, if debris is there, do a full pull-down and
> inspect. Assuming the engine ran fine last time you flew, expect it to
> do so again or look for changes SINCE then.
>
> first theory,
> sounds too lean. Removing the filters will do that, improving airflow
> to the motor. If it was run too hard when lean you may have internal
> damage, scored bores or broken rings from overheating in the upper
> cylinder area.
> Does the RPM increase or decrease as you get higher?
> The higher you go the less oxygen, meaning the engine runs richer. As
> you get high with a lean engine, it will rev faster, to a point. As you
> get high with a rich engine it progressively decreases RPM.
>
> so,
>
> #1, GET new fuel, dont use the stale stuff in the tank
> #2 remove the new filters (you do have new filters yet??) and run up to
> full power on ground, check all settings including EGT if possible. Run
> for some time, there may be thick, old oil within the motor that needs
> blasting out.
> There may be an issue with piston ring, main or big end bearing due to
> debris from the filter, also a clogged exhaust will do the same.
> #3 put filters back and repeat process, note any changes.
> #4 if there is a difference you have a filter issue, if not, an engine
> issue.
>
> 2 stroke engines never run quite as well as they did just before they
> seize, so too rich is the best option.
>
> disclaimer: I know nothing, dont listen to me
> Its is completely possible following the above will cause you to ditch
> head first into a line of school buses, killing hundreds and leaving
> you in a chair. Get expert help and sue them-
> Blasted American law system.
>
>
> bagger
>
>
>
>
> --
> bagmaker

[Ted]

Rob,
I have flown a CM for 7 years and have never seen over 6300 at a 49 kt
climb unless the belts were slipping. What CHT readings are you seeing?

Ted

On Jan 23, 6:17 pm, "Rocket" > wrote:
> Hello people,
>
> I have a Ventus CM Self launcher, I was having starting proplems, so we
> checked the plugs and the gaps and changed the airfilters.
>
> The filters supplied were two piece and came off because they were two
> piece and since that time I have had a loss of revs.
>
> The battery has been replaced and now the engine starts really well all
> the time but I still have a problem with loss of revs.
>
> We have since put the old airfilters back on, cleaned them and also
> changed the mixture setting.
>
> Running the engine with airfilters off helped in prove the revs, to
> 6300 but not fully to 6400, and now is only getting 6300/6200.
>
> It has been suggested any rubber from the airfilters that may have
> fallen in the carbby would have been burnt up straight away.
>
> While I am at the moment getting a good climb at 6200/6300 I would be a
> lot happier if I started off with the 6400 I should have.
>
> Any Ideas about what could be causing the loss of revs.
>
> I have ordered new airfilters, the right ones
>
> Rob