26GT2 Starting Problem

Description:
-26GT
-Tuned Pipe
-18x6 Prop
-Run approx. 25 times
-Mobil 1 Racing 2T 2cylce oil, 93 Octane, Mixed 32:1
-Engine sits 6 days between runs
-Inline filter

My engine will not start unless I pressurize the fuel system by blowing into the fuel vent. What I noticed is that fuel is being drawn to the carburetor but not into the combustion chamber (Wet thumb but dry spark plug). Its getting worse with time because I only had to do this once before the first start of the day. But now its needing it for every start.
My thought is that the pump diaphragm maybe damaged? I Also, noticed Horizon Hobby does not list a replacement diaphragm?.
My engine is still under Warranty but this would/will be the second time its down for repair. The first time was for a failed ignition module. Man…when this engine is running its awesome but the down time is a disappointing.
All that being said, do you have any ideas or recommendations for me to try?

Thanks in advance,

FRC5, i got the same problem. Looks like MVVS support is AWOL.

When the thumb gets wet, but no gas enters the engine, that is not a carb problem.
Is your engine inverted?
You may have to readjust the idle needle (richer)

@ Jugflier. I know you like to bash MVVS. AWOL? We (Dar and I) try to support MVVS AND Evolution users. This is a personal effort done in our free time. It is not governed by MVVS nor Horizon. You would be more helpful if you showed a more positive attitude instead of pickin' on people who try to be of help.

There is a problem with the forum software that does not send out notifications anymore.

Pe,

I thought maybe you were getting frustrated with "Horizon" related questions and just gave up (or) on a extended vacation.
I do realize your not responsible for supporting everyone’s engine problems. But I gave it a shot to see if you would/could help. I have to admit I was a little surprised to not even get a "Sorry Can't Help You". But its no big deal, I moved on and found someone else to help me out. For future reference, would you rather not receive "Horizon" related questions?

Just FYI-
My engine installation includes a tuned pipe located at the bottom of the plane so its at about 110 deg. Someone else on this forum suggested the (L) needle may be a little lean, so I opened it about 1/32 in. and it now starts good and runs great.

Regards,
------------------------------------------

JUGFLIER,

Try the richer (L) needle setting by opening it up about 1/32 in. as it did work for me.

Regards,

I am not frustrated, though this is the MVVS user support
The engines happen to be alike.
BTW, it was I who suggested to richen up the idle. Glad it solved your problem.

Pe,

Well then, Thank you very much. I had the plane out today and the engine is still starting good and running great. I'm surprised as to how many complements I receive about the performance and sound of this engine. It's installed on a Funtana 100 so I think it's a bit unusual to hear that high performance "gasser" sound coming from it.

I've had high performance cars for many years and realize there are trade offs encountered with higher performance engines such as the MVVS/Evolution engines. Tuning just get more and more critical.

I'm learning more about this hobby every week thanks to people like yourself.

Regards,