Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

RV-List: Lycoming Engine Fuel Flow Problem...

 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> RV-List
View previous topic :: View next topic  
Author Message
TimRVator(at)comcast.net
Guest





PostPosted: Wed Nov 18, 2015 8:29 pm    Post subject: RV-List: Lycoming Engine Fuel Flow Problem... Reply with quote

After ruling out visible leakage and ensuring the mixture cable gives
full mixture range motion (to the stop on the carb), I think I'd
disconnect the fuel hose right before the carb and use the boost pump to
see the max available fuel flow rate to the carb. That could give you
some insight into blockages prior to the carb. This test (fuel flow
volume) is described in the old FAA Experimental Aircraft Flight Test AC
on page 23 (AC 90-89A, available at
https://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/23127).
FAA recommends seeking 125% of normal max fuel flow (and they tell you
how to estimate that value).

VR

Tim

--
Tim Lewis -- HEF (Manassas, VA)
A&P
RV-6A N47TD -- 1104 hrs - sold
RV-10 N31TD -- 650 hrs

Matt Dralle wrote on 11/17/2015 10:24 PM:
Quote:

Dear Listers,

I flew the RV-6 tonight that has a 1660 hour Lycoming O-360A1A with a Hartzell CS prop. I flew it 7 hours over a 3-day period about a week and a half ago with no issues whatsoever. Tonight, on take off, the EGT's all climbed into the 1450's right after take off and the CHT's were in the 400-450 range. The mixture was full rich. The engine didn't seem to be underpowered or rough but the fuel flow was about 9-10 GPH when it should have been in the 17-19GPH range. On the downwind I tried fiddling with the mixture with no change in making it richer. The mixture did make it leaner. I switched from the right to the left fuel tanks with no change. I have two fuel flow transducers one feeding the Skyview and the other feeding a Matronics FuelChec DX. Both were reading similarly low fuel flows at full throttle - 9-10gph. I didn't think to flip on the electric boost pump. But the flow definitely seemed restricted. The mixture control seems to have normal throw in and out a!
nd isn't binding and does lean the engine. I came in and landed with no issues.

I haven't pulled the cowling yet to have a look to see if its something obvious with the mixture cable, but what are some thoughts on what this could be?

Mechanical Fuel Pump?

Something in the Carb?

Plugged fuel line?

??

Thanks for your feedback,

Matt

-
Matt Dralle

RV-8 #82880 N998RV "Ruby Vixen"
http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
http://www.youtube.com/MattsRV8 - Matt's RV-8 HDTV YouTube Channel
Status: 260+ Hours TTSN - Version 2.0 Now Flying!

RV-6 #20916 N360EM "The Flyer"
http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
Status: 350+ Hours - Full Flyer Mode!

Matt's Livermore Airport Live ATC Stream!
Check out the live ATC stream directly from my hangar at the Livermore
Airport. Includes both Tower and Ground transmissions. Archives too!
For entertainment purposes only. http://klvk.matronics.com



- The Matronics RV-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?RV-List
Back to top
Display posts from previous:   
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> RV-List All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group