VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > Model Specific > RV-8/8A
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 12-10-2017, 08:06 AM
andreskatz andreskatz is offline
 
Join Date: Dec 2014
Location: Dallas texas
Posts: 8
Default inadequate fuel flow on TO

I have a regular 360 lycoming engine with fixed pitch prop
barely broken in, 50s hrs after 12 years of work
on climb my CHT are very high (improved after 30 hrs but still high) and I cannot get enough fuel flow
I was told that the fuel flow can be improved by drilling or changing the needle that controls the flow.
any help and what needs to be done to improve flow by fiddling with the carb?
I have a precision carb LO-5193
any help appreciated
Reply With Quote
  #2  
Old 12-10-2017, 08:45 AM
pa38112 pa38112 is offline
 
Join Date: Mar 2008
Location: Clarksboro, NJ
Posts: 582
Default

What fuel flow are you seeing, and at what RPM? - FP or CSP ?
__________________
http://aprs.fi/N153MC
2004 RV6A Flying
Reply With Quote
  #3  
Old 12-10-2017, 10:08 AM
andreskatz andreskatz is offline
 
Join Date: Dec 2014
Location: Dallas texas
Posts: 8
Default fuel flow inadequate

14 gallons/hr fixed prop Sensenich 360 plain carbureted
thanks 2600 rpm
Reply With Quote
  #4  
Old 12-10-2017, 10:54 AM
az_gila's Avatar
az_gila az_gila is offline
 
Join Date: Jan 2005
Location: 57AZ - NW Tucson area
Posts: 9,549
Smile

Quote:
Originally Posted by andreskatz View Post
14 gallons/hr fixed prop Sensenich 360 plain carbureted
thanks 2600 rpm
I just checked one of my takeoffs.

15.5 gpm at 2400 rpm and 5,500 ft DA runway.

Sensenich FP prop O-360-A1A with carb.
__________________
Gil Alexander
EAA Technical Counselor, Airframe Mechanic
Half completed RV-10 QB purchased
RV-6A N61GX - finally flying
Grumman Tiger N12GA - flying
La Cholla Airpark (57AZ) Tucson AZ
Reply With Quote
  #5  
Old 12-10-2017, 11:46 AM
Bob Martin's Avatar
Bob Martin Bob Martin is offline
 
Join Date: Jan 2005
Location: Richmond, Virginia
Posts: 1,106
Default

Quote:
Originally Posted by andreskatz View Post
I have a regular 360 lycoming engine with fixed pitch prop
I have a precision carb LO-5193
any help appreciated
Andres,
I am not saying you have the wrong carb, but you do not have the normal carb we see for the 0-360 engine.
One normal is the MA4-5 10-3868...this one can be lean on some installs.
The richer version is the MA4-5 10-4164
There is lots of info in the archives about this topic and drilling jets.
__________________
Bob Martin
RV-6, 0-360 Hartzell C/S, Tip up, 1150+TT
James extended cowl/plenum, induction, -8VS and Rudder. TSFlightline hoses. Oregon Aero leather seats.
D100-KMD150-660-TT ADI2- AS air/oil seperator. Vetterman exhaust with turndown tips.
Louisa, Virginia KLKU N94TB
Reply With Quote
  #6  
Old 12-14-2017, 09:39 PM
andreskatz andreskatz is offline
 
Join Date: Dec 2014
Location: Dallas texas
Posts: 8
Default

txs for all responders
Reply With Quote
  #7  
Old 12-14-2017, 09:47 PM
PCHunt PCHunt is offline
 
Join Date: Feb 2007
Location: San Diego, CA
Posts: 1,522
Default

Quote:
Originally Posted by Bob Martin View Post
Andres,
I am not saying you have the wrong carb, but you do not have the normal carb we see for the 0-360 engine.
One normal is the MA4-5 10-3868...this one can be lean on some installs.
The richer version is the MA4-5 10-4164
There is lots of info in the archives about this topic and drilling jets.
I think what he may have is a Precision (Marvel-Schebler) MA4-5 10-5193 carb.
Not sure what that dash-number means.........

For the OP: Do a search here on VAF and look for drilling jet, or similar. Lots of info here on this forum.

Also, I see you are in the Dallas-Ft. Worth area. Find a local EAA chapter, there are several in the area. They can likely help you, as well.
__________________
Pete Hunt, [San Diego] VAF #1069
RV-6, RV-6A, T-6G
ATP, CFII, A&P

2018 Donation Plus, Gladly Sent

Last edited by PCHunt : 12-14-2017 at 09:50 PM. Reason: Add comment
Reply With Quote
  #8  
Old 12-15-2017, 06:01 AM
Raymo's Avatar
Raymo Raymo is offline
 
Join Date: Nov 2014
Location: Richmond Hill, GA (KLHW)
Posts: 1,710
Default

Sounds just like mine last Jan/Feb/Mar until I installed the gear fairings.

If you don't yet have your fairings installed, which apparently is the Vans recommendation during break-in, I think your numbers and temps are likely normal.

EDIT: I am running one P-Mag and decided to retard its timing a few degrees, which helped with CHTs until I installed the gear fairings.
__________________
Ray
RV-7A - Slider - N495KL - First flt 27 Jan 17
O-360-A4M w/ Catto 3 blade NLE, AFP FM-150 FI, 1 PMag, Vetterman Trombone Exh, SkyTech starter,
PlanePower Alt, FlightLines Interior, James cowl & plenum
All lines by TSFlightLines
NSDQ

"The object of the game, gentlemen, is not to cheat death: the object is not to let him play."
Patrick Poteen, Sgt. U.S. Army

Last edited by Raymo : 12-15-2017 at 10:32 AM.
Reply With Quote
  #9  
Old 12-15-2017, 07:08 AM
Captain Avgas Captain Avgas is offline
 
Join Date: Oct 2005
Location: Melbourne, Australia
Posts: 1,655
Default

Quote:
Originally Posted by andreskatz View Post
I have a regular 360 lycoming engine with fixed pitch prop
barely broken in, 50s hrs after 12 years of work
on climb my CHT are very high (improved after 30 hrs but still high) and I cannot get enough fuel flow
I was told that the fuel flow can be improved by drilling or changing the needle that controls the flow.
any help and what needs to be done to improve flow by fiddling with the carb?
I have a precision carb LO-5193
any help appreciated
Increasing fuel flow can be a fix for reducing CHTs on take-off. But if your FF is in fact already reasonable then putting a richer jet in the fuel control will only make the engine loose power (and thus produce less heat), and being over-rich can actually cause premature wear on the cylinders.

High CHTs on take-off in most cases is simply a matter of insufficient cooling and that is where I would look first. Check your baffle seals with the top cowling on by using a borescope to detect poor sealing. Oversized air dams in front of cylinders 1 and 2 can also obstruct airflow in a major way.
__________________
Regards
Bob Barrow
RV7A
Reply With Quote
  #10  
Old 12-15-2017, 03:11 PM
Capt Capt is offline
 
Join Date: Feb 2017
Location: Australia
Posts: 200
Default

That's good advice re the cooling baffles etc. especially the over-rich mixture for excessive cylinder wear.
As we all know a 360 produces around 160HP at T/off with a FP prop so the FF sounds about right. Still it's great to see so much help being handed out here, Vans sure did make a LOT of happy pilots
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 09:13 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.