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  #61  
Old 09-03-2014, 07:41 PM
Captain Avgas Captain Avgas is offline
 
Join Date: Oct 2005
Location: Melbourne, Australia
Posts: 1,868
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Quote:
Originally Posted by Walt View Post
You should ground the aircraft and find someone qualified to help you sort this out before you become a statistic
This is still the best advice you have received to date. Dust off your cheque book and get some professional assistance.
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RV7A
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  #62  
Old 09-03-2014, 08:31 PM
bjohnson1234 bjohnson1234 is offline
 
Join Date: Oct 2012
Location: Scottsdale, AZ
Posts: 150
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Quote:
Originally Posted by Captain Avgas View Post
This is still the best advice you have received to date. Dust off your cheque book and get some professional assistance.
I don't have a problem paying someone, but at this point what are they going to do? Tear the plane apart trying to diagnose a problem with no current symptoms? I just had a conversation with Don at Airflow Performance about the engine quitting, the water in the airbox and the cleaning and at this point I feel pretty comfortable with it. On the ground the engine runs great from idle to full throttle hot and cold.

I have not been able to replicate the low fuel pressure with the mechanical pump, but the boost pump restored normal pressure so that's not an emergency issue. No problems with the ignition system and no symptoms of issues with the fuel controller. Tearing apart the plane looking for a problem can potentially create a problem. I know this fact is largely lost on the GA community, but most failures occur soon after maintenance or overhauls. There is a very reasonable explanation for the engine quitting, albeit an impossible one to confirm. I very much appreciate everyone's input and concern, but at this point I feel like the potential downside of messing with a plane that is running great outweighs the small possibility that something else is wrong.
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  #63  
Old 09-03-2014, 09:05 PM
Bevan Bevan is offline
 
Join Date: Sep 2007
Location: BC
Posts: 1,674
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Quote:
Originally Posted by bjohnson1234 View Post
Also, servo is precision model RSA-5AD1/2576535-A Serial #70242209
My Precision servo install instructions say to put a cleanable 30 micron filter either immediately before or after the mechanical fuel pump. Does your Usher gascolator have a screen and if so, what size is the mesh?

The Precision servo also has a very fine filter in the inlet but it has very small capacity. Considered to be a "last resort" filter. Have you checked this filter?

I don't see why the gascolator has to be on the firewall where it will pick up heat.

Bevan
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RV7A Flying since 2015
O-360-A1F6 (parallel valve) 180HP
Dual P-mags
Precision F.I. with AP purge valve
Vinyl Wrapped Exterior
Grand Rapids EFIS
Located in western Canada
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  #64  
Old 09-04-2014, 10:23 AM
FasGlas's Avatar
FasGlas FasGlas is offline
 
Join Date: Mar 2014
Location: Prescott, AZ
Posts: 739
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Quote:
Originally Posted by bjohnson1234 View Post
I don't have a problem paying someone, but at this point what are they going to do? Tear the plane apart trying to diagnose a problem with no current symptoms? I just had a conversation with Don at Airflow Performance about the engine quitting, the water in the airbox and the cleaning and at this point I feel pretty comfortable with it. On the ground the engine runs great from idle to full throttle hot and cold.

I have not been able to replicate the low fuel pressure with the mechanical pump, but the boost pump restored normal pressure so that's not an emergency issue. No problems with the ignition system and no symptoms of issues with the fuel controller. Tearing apart the plane looking for a problem can potentially create a problem. I know this fact is largely lost on the GA community, but most failures occur soon after maintenance or overhauls. There is a very reasonable explanation for the engine quitting, albeit an impossible one to confirm. I very much appreciate everyone's input and concern, but at this point I feel like the potential downside of messing with a plane that is running great outweighs the small possibility that something else is wrong.
This might be some more information for you. A friend of mine came in from Indiana last night and we got to talking about fuel injection systems. He builds and fly Pitts. Pitts having a metal fuel tank with a flop tube have a problem with very small metal particles getting into the fuel from the flop tube end hitting the metal tank. These particles are small enough to get by the servo filter and get stuck in the fuel divider. They cause the plunger to stick ( either open or closed ), the clearance is said to be .002. During their yearly inspection they disassemble every divider, clean and inspect them. He also says the Bendix dividers are less of a problem then the AirFlow dividers. Might be somewhere to look for your problem.
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  #65  
Old 09-04-2014, 01:39 PM
bjohnson1234 bjohnson1234 is offline
 
Join Date: Oct 2012
Location: Scottsdale, AZ
Posts: 150
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Quote:
Originally Posted by Bevan View Post
My Precision servo install instructions say to put a cleanable 30 micron filter either immediately before or after the mechanical fuel pump. Does your Usher gascolator have a screen and if so, what size is the mesh?

The Precision servo also has a very fine filter in the inlet but it has very small capacity. Considered to be a "last resort" filter. Have you checked this filter?

I don't see why the gascolator has to be on the firewall where it will pick up heat.

Bevan
I have a filter before the electric fuel pump, not sure if it's 30 micron or not and not sure about the Usher gascolator screen.

As far as the placement goes, I guess maybe no one wants to cut a hole in the floor for the drain inside the cabin.
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  #66  
Old 03-04-2015, 09:41 PM
bjohnson1234 bjohnson1234 is offline
 
Join Date: Oct 2012
Location: Scottsdale, AZ
Posts: 150
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Just an update - I have had no further issues and I believe the issue was ingesting water from the filter box. I have added a drain hole to prevent any future pooling.
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  #67  
Old 03-05-2015, 11:59 AM
Bevan Bevan is offline
 
Join Date: Sep 2007
Location: BC
Posts: 1,674
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What size hole? If I recall, the plans call for a 3/16 hole and often thought water wouldn't drain through such a small hole unless there was some pressure (vertical accumulation) but may not drain the last of the water. How much water in the filter bowl is too much?

Bevan
__________________
RV7A Flying since 2015
O-360-A1F6 (parallel valve) 180HP
Dual P-mags
Precision F.I. with AP purge valve
Vinyl Wrapped Exterior
Grand Rapids EFIS
Located in western Canada
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