Vertical Draft FI Fuel line routing

I am trying to decide out how to run the fuel line from my Bendix Servo, vertical updraft style, which is mounted on a Lycoming O-360 converting it to FI from Carb, to the fuel divider on the top of the engine. I have Vetterman's x-over exhaust. I'm interested in pictures of anyone who has gone before me on this. The choice seems to be to run out the forward face output port, behind the exhaust x-over up thru the intercylinder baffel between cylinders #1 and #3, or.....run out the back face and back around the engine mount, up to the top of the engine thru the rear baffel. This makes the line about 42" long versus 22" the other way, but avoids the heating from the exhaust. There is only 1" between the forward x-over pipes and the sump. The line is a #4 line with firesleeve.
Marty RV-6A

I have the exact same issue and question. It looks like the shortest route is from the front of the servo up between the crossover exhaust and sump (only about 2" clear) up between the 1 and 3 cyliders to the spider. Any others done this? Comments?

Dave C
-7 FWF

I had the same issue. My servo is the Precison Silver Hawk experimental version of the Bendix. There are two high pressure ports, the forward facing one, and the rear facing one. I capped off the forward port and came out of the rear of the servo allowing me to route up and through the back of the baffle. Very clean and clear of exhaust and controls. Precision has drawings on their web site if this is the servo that you have. The Bendix may be different.

My plan..

Martyrv6a said:

I am trying to decide out how to run the fuel line from my Bendix Servo, vertical updraft style, which is mounted on a Lycoming O-360 converting it to FI from Carb, to the fuel divider on the top of the engine. I have Vetterman's x-over exhaust. I'm interested in pictures of anyone who has gone before me on this. The choice seems to be to run out the forward face output port, behind the exhaust x-over up thru the intercylinder baffel between cylinders #1 and #3, or.....run out the back face and back around the engine mount, up to the top of the engine thru the rear baffel. This makes the line about 42" long versus 22" the other way, but avoids the heating from the exhaust. There is only 1" between the forward x-over pipes and the sump. The line is a #4 line with firesleeve.
Marty RV-6A

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Mine runs out the aft port, up behind the engine, through a hole in the baffles near the oil cooler, and into the flow divider. My servo came with a 90-degree outlet in the back that I had to swap for a straight outlet.

I asked Mattituck about this setup because most engines I see have the fuel line running down through the inner cylinder baffles on the right side. They told me that they run the line through the inner cylinder baffles on the horizontal induction engines, and they run it up the rear of the engine on the vertical induction models.

I really don't think it much matters where you run it. I was just trying to find a way to do it without purchasing new (expensive) hoses. Here are some pics of my general routing, although I haven't clamped it down yet.

-Geoff

Dave C.
Interested to know how you have 2" clearance, are you building a Rv-6 or -6A and are you using Vetterman's x-over pipes?

John J. Thanks for the tip, I'll check Precisions' web site. My Bendix is the same as the Silver Hawk or very close to it. Marty

Also, does it make any difference how long this fuel line is? Don Riveria believes in keeping this line as short as possible, but what operational difference does that make?

What sort of grommets are you guys using the pass the hose through the rear baffle?

AN931

Jamie said:

What sort of grommets are you guys using the pass the hose through the rear baffle?

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I used a standard AN931 rubber grommet.

-Geoff

Interested to know how you have 2" clearance, are you building a Rv-6 or -6A and are you using Vetterman's x-over pipes?

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Marty,
It may not be 2", I just looked at it with out measuring... but a think it is in that range, maybe 1.5". I'm building a -7, O-360-A1A lyc (converted to AFP/Percision FI) with vetterman crossover exhaust.
Dave C

Dave C.
I have only 1" between the Vetterman's x-over and the sump on my set up. I'm surprised there would be any difference.
Marty

Grommet and clearance

Standard rubber grommet and sealed in with RTV. There is no way I had two inches of clearance or any way I was comfortable taking a fuel line up through the cross over.
I routed up the right side. There is a lot of space there on my 6 baffle as Oil Cooler Lines, Fuel Pump Cooling tube, and other obstructions made the left side pretty messy.
I also located my JPI fuel flow sensor with a short line from the distributor to the sensor and then out the back baffle. With all of the cooling air in the plenum, it is one of the coolest places in the engine compartment and in line with the orientation and location on the pressue line where JPI wants it.
The installation turned out very sanitary.