Comment

Comment by Jerry Bryan on February 9, 2011 at 8:33pm

In "my plane" photos, I changed the fittings several months ago. My fuel pump is 4 psi. Thanks for the help.

Comment by Michael Herder on February 9, 2011 at 8:24pm

A few things to consider here.   First off your workmanship looks great, but I too am cooncerned with the fittings even if they are rated for fuel b/c of temperature concerns.  If something ever does happen under the cowl and you are at altitude the last thing you want is fuel spewing out, same reason you've used firesleeve.  Also, these 90 degree fittings are essentially stress concentrations, at the place where you would least want one.  You want as much flexibility as possible.  Bear in mind that the engine is not solidly mounted, and your fuel sender is...  So any vibration or movement is transmitted directly to the 90 degree bend even if it is slightly dampened by the fuel hose. 

Another item, the accuracy of your fuel sender may be comprimised with the tight 90 degree turns right next to it.  The further away from bends the better off you are.  I'm struggling with accuracy right now and I'm using the same set up you are.

Also, I tinkered around with the idea of using a fuel pressure monitor and decided against after I talked with a rep with the manufacturer of the red cube fuel flow sys.  He pointed out and personally experienced more false alarms than anything else since the jab fuel pressures are so low about 3psi. 

 

Just some food for thought.  Everything elese looks great, and I especially like those vanes in the intake manifold.

Comment by Jerry Bryan on August 24, 2010 at 11:48pm

Mike, I have both fuel pressure and fuel flow sensors, so the manifold was the better choice than several "T's" Fuel comes through the firewall into the aluminum block. The lowest line goes to the mech. fuel pump, the upper line comes in from the mech fuel pump and the one out of the fuel flow meter (red) goes to the carb. Spruce sells two types of plastic fittings, these are for specifically for fuel. A poor country boy can't afford all brass.

Comment by Mike Schlichtman on August 24, 2010 at 10:11pm

Looks good...I did not know you were doing the manafold option. Are the plastic fittings aviation standards approved? I don't know, but just that I have never seen plastic used. I guess they would be fine. Where are the other two lines going...other than the one going to the carb.

Comment by Neil Corella on August 11, 2010 at 7:10am

Im building the same plane..same engine...I can use some feed back...I watched your video on the touque tube...I have the same problem. Not a very good answer when I called Zenith...what did you end up doing? Seems i need to build a wedge shaped shim...Im not happy with the plans..How about you? Thanks Neil