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Fuel Leak found, missing plug!

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I am late sharing this because I thought I might be the only one to miss this...OK no one else is as na?ve but I did find this same on another project in my area and thought it is now worth passing on.

In my first two flights I smelled fuel. Not comforting?so;
I started the investigation from the cockpit and worked both ways in the system. What I found was the tell-tale lines of blue coming from the engine baffling, right hand side. The trail originated from the fuel Divider (spider). Here was a fuel line fitting, capped with a red plastic thread on cap. Port is marked ?GAUGE?.

I purchased from Van?s a new IO-360-M1B and the fire wall forward kit. I may have missed something in the instructions?but found the answer in:

Page seven, note 2 calls out plugging the hole as I now did. The port was for a not often used pressure driven fuel flow meter.

Photo is of mine, with the pulled connector sitting on top and the needed plug installed.
No more fuel smell and I feel lucky.:eek:
All I can say is that you're relying WAY too heavily on "instructions" :eek:
 
Bruce,

I appreciate you sharing. I don't have FI, but sometime I might, and in any case, your alert will go a long way to helping others make fewer mistakes.

Thanks for posting.
 
Another option is to leave the fitting there and cap it with an AN cap you can buy from ACS.

Yes new engines come with protective plastic caps in various places but they all need to be removed and replaced with the 'real' parts. My confession is that I test-fitted my prop without pulling the plastic plug from it. Fortunately no damage and I was able to get it out after having pushed it into the bore.
 
Bruce,
Thanks for posting your findings. I read and re-read the instructions and sometimes still miss things. As for the poster saying you are relying on the instructions too much, some of us, that is all we have. Being in Oregon where you are, Im sure you had others look at your build and help you check things out. Sometimes - as in your case, things get missed by everyone. Glad you were able to figure it out and get the vent capped properly and posting so we all have a heads up and one more thing to add to the inspection list.
 
????

So, are you saying that you made it through the DAR inspection, along with at least 3 others looking at your plane, ground runs, leak checks, and then into the 1st phase - with this plastic cap in place? I find it hard to believe that no one caught this.
You are indeed a lucky one, and it's good to have this event posted here.
Carry on!
Mark
 
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That's the reason the caps are RED, so they are hard to miss!

Everyone should be doing a very thorough leak fuel check prior to first engine start. This means running the aux fuel pump (with mixture and throttle forward) while you check EVERY fuel device, connection and line from the pump forward for leaks. It takes a few minutes to do this and this fitting would have no doubt been leaking on the floor at this point.
 
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Experimental...Education and Recreation! I am glad people confess their mistakes on this forum. I am also glad there are experts that alo contribute. Those 2 entities combine to help extreme novices like me avoid bigger issues.

Bruce, thanks for sharing this. I hope you don't feel attacked and will continue to lend us your experiences good or bad. I truly feel this forum needs more of these sorts of confessions so we all learn from them. I, for one, truly appreciate it.
 
Experimental...Education and Recreation! I am glad people confess their mistakes on this forum. I am also glad there are experts that alo contribute. Those 2 entities combine to help extreme novices like me avoid bigger issues.

Bruce, thanks for sharing this. I hope you don't feel attacked and will continue to lend us your experiences good or bad. I truly feel this forum needs more of these sorts of confessions so we all learn from them. I, for one, truly appreciate it.

Hear hear! Well said.
 
Thank you to the original poster of this thread. It points out a problem with our experimental aircraft. Although we have good building instructions for the kit itself, the firewall forward area is weak in terms of documentation. There are so many different engine combinations that could be used that it would be very difficult to come up with a comprehensive all inclusive instruction sheet. This is why I promote hiring a professional aircraft mechanic to check your work. A leak check of the fuel system is a pretty common practice in the certified world after any work has been done to the fuel system.
When I am done with a project, before first flight, I hire a mechanic to come and critic/check my work. I have built 10 planes. He always finds something that was missed by myself, the inspector, other builders. Usually all he finds are minor, potential wear issues, but he most certainly would have found this red cap!
Pay a few bucks and get a pro to look over your project, every time. I do my annual every year and then get the same guy to look over the engine, compression, timing etc. It costs next to nothing in the big picture of annual costs and gives me a great piece of mind.
Just because we have the right to do everything ourselves does not mean that we have to. Do you do the tune up on your car?
 
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Thorough leak checks are crucial ...

Good on ya, for the post! Never hurts to check another detail before going airborne.

Against many recommendations, I did ground runs and taxi tests totaling 1.4 hrs before my first flight, to assure that ALL the engine controls, idle adjustments, etc worked before that first flight ... and more than anything else, to check for fluid leaks of any kind. Engine "lore" said that much low speed operation risked glazing the cylinders on the new IO-320, but I simply would not make that first flight w/o some confidence in the integrity of the FFW systems and engine operation. And yes, I DID find some small fluid leaks, though the defective and eventually-leaky Red Cube (that vexed me for a month!) didn't show up until about 7 hrs.
 
I gotta say this. It was a really dumb thing to do. Welcome to the club. I've been doing this for a long time and on the last 10 I hooked up a really nice drain line for the manifold valve and since the gage port had a flare fitting on it I just screwed it on there. It sat there in plain sight for months until I did one last scan before first engine run. My eye finally noticed that the drain fitting was in the same plane as the injector lines. I blinked at it as I realized the 'duh' gene was alive and well and still an integral part of me. Took about 2 minutes to swap ports.
 
Bottle Check

Thank you to the original poster of this thread. It points out a problem with our experimental aircraft. Although we have good building instructions for the kit itself, the firewall forward area is weak in terms of documentation. There are so many different engine combinations that could be used that it would be very difficult to come up with a comprehensive all inclusive instruction sheet. This is why I promote hiring a professional aircraft mechanic to check your work. A leak check of the fuel system is a pretty common practice in the certified world after any work has been done to the fuel system.

An extra set of experienced eyes are well worth the price. I had the good fortune of Bill Marvel assisting in our build. He recommended a bottle check of the IO system...okay, four same size glass bottles taped to the cylinder heads with injection lines in each bottle, 30 seconds on the boost pump. There you have it or in some locals, Bob's your uncle. Place your bottles next to each other to confirm an even flow to each cylinder. Never would have been aware of the test without Bill's assistance.
 
I just took that fitting out out of the flow divider and installed the plug removed to install the oil pressure fitting. The fitting removed from the flow divider looks like a nice little restrictor fitting that will work perfect for the manifold pressure take off on the lower back of the #3 cylinder. The fitting provided in the Vans manifold pressure kit was not a restrictor fitting and it was aluminum. Anybody see an issue with using the removed restrictor fitting?
 
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