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PostPosted: Sun Dec 09, 2007 11:00 pm
by uscgairdale
Left wing aileron belcrank before....

PostPosted: Sun Dec 09, 2007 11:01 pm
by uscgairdale
......and after!

PostPosted: Sun Dec 09, 2007 11:04 pm
by uscgairdale
Red fuel lines?.......Sure, why not?

PostPosted: Mon Dec 10, 2007 12:09 am
by lazairiii
Nice work bringing this back from the brink. The only question I have is the primer bulbs. I'd seriously reconsider using those. Besides, they aren't really necessary anyway. They have proven to be problematic with air and bubbles in the lines over the years. Try and have a continuous line from the check-valve filter in the bottom of your tank to the carb if at all possible.

Other than that, you've done a really nice job...good work!!

George

PostPosted: Mon Dec 10, 2007 8:16 am
by uscgairdale
George,

Yea, all the Lazairs that I've flown haven't had primer bulbs because it's so easy to just prime the Rotax 185's by hand. My KFMs do not have pumper carbs so I figure that I will need a way to prime the engines. Thats the only reason why I've put them on there.

Dave

PostPosted: Mon Dec 10, 2007 10:56 am
by JPXman
primer bulbs - when i first started rebuilding my bird shannon told me to stay away from primer bulbs. i thought "i need to prime my JPXs, its the only way!" so i installed primer bulbs.

daffy installed primer bulbs thinking the same thing.

after replacing them three times with 3 different kinds, having them all leak fuel and cause air bubbles, we threw them all out and came up with novel ways of priming the engines that did not involve primer bulbs.

daffy uses an electric fuel pump, and i use the "pump air into the tank vent" idea to push the fuel up to the engines. well, the methods are not novel i guess :)

stay away from primer bulbs.

and invest in some nice hose clamps, as you play with the fuel system you'll be making lots of changes and re-lock-wiring every connection gets tedious.

do your two tanks cross feed, or does each tank feed an engine?

PostPosted: Tue Dec 11, 2007 8:23 am
by uscgairdale
As always, thanks for the input, Tyler.

I remember what Shannon had to say about the primer bulbs and you're right about why I put them on. I wouldn't put them on a Lazair with 185s, but I figured that I HAD to but them on with the KFMs.

I set my fuel system up with a crossfeed. It makes for more connections in the fuel lines, but I like having more redundancy built into it.

PostPosted: Wed Dec 12, 2007 12:15 pm
by Shannon
The bellcrank and switch panel look sweet !

Tech Update 2.3 PRIMER BULBS

We have recently discovered that the major cause of those annoying air bubbles in the fuel line Is the primer bulb. If you're having this problem, the best way to get rid of it is to get rid of the primer bulb. This obviously makes it more difficult to get fuel to the engines Initially, but it should solve the bubble problem.

If you want to retain the primer, be sure it is positioned so that the outlet end of the primer is lower than the inlet end. This will reduce the possibility of trapped air in the primer entering the fuel line to the engine.

PostPosted: Mon Dec 17, 2007 9:26 pm
by uscgairdale
As always thanks for all the great advise guys. I haven't decided yet, but I may take off the bulbs and install an in-tank fuel pump.

Like always, I have more pictures of the restoration job. I marked a milestone today by completing my right wing once the wingtip was riveted on. All the left wing needs is the wingtip and the R1 top and bottom capstrips and then it's done too.

Check out the finished wingtip....

Dave

PostPosted: Mon Dec 17, 2007 9:29 pm
by uscgairdale
I also installed my intercom into the "lower console" today.

Dave