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PostPosted: Sat Apr 21, 2007 7:56 pm
by daffy1029
Hi lazairkid,
How do you run the fuel lines for your electric pump? Does the Walbro carbs have to suck through the electric pump after the engine is running? If so what make of electric fuel pump is it? I have an electric fuel pump as well, but will not push gas to the Walbro carb (even when engine is turned over). I assume that the electric pump I have only puts out 4 to 5 psi. Good for float bowl carbs, but not for pumper carbs. And there is no way the Walbro carb can suck throught this electric pump that I have. I had no problems running the engines before, on the test stand, but now with the fuel so low in the airplane, I think the Walbro carb are having a hard time sucking the fuel. That's almost 4 feet of head. Daffy

PostPosted: Sat Apr 21, 2007 10:59 pm
by daffy1029
Hi lazairkid,
I just spent the last hour looking at all the help sites that you mention and found one about fuel lines. I think that may be a big part of my problem. I routed my fuel lines throught the wing (instead of under the wing like most Lazairs are), then up through the top of the wing, to the carb. So now I have the fuel line higher than the carb which really produces a lot of bubbles. When I had the engine on the test stand, the fuel line went straight up to the carb and worked great! So I thank you for helping me with one problem. This is the page that helped me, http://www.aerocorsair.com/id30.htm
As for the electric fuel pump, I would still like to know how you installed your pump and what type of fuel pump you used. I am trying to set mine up so that there is no restriction anywhere in my fuel line.
And I like your Solo set-up. Looking really good. The power is very good, like you say, it's hard to hold her back at full power. Daffy

PostPosted: Sun Apr 22, 2007 5:51 am
by xgary
Check out FACET fuel pumps.

They are 12 V and free flow while not turned on .
Might be a god option for a "boost" pump. ?

PostPosted: Sun Apr 22, 2007 8:04 pm
by lazairkid
Daffy
Shorty's right a gain.
It's a 12V 4psi facet pump with a built in bypass.
Has one inlet and one outlet, but the outlet is tee'd
off too two outlets "See pic".
I ran my line the old way to the engine.
The pump is only used to get the fuel to the carbs .
I turn on the pump and then hold down the diagram on the carb tell the fuel go in to the carb then turn off the pump and she's ready to start
Do not use both at the same time you can damage the carb pump over time.

PostPosted: Sun Apr 22, 2007 8:16 pm
by lazairkid
My lazair from the back

PostPosted: Sun Apr 22, 2007 10:43 pm
by daffy1029
Hi lazairkid,
I have one of those pumps, but it has a check valve in it. So it won't work for me, I would need to get one like yours or a more powerful one so I don't have to push in the diaphram (like the primer bulbs used before). If you shut your engine off for 15-30 min or more, will it start up again without the use of the electric pump? I would like to be able to restart while flying (I have electric start).
The pictures of your Lazair looks great! Have you had your plane up in the air yet?
Thanks for the reply. Daffy

PostPosted: Mon Apr 23, 2007 9:50 am
by lazairkid
B) Daffy,
The fuel pump has a one way valve so the fuel cant back down the fuel line
Yesterday when I pulled the lazair out to start the engines, There was fuel
all the way up the line, all I had to do is tap the diagrams just to get a bit of fuel in the engine and she started first pull, after that It restarted everytime, So it should work after soring around.
No I have not yet got off the ground, but hope to before the fly-in we are
having May 12. I'm just trying to get the engines running perfict right now.
I didn't get to tune the engines yesterday, A friend of mine did his solo
in his Sonex at a nearby airport so there wasn't anyone at owe airport to
sit in the lazair for me to tune them.
I had to make up a wooden dowel 4 ft long so I can adjust the carbs standing
behind the wing. It was to dangerous setting under the wing, that prop was right there.
Lazairkid

PostPosted: Tue Apr 24, 2007 5:20 pm
by daffy1029
Hi lazairkid,
I should have known better, of course you need some kind of one way valve inside of pump, to pump fuel through. I will try the set-up again and if I can start it after 15-30 min with out electric fuel pump, then maybe I have to rebuild my carb.
That's a really good idea about using a wooden dowel for tuning the carbs. You could even carry it with you on the plane. I find the carbs are very touchy to set-up. Daffy

PostPosted: Wed Apr 25, 2007 6:44 pm
by daffy1029
Hi,
I just reread my previous post and it should have read "if it can start it after 15-30 min, then maybe I don't have to rebuild my carbs". Sorry about that, I am just getting over a bad cold. Daffy

PostPosted: Wed Apr 25, 2007 9:05 pm
by lazairkid
Daffy,
When you made the mounts for your solo 210's did you take into consideration the angle of the wings. Man I didn't, The engines tilt
with the wings, It works good for the engine with the carb heading up,
the fuel go right in with no problem but the right engine the carb is
heading down witch makes it harder for the fuel to go in to the engine to start.
I got them tuned up tonight and did 2 taxi runs, man they sound good.
It was hard to go straight down the runway, I kept over conpensating
and zigzaging down the runway but I was getting the hang of it. my
first taxi ever in the lazair.
Taxing, I was getting 240 on the CHT'S. and 800 on the EHT"s.
But this droped as I added power.
Full power I got right now 5200 RPM's. I Have some more tuning to do
once I get them broke-in.
Once I got the engines started and wormed up and did the first taxi, I
came back shut them down waited 5 min then cranked them back up with out
the fuel pump. so you shouldn't have any problem in the air.
I lined up on the runway "grass strip now", and applied half power and man she wonted to leap in to the air.

Lazairkid