Would anyone here be able to post pictures of proper tank installation on skyray/flightsreak for the fp20/hayes tank combo? I want to make sure I set mine up correctly according to the Dirty Dan/Brett Buck description. I flew my skyrat yesterday for the first time, bench trim was pretty close but engine would start out too rich . About half way in to flight ran great and easily powered the plane through manuvers. Even tried launching with setting engine slightly beyond peak to the leanside hope it would fall back to the sweet spot. Wondering if my tank setup is not as directed in the DD/BB fp20 papers. In case it makes a difference Larry Fernandez was helping me .

The way I use hays tanks is to mount the molded vents to the outside.  This way the vent is a uniflow vent.  It has been working really well for us in the Dallas area.  You have to hold the plane with the nose up to fuel the tank.   The vent is either set up with muffler pressure, or in most cases we attach a small piece of 1/8 inch tubing to the top mounting lug of the engine and run the vent through that. The attatched picture if of a LA 46 setup, but the tank for the smaller motors is set up the same.

Mike: Not to hijack the thread (although I'm sure Gordon won't mind) I like that Hayes tank set-up pictured, very clean. To clarify: The pick-up is to the outside, overflow in middle, and uniflow vent inside? How is the internal tubing set-up? My guess is standard "clunk" for the fuel pickup, for the other lines, I'll hold off speculation. Looks like muffler pressure on this one as well. I only ask because I have been trying to get a similar (Sullivan) tank to work on a profile w/LA-46, so far not much luck. Thanks in advance.  

On the hays tank setup I use, there is no internal tubing other than the clunk line.  There are two molded in vents, and with the tank on the side i use the top vent, which is now on the side as the uniflow.  The vent just below is not drilled at the factory, I drill it out and use it to fill through.  I am running this as a uniflow tank with the uniflow at the very front of the tank.

Looking at the picture, the clunk line is attached to the black fitting, which is the inboard most line,  The outboard vent is being used as a uniflow with muffler pressure. The vent between is used to fill the tank. The airplane has to be held nose up to fill the tank.

Da Dirt used to mount the Hayes tank "upright", with the vents at the top. Last year or so, he changed to use the "top" vent to be a true uniflow, i.e., outboard with the tank's "shoe" flat against the fuselage side. Well, unless the tank was mounted on the inboard side of the nose. Always with muffler pressure, but sometimes with one or two extra NV Assemblies, apparently to make setting the needle more frustrating.

The Hayes tanks are the ones least likely to leak. I have tried two Sullivans and had problems with 50% of them...probably due to an elderly rubber plug...leaked like a stuck pig. I've used Hayes tanks on a "Skyrat" (I like it!  ) and the F'Twister with very good results, both with the vents at the top, "shoe" down, and with muffler pressure. The F'Twister is now in Tim's hands, and I expect it is still working well, despite the ugliness. I thought seriously about turning the tank 90 deg. and putting the top vent to work as a uniflow vent, but didn't like the idea of having to tip the plane to fill (either tail down or inboard tip down). I think Dan fills his with the inboard tip down. I just don't think it should be that much hassle to fly a model plane.    Steve

If you have the tank in the inboard side with the shoe mounted on the fuslage you have a suction tank, no uniflow. That would explain the rich to lean during the run that you have been getting.  with the shoe mounted to the center of the circle you have a uniflow tank, but being on the inside you will still have to set the engine a bit lean because the vent is inboard of the needle valve by about an inch. Assuming that the model is pulling 4g, that would be like setting the motor on the bench and then lifting the tank 4 inches into the air.

Would anyone here be able to post pictures of proper tank installation on skyray/flightsreak for the fp20/hayes tank combo? I want to make sure I set mine up correctly according to the Dirty Dan/Brett Buck description. I flew my skyrat yesterday for the first time, bench trim was pretty close but engine would start out too rich . About half way in to flight ran great and easily powered the plane through manuvers. Even tried launching with setting engine slightly beyond peak to the leanside hope it would fall back to the sweet spot. Wondering if my tank setup is not as directed in the DD/BB fp20 papers. In case it makes a difference Larry Fernandez was helping me .

Here Gordon,
Brett keeps asking me as I was taking this shot, " haven't you taking enough picture of my Skyray" .  I said its still the most FAQ on the Internet.



The next day, Brett installed a  brand new OS 25LA.  You need to get one of those!

Here Gordon,
Brett keeps asking me as I was taking this shot, " haven't you taking enough picture of my Skyray" .

   Actually, what I REALLY said was "Don't you think the world has enough pictures of this damn thing?"

    Brett

This is actually a picture of Dale Gleasons Big Ringmaster.  It had a stick of wood stuck into one side of the venturi to reduce the choke area.