MarcusJsutton

I'm sure lots of you 4-stroke engine users will have solutions to this one, but I'm new to 4-Strokes myself! I have a pumped OS91FS which I've run for some time without problems. The only dislike is regarding positioning of the vent pipe for the fuel tank. The only solution I could think of for positioning the vent pipe was to drill a small hole in the top if the engine cowling, and poke the vent pipe up through that, leaving a couple of inches inside the cowling so that I can pull it out and use it as a "tank full" indicator when re-fuelling. Doen't look too pretty. I now have an OS120 SurpassIII (with pump), which will be going into a different aircraft. I was planning on retaining the vent pipe within the cowl for good aesthetics, but that would leave me with the dilemma of how to tell when the tank is full during refuel. I certainly don't want to overflow the tank and fill up the cowling !!!

What's best to do for both neat installation of the vent pipe and being able to check when full during refuel ?

William Robison

My Feedback: (3)

Marcus:

For many years I have positioned the vent where I could slip a hose on it, and run the hose to a 2 ounce tank sitting on the ground. Then when I pump into the tank, when it's full I see the little tank outside starting to fill. Then I reverse the pump and pull the overflow back.

While I'm not an eco-freak this does keep from spilling fuel on the ground, it gives me a good indication of afull tank, and I don't waste the overflowed fuel.

You can hide the end of the vent pipe anywhere, with only two restrictions. You have to be able to reach it, obviously, and it needs to be above tank level to prevent siphoning.

The overflow tank works when using muffler pressure too, just disconnect the muffler line and run it to your catch tank when fueling.

Bill.

MarcusJsutton

Thanks for that Bill. One problem i've got is the aircraft I'm putting the OS into is a Giles202 and hence fully cowled. Looks like Im going to have to drill a small hole in the cowling for the vent pipe to come through. I might try bonding it (or retaining it somehow) flush with the cowling so it looks good. The overflow tanks a good idea...until now I just fill until I get a squirt from the vent, then back up half a turn.

William Robison

My Feedback: (3)

Marcus:

The catch tank is not an original idea of mine, I don't remember where I saw it first. But if you save an ounce of fuel on every filling it does add up, and among my other traits I'm cheap.

Haw.

Bill.

Don M.

My Feedback: (5)

On every plane I've ever had, that I didn't need the vent line hooked to something, I just ran it out the bottom of the cowl and have never had a problem with siphoning and no one can see it. Never having had owned an OS with a pump except a current 160 with a Perry, unless I'm missing something, I don't understand why you have to have the vent line out the "top" of your cowl, it's the highest point in your tank, isn't it ?????

William Robison

My Feedback: (3)

Don:

Sorry, I must have been thinking about a three line system. The outside end. with the vent running into the tank above the level of the fuel, can be positioned anywhere it is convenient.

Bill.

Jimmbbo

I like the catch jar!! Cheap is good!! [sm=thumbup.gif][sm=thumbup.gif]

I use a three line system, but seems if you take the silicone vent tubing and route it up above the top of the tank, give it a 180 degree turn down and secure it, you can run the rest of the tube anywhere you want (f'rinstance out the bottom of the cowl) without abnormal fuel venting.. [sm=confused.gif][sm=confused.gif]

Cheers!

Jim