AHPowelson

My Feedback: (37)

I’ll be building my Matrix 3D this weekend. The fuel tank is located on the CG. I will be running an inverted Saito .82. Will I need a regulator (Cline or otherwise)? Is anybody NOT running one with acceptable results? Any input would be greatly appreciated.

Thanks,
Abram

Mettler1

I'm not sure if you will need a regulator but you will need a pump if you mount the tank at the CG. The carb will not pull fuel from that far away.

William Robison

My Feedback: (3)

Abram:

Either a pressure system with a regulator, or a pump.

I personally prefer the pump, a failure of the pressure sytstem can fill the plane with fuel.

Bill.

Hobbsy

My Feedback: (102)

A highly unlikely event after several years of using Clines and not having much luck with pumps.

NM2K

My Feedback: (14)

I like the Cline regulators best. They work. Plain and simple.

Pumps are cool too, but if it isn't built into the engine, like the YS, Enya, Webra, OS pumps, I stay away from them these days. Probably shouldn't. Just habit, I guess.

Ed Cregger

AHPowelson

My Feedback: (37)

Wow! The Cline Regulator is $60![X(] Does anybody have one they want to sell? (PM if you do!) Ouch. I was figuring $15-$20 max.. I may have to break down and buy one.. If I decided to go with the pump, what would be my best option? Thanks for the input, fellas.

JoeAirPort

My Feedback: (41)

Also try Ironbay, they are around $43.

William Robison

My Feedback: (3)

Abram:

I've had good results with the Perry VP-30, I have never used the VP-20 "Shaker" pump.

Joe:

I think you'll find the Iroin Bay and Cline are both priced near $60, but the Iron Bay is a metal body while the Cline is plastic.

Bill.

AHPowelson

My Feedback: (37)

What is the farthest practical distance the engine will draw fuel from? It looks like my fuel line from the tank to the carb will be 10-11". The tank to the muffler will be 11-12". I'm guessing this will be too much for reliable operation?

FenceMagnet

My Feedback: (2)

way too much....

go for the Cline... works GRRRREAT !!!!

[:-]

William Robison

My Feedback: (3)

Abram:

That set up should work very well with no pump or regulator. So long as all you do is level flight.

I don't think that's what you want to do though. Remember also that the distance from the engine to the tank is not the total distance - you have to measure to the back of the tank to get the total draw length.

Either put the tank up at the firewall or quit squirming on the hook. You're going to need one or the other to get decent engine run with the tank that far away.

Bill.

AHPowelson

My Feedback: (37)

You're right, Bill. It's time to suck it up and pick up a Cline. Does anybody sell it besides[link=http://www.billsroom.com/pcfs/products/CFS/fuelsysdesc.htm]here[/link]? I'd like to be able to order one now but I don't see any place to do so on their site. If not, I'll have to give them a call Monday. [:-]

William Robison

My Feedback: (3)

Abram:

So far as I know, that's it.

Bill.

Ernie Misner

A regulator can't possibly make any more pressure than what is available muffler pressure, only regulate or keep it more constant, right? So if unregulated muffler pressure varies, say between .1 lb. and .5 lb or whatever, would a regulator try to keep it at a more constant .3 or so? What happens if the throttle is chopped to idle long enough that all that is left is the .1 lb from idling and then the plane is suddenly pulled into a nose up attitude, with tank far back on the CG?

Thanks,

Ernie

William Robison

My Feedback: (3)

Ernie:

A check valve is puit in the line from the muffler. The tank pressure rises when running at high throttle, muffler pressures in excess of 20" water column have been noted. This pressure is held in the tank, dropping only as the fuel is used.

While the tank pressure does vary, and is falling while the engine is running at low throttle, the fuel burned at low throttle also is low volume so the tank pressure falls a lot less than you might think. And the regulator itself keeps the feed to the engine at the right level. Then when you open the throttle the tank pressure comes right back.

Bill.

Ernie Misner

Ahhh, the check valve, of course. In this way the regulator setup can actually "make more pressure". Of course we can use the check valve without a regulator but that seems to work poorly.

Thanks,

Ernie

FenceMagnet

My Feedback: (2)

the key to the regulator is that the fuel is not really supplied to the engine under "pressure" .... it is a demand flow regulator - the engine draws fuel from the regulator (only an inch-or-so away) and the regulator, sensing this demand or vacuum, opens and allows fuel to pass until the vacuum is no longer present.... the function of the tank pressure is merely to keep the regulator supplied with (potentially) more fuel than the engine needs.....

JoeAirPort

My Feedback: (41)

That is a very good explanation, please don't mind if I add a little of my own understanding. The inlet to the regulator is pressurized to around 5-10 psi via the engine case pressure, check valve and tank. The outlet pressure is kept at atmospheric pressure via the regulator's diaphragm and needle valve. If the engine sucks fuel and makes negative pressure at the regulator outlet , fuel is instantly supplied to the inlet of the regulator at 5-10 psi. It's a beautiful system and is the best solution for tanks on the CG.

Ernie Misner

Can muffler pressure be used with a regulator, or does it have to be crankcase pressure?

Thanks,

Ernie

William Robison

My Feedback: (3)

Ernie:

Normally muffler pressure is used. With the check valve it gets more than high enough to make the tank look like a semi-rigid balloon. Crank case pressure gets way too high for most installations.

Bill.

Ernie Misner

Once a guy plunks down his cash for a regulator, is there any problem servicing or keeping them going forever? Also, is there a "best price/place" for the cline?

Many thanks for comments!

Ernie

William Robison

My Feedback: (3)

Ernie:

I don't know of any source other than direct for either the Cline or the Iron Bay. Both about the same price, but as I said earlier, the Iron Bay has an aluminum body, the hose fittings are brass.

I have heard some few complaints about the plastic nipples breaking on the Cline, but nothing else, and never the first complaint on the Iron Bay unit.

Both use the Walbro regulator diaphragm, so the only part that fails is no problem to get. Your local lawn equipment shop always has them. Usually last about a year with glow fuel. Iron Bay does say they will keep giving you new diaphragms as long as you have their regulator, just send the old one and one buck US money.

Bill.

JoeAirPort

My Feedback: (41)

Jim Cline told me that the diaphragm will dry out if there is no fuel in the regulator and that's how they normally fail. He says to just leave fuel in the regulator over the winter and plug the inlet and outlet so the fuel stays fresh. He said they last up to 5 years without replacing the diaphragm. I'd keep the castor content to minimum though. It can gum up the innerds of the regulator.

FenceMagnet

My Feedback: (2)

"I'd keep the castor content to minimum though. It can gum up the innerds of the regulator."

nonsense.... if it's sealed with a loop of tubing, it won't dry up, a flush with some fresh fuel will quickly free it up.... no heat to form any permanent deposits.....

let's stop the castor bashing!

[:-]

JoeAirPort

My Feedback: (41)

I knew after I left that post I was going to start something. I kind of grinned and said, oh well.

On a more serious note, most people will not leave fuel in the regulator and will not seal it up so I still have a valid point. The castor will gum up over the winter. Jim Cline himself asked if I had castor in my fuel. I told him that I only have 1/3 castor in my oil mix and that it should not be a problem (I use Morgan 30/70 castor/synthetic).