mglavin

My Feedback: (31)

Here's a link to Sonictronics Gas pump. This thing is pricey but has no electric motor.


http://sonictronics.com/xcart/custom...cat=302&page=1

mstroh3961

My Feedback: (4)

the graylor is a sealed unit with a nylon gear pump in a nylon housing. It was desighned for solvents and fuels.

mglavin

My Feedback: (31)

Mike

Do you have one of the Greylor's? The end bell looks semi sealed?

The specifications suggest it's a chemical resistant pump. This means it was designed to pump corrosive chemicals. I'd be willing to bet the manufacturer does not recommend this pump for gasoline or similar flammable products. I also understand it’s popular and it works

bpryor

My Feedback: (45)

Actually, it is not sealed. People are sealing them themselves. If you don't, you're asking for trouble.

Here it is at Tower. http://www2.towerhobbies.com/cgi-bin...?&I=LXDJR7&P=7

I read in another thread that people have had trouble with them failing quickly.

You're right on Michael. In fact if you tell them you're using it for gas they won't sell it to you.

mstroh3961

My Feedback: (4)

I stand corrected....[&o] I looked at the able unit, they must seal it.

mglavin

My Feedback: (31)

The Sig Gasser looks a lot like the Kavan unit.

I was looking at Geistwares smaller red tanked unit, I see the larger one has the Sig pump now![&:] I thought it was a Kavan at first glance. It's all good,

Ben Diss

My Feedback: (23)

Here's a look at how I did it. In the other thread where Geistware first showed us his, I was not convinced on this motor. I came around once I realized what it's strengths and weaknesses are. The motor must be sealed. I cut a piece of G10 for the back and epoxied it in place. I also laid a bead of epoxy on the bottom where the heat sink joins the motor case. Sealing the motor is required so that sparks produced by the brushes can't ignite gas fumes.

Two other points on mine. I don't like the idea of charging the battery when sitting on a can of gas. I'm using NiMHs, but I remove it, thus no charge jack. The other thing is I believe in attended fueling. As such, I use a safety momentary switch to fill the tank. You must pull it out and then hold it up to fill and down to defuel.

bpryor

My Feedback: (45)

Hi Ben! Your setup is right on. It looks great too.....though I'm still going to stick with my trusty old pre-sealed Kavan pump, though the Greylor looks like a good alternative if you go to the extra trouble of sealing it....and it does cost a bit more, which will be important to some people. The Sig also looks good if they have fixed their reliability issues.

**Hey Ben, I just noticed that you screwed the switch/battery box to the can. Have you had a leakage issues? Also, where did you get the switch? I assume it's a momentary in each direction for in and out?

Ben Diss

My Feedback: (23)

Yep, momentary to force me to monitor the fueling. I just spent the last half hour looking for my notes on the switch and I can't find the details anywhere. It took me a day to find the ****** thing too. It's a sealed momentary safety switch. It's wired so that UP fuels the plane DOWN defuels it.

I have not had a lick of trouble with the screws going through the side of the gas can. I used steel hardware with a nut on the inside (that was tough to do) and rubber washers between the can and the box. Works great. The only thing I need to fix, is that it leans when the gas level gets low in the can. I'm running 9 big D-cell 3600 NiMHs and they're a bit heavy.

Here's what I'm thinking of using to prop the heavy end up.

bpryor

My Feedback: (45)

Hi Ben,

I'm building a new setup (safer), so that's why I'm following these threads and asking the questions. I picked up a similar operating switch to yours, and I also bought a separate switch that had a removable guard on it that I'm transferring to the two way switch that didn't come with a guard. That's about the only thing I don't like in your setup is that if you put the can in a car it may move and bump the switch to on and away the gas goes. I didn't want two switches as I've seen on some other setups, but didn't want it unprotected either.

Isn't that overkill? I'm going to run a couple of old 2700mah sub-c packs, and figured that was overkill. I too plan on removing the battery to charge....ahhh, is that why the big packs, so you don't have to remove them very often?

Dang, I don't think I have any of those lying around, where can I buy some?

CCDave

My Feedback: (53)

Here is a few pictures of the system I made...


Notice the end of the pump is sealed... You need to make sure that gas or gas fumes don't reach a spark... Also when you order your pump from greylor don't tell them it is for gas... They won't sell it to you...

Charlie P.

I've been using a Dave Brown's Six-Shooter manual pump for glow and figured his gas model will be my choice for my upcoming gasser. Fool proof and has never let me down. Takes me 30 seconds to fill a 12 oz tank. That's a minute for a 24 oz. Slow, but bulletproof.

bpryor

My Feedback: (45)

I have a gas/diesel one that I've had forever that I use for smoke oil. You're right it is bullet-proof, but I sure am lazy and hate the cranking.

Ben Diss

My Feedback: (23)

Bill- A safety switch cannot be bumped on. You have to physically pull the switch out and then move it up or down. As for the batteries, I had them lying around and I want as much capacity as I can get so I don't have to charge often. I think I can add one more cell and I may just do that to bring it up to the 12V max.

-Ben

bpryor

My Feedback: (45)

Ahh, yes, I remember those from my race car days. They have little notches on the bottom that prevent it from being pushed, and there is spring tension you have to pull against. I probably should have tried to find one of those. I wish you remembered where you got it, or maybe someone else knows where to look.

rmh

Rocker types -push either way to ON are common (Momentary ON center OFF 3 way)-will work fine-they are also commonly available to fit in a U shaped bracket which prevents anything bumping and actuating them.
Also -----
If you use extremely large tubing throughout the system -right to the fill tee in the model -- the fill process is far faster and pressures can be lower.
For safety sake - you can add an adjustable bypass on the pump which will regulate flow to the model.

Yeaaaaars ago- we setup an ALGON fuel injection system on a blown Chrysler which had an adjustable bypass- HILBORN, used small selectable orifices which could determine bypass --- same result as the NET pressure to the injectors was adjusted.
Ideally you want a low pressure /high volume delivery, just like at the local Gas n Go
High pressure delivery can easily make a tight stream of fuel-which is sorta how flame throwers work-----

AEROSHELDON

My Feedback: (99)

Ben, when I saw the pic of just shoes I thought the spark got to the fumes and you blew up and this was all that was left of you!! I'm glad to see you're allright.

Ben Diss

My Feedback: (23)

Found it!

It's a C&K 7205K2. It's ON-MOM-ON (7205), locking (K2). [link=http://www.ittcannon.com/media/pdf/catalogs/Leaf/SW_toggle_7000.pdf]C&K's catalog page [/link] shows all the various options for the switch.

[link=http://www.ittcannon.com/]ITT's[/link] website has a stock check function but it doesn't list this part. [link=http://www.onlinecomponents.com/]Online Components[/link] shows three different 7205K2 listing on their site but all are backordered.

I'd call Online Components and see what they can do.

-Ben

bpryor

My Feedback: (45)

Thanks Ben, I checked a couple of places locally but couldn't find one, so I'll see if I can't track one down through your links.

Panzlflyer

My Feedback: (15)

I still dont see why you guys dont use an inline VW hop up pump that pumps both ways, is SEALED and designed for gas. By the time you fix up your Graylor you have about the same http://www.cbperformance.com/catalog.asp?ProductID=577

mstroh3961

My Feedback: (4)

never mind[X(]

Ben Diss

My Feedback: (23)

Andyt- That looks like a nice pump, but how would you get the fuel tubing over that big connector?

-Ben

Panzlflyer

My Feedback: (15)

just rig a 1/4 to 1/8 brass reducer...got the parts from Lowes in the plumbing section. The big thing is a filter that I dont use. Its been going 3 years now with a small inline filter..Slimline I think.
I looked at the Graylor but it did not seem remotely sealed to me, the Facets only pump one way, Sonictronic was expensive and one way and the Sig fell apart on me.

sweetpea01

My Feedback: (10)

all you guys worry about sparks and such coming from the fumes to pump etc.......Have you ever worried about starting your push lawnmower? Spark plug is on the outside, very close to the gas tank.

Model Aviation actually had a good article on electric pumps with gas.......Use outdoors and you are most likely safe as their won't be enough fumes in a concentrated area to ignite. Of course stranger things have happened, but cars have blown up also, do you not drive those?


Keep it simple.....No leaks in your pump, charge your battery away from the can (incase the battery fails) and always do your fill/defill outdoors in a well ventilated area and you'll be fine


Placing all those components inside a plastic or metal container isn't going to stop fumes from reaching those parts, unless they are pressure sealed!

GoeKeli

My Feedback: (18)

I'm just burning way too much fuel not to get something faster and more easy soon. I can see the pricing of the assembled units are about 3X the cost of the wholesale parts or 2X the cost of retail parts. I don't really have a problem paying for a high quality unit but if I can make one, then I know I should.

JOe