Emptying The Gas Tank On The Bench

[mirion]

Gonna be painting the tins this winter and I have got the tank sitting on the bench about half full. (No, I didn't run it down this fall because I was stiil riding in late November and didn't know when that last ride would be) Getting it off wasn't a big problem thanks to the disconnect. I put the line into a gas can and open the petcock and nothing comes out. I assume that the diaphragm in the petcock is actually doing its job. Does someone know if there a simple way to actuate the diaphragm or do I have to tip the tank upside down to empty it?

[Joe Hummer]

You can put a vacuum hose on the diaphragm side of the petcock and suck it until you get flow...

I guess you don't have a mity vac...do you? 

Other than sucking on a hose, you could tip the tank on the nose, remove the petcock, then tip the tank back down and pour the gas into a can. 

Joe

[3W-lonerider]

i second that account,..put a vacuum hose on the nipple and suck on it till you get flow..then pinch the vacuum hose shut with vise grips..

[f6power]

Or get a $2 Hand operated siphone pump from Ace Hardware,works very well.

[BF]

Is putting it back on the bike and going for a ride out of the question?  If it's half full, about a 60 to 70 mile ride oughta do it. 

[Chrisj CMA]

Removing the petcock and then tipping the tank over a funnel into a gas can is the fastest and easist way.  I did that when I instaled the pingle.  I didnt need an empty tank, but I wanted to drain every drop to see if there was sediment.  It was very easy

[hubcapsc]

Removing the petcock and then tipping the tank over a funnel into a gas can is the fastest and easist way.  I did that when I instaled the pingle.  I didnt need an empty tank, but I wanted to drain every drop to see if there was sediment.  It was very easy

I "drained" mine a few months ago.

First I put a vacuum on the petcock and let that flow until it was just drips.

Shaking the tank let me know there was still gas in there.

So I took the cap off and turned it upside down. I can only imagine what the tank looks like on the inside, but it's not
just a "bulb", there's some passageways and a lip around the cap such that removing the cap and turning the tank
over still didn't get all the gas out. I sloshed it around over the bucket getting a little more out each time until
I thought it was "good enough" (I believed the gas in there was bad), but there was still a little bit in there.

Chrisj, I guess you got the last few drops out through the hole exposed by removing the petcock?

-Mike

[Chrisj CMA]

Yes, Mike........Like I said, my goal wasnt a bone dry tank so I was satisfied with almost bone dry.  Without trying that hard I bet I had all but a spoon full drained outta there

[alph]

Or get a $2 Hand operated siphone pump from Ace Hardware,works very well.

cheaper yet, just buy about 5 feet of plastic 1/4" tubing, stick it into the tank, suck on it until you get fuel up into the tube, then let gravity siphone out the rest.  the plastic tubing by me cost 30 cents a foot, you'll save 50 cents!! that's about a cup of gas's worth!

[mirion]

Thanks for many good ideas. I started by pulling a vacuum on the petcock with a Mightee Vac and still no flow and then it dawned on me that the Redeye disconnect has a check in it. I took the other half of the disconnect off and stuck it in the tank end and out comes the gas.....but, I released the vacuum and the  gas continued to flow. Does that mean a bad diaphragm or is there something I am missing regarding the operation of the petcock?

[Joe Hummer]

Probably means a bad diaphragm.  How much vacuum did you put on the mighty vac?  The motor only makes about 7" W.C.  If you put much over 10-15"...you probably poped the diaphragm (been there...done that).

Joe

[valkyriemc]

Probably means a bad diaphragm.  How much vacuum did you put on the mighty vac?  The motor only makes about 7" W.C.  If you put much over 10-15"...you probably poped the diaphragm (been there...done that).

Joe

I was gonna say, a mighty vac can- I would think- could put a hurting on a thin diaphram.... 

[lee]

A busted vacuum diaphragm does not let gas flow.  In fact it does just the opposite.
The valve will not open if the vacuum diaphragm has a hold in it.