Jump to content

Fuel Cell filling


oddcarnut
 Share

Recommended Posts

So we had the new piggy, a 77 Volvo 242, former SCCA ITB heap out at VIR for the first time.  It has an ATL cell in it that came with the car.  The filler neck on top of the cell has the required flap for roll over sealing.  Here's my question as I've not had a race heap with a cell in many years.  Should we have to force that flap down in order to get fuel into it at some rate faster than a trickle?

For those with a cell and filler on top of the can, how are you determine when it is full without making a mess?  Our filler neck extends about 4 inches up from the cell case.  Our vent exits to the rear and is a bit higher than the top of the filler neck.

 

Any creative, and cheap fuel gauge solutions for a cell?  I may do an aircraft switch for a low warning light but am interested in knowing what others are doing?

 

BTW, donations of Volvo 240/740 drivetrain bits that are collecting dust and consuming your valuable storage space are welcome.

 

Ken

Link to comment
Share on other sites

No, it should fill very rapidly without outside help. Sounds like your flapper valve is suffering from age, less flexible than it should be and not opening under normal gravity and fuel weight as it should.

 

My installation uses a long clear filler tube that goes at a shallow angle to the outside filler location, makes it easy to see when the cell is full without spilling. My vent is below the top of the filler neck to drain off excess fuel through the vent and into the catch can/tray instead of overflowing up the filler neck or, in your case, into the car. Your vent being higher than the filler neck might siphon fuel out if your car is upside down; you should rearrange that to have the vent exit well below the filler neck and also to have a check valve in it.

 

I use a surge tank with a float that activates a shift light to let the driver know when the booster pump no longer is keeping the surge tank more than about 3/4 full. That gives my driver about 2 laps to warn the crew that he's running out of fuel and is coming in.  I made my float switch from the stock GM tank sender by moving the resistive wires away from the top part of the range to open the circuit when full, and hooking the sender output wire to a relay that turns on the shift light when the float moves down and completes the circuit to ground. As cheap as it gets if you have a sender sitting around.

Edited by mender
  • Like 1
Link to comment
Share on other sites

Our flapper is stiff as well, was when new a couple of years ago and still is.  15" of fuel hydrostatic will only dribble into the cell.  

 

Our fuel jugs have long hoses on the end that reach down into the filler hose to poke into the cell and hold the flapper open.  Then we fill as fast as the jugs can empty.  

Link to comment
Share on other sites

Our setup sounds just like Menders.  Vent below the fill and catch can for overflow through stock car style flapper vent.  Fills fast and virtually no spillage.

 

Our vent is similar to this:

http://www.ebay.com/itm/NEW-CV-Products-Billet-Aluminum-Fuel-Cell-Vent-Overflow-Check-Flapper-Valve-C1-/191975396985

 

 

 

Link to comment
Share on other sites

9 hours ago, red0 said:

Our flapper opens from the pressure of the fuel in the filler neck. I also run a clear vent line that acts as a sight gauge. 

 

Sorry, now Ovlov parts......only Saab for this Swede. :lol:

Thanks to all for the replies.  Yes, it is a bit sad that we went to the dark side of those Scandinavian cars.  But not to worry, there remain several 96, 95, 97 & 900 in the fleet, one being a drivetrain-less Sonett with a cage in it.  Wonder what class A creation could be created with something other than the Ford V-4 and SAAB bake-lite gearbox....

  • Like 1
Link to comment
Share on other sites

One thing we changed last year on our cell was the vent size.  We increased the size to max allowed in the rules...I think it was 3/4" ID...maybe OD.  Our total time per can of fuel dropped to as fast as the fuel would leave the jug.  Huge improvement!!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...