Slow filling of Auxiliary Fuel Tank

[ibsteve]

My '97 GL1500 CSC trike is painfully slow when filling the auxiliary tank. I can tell when I reach the point of filling the aux. tank as it starts backing up in the fuel fill tube shutting off the gas pump. I then have to wait for a minute and it will then fill for about 7-8 seconds or so and shut off again. Fill and repeat for about 8-10 minutes AFTER the main tank fills. Frustrating.
minutes! This system does not use a pump and is the tank is vented to the fill spout to supposedly accommodate the aux. tank being installed lower than the main. It is installed to factory specs and CSC has not returned my email inquiry on this. I hate to not be able to use the aux. tank on longer trips.... Frustrating. Any thoughts?
Thanks, Steve

[bikerbillone]

I've found that to a bit of a problem on my RS aux tank fill but getting used to it. Ya get to 4.5 gallons, best shut it down, even though the aux tank is rated to hold five gallons.

[SEABILL]

Steve,

Have you checked that the vent tube is not being restricted somewhere? On my GL1800 there were a couple of places that the vent tube could easily get pinched.

I also found that CSC did not respond to my e-mails, but had good luck when I called them. They do prefer that you contact the installer first.

Best of Luck!

[ibsteve]

Thanks guys, I'll check the vent tube and I have a call in to CSC tech now.

[ibsteve]

Just a follow up for those that might be interested. CSC called me back as promised and indicated that this is normal for filling the auxiliary tank. He did say to slow the pump nozzle flow down to as slow as it will go when the aux. tank starts showing evidence of turning off the nozzle. This is what I had resorted to already and it is still slow but faster than before.

[Calgary]

Given the cost to have the auxillary fuel tank installed, it would not seem unreasonable to me to expect CSC to re-engineer the fuel tank to work properly. I can see where frustration can and will easily set in if one has to fiddle with the fill for an additional 8 to 10 minutes as reported by some. (I don't read that Roadsmith and Hannigan owners report these problems).

Has anyone asked CSC if they are designing a tank to work properly?

For long distance riders who will fill three or more times a day, that translates to spending an extra half to three quarters of an hour fiddling with getting fuel into the auxillary tank.

Has anyone had the tank re-designed on their own?

This fault alone could be a reason not to purchase a Viper.

I just went to the CSC site and read their installation instructions for their fuel tank. Their ending comments are:
NOTE: The Auxiliary Fuel Tank will fill and drain directly
off the OEM fuel tank. When filling the tanks, there may be a slight delay in the transfer of fuel from the OEM tank to the Auxiliary tank. Allow the fuel to migrate to ensure a complete fill-up.

CSC states there might be a slight delay in the transfer of fuel and some users report it takes 8 to 10 minutes. There's a big difference between those times!!!!

[bikerbillone]

I see that as a downside as well. No fun wasting time with that, especially if you get the dreaded "blow back".....

[SEABILL]

I was pleasantly surprised when I first filled my tank after adding the auxiliary tank.

After reading a number of posts about the time it took some folks to fill up, I was expecting it to be a long drawn out procedure.

Considering I was adding 3.5 gallons more fuel to the tank, it didn't really didn't take that much longer.

[carbco]

I have just installed an aux. tank on my '11 CSC Cobra XL kit. Per CSC instructions I just fill the stock tank then wait for a few seconds until the level drops in the main tank then fill again. It really doesn't take that long to fill them. Could you have a pinched vent line somewhere under the seat? You might want to check that? Another problem they had was there was a check valve in the older vent lines that could stop working and cause these problems. I see the trike you have is a '97. You might want to contact CSC and ask if your vent line has the check valve in it. Just some thoughts from previous posts on these forums. Mine works fine for me and even though it takes a little longer to fill both tanks I'm glad I can carry the extra fuel. Hope you get the problem resolved. Another Oregon TRiker

[ibsteve]

Carbcom, Thanks for the information. It is filling faster after I learned to let the main drain to the aux. etc. Still slow but much better.

BTW,I ride the Oregon high desert with some friends a couple times a year and sometimes return home via 126 through Sisters. Fantastic riding.

[07BlueCSC]

Sure it takes longer to fill the tank, you are putting in an extra 4 gallons.
With this set-up it would be nice to have larger fuel line to connect the two tanks but you do not need a separate fuel pump and wiring that could go bad. I get between 300 and
350 per fill-up. The extra MINUTE or so it takes to fill the tank is no big deal.

[ibsteve]

I

Sure it takes longer to fill the tank, you are putting in an extra 4 gallons.

Thanks for the heads up 07BlueCSC. I wish I had thought of that.