Tank Filler Modifications

[icanfixall]

I'm going to make the tank fuel filler mods but I don't understand how the tank will be vented to the outside. Seems removing the rollover valve will cause the tank to be a closed system. Am I missing something..

 

[trackspeeder]

The tank will vent at the fuel filler. The Super Duties are set up the same way. 90 degree fitting at the neck and a hose to the top of the tank.

 

[icanfixall]

How will this happen at the fuel filter??? I understand about the return line system but removing fuel from the tank will create a vacuum. Does the fill cap vent to atmosphere when too much vacuum is pulled on the tank.... Just trying to understand what I'm about ready to do.

 

[LCAM-01XA]

The fuel tank caps are of the self-venting type, yes, so there won't be much vacuum in the tanks, if at all. My tanks are connected to each other through a 1/2" overflow hose (this in case the darn TSV decides to get stuck on pumping from one tank but returning into the other), so they only vent through the caps, haven't noticed any issues with this setup and I've been running it for over an year now.

 

[jperecko]

How will this happen at the fuel filter??? I understand about the return line system but removing fuel from the tank will create a vacuum. Does the fill cap vent to atmosphere when too much vacuum is pulled on the tank.... Just trying to understand what I'm about ready to do.

he said filler, not filter... makes some sense.

 

[sootman73]

it vents through the cap the same way anyway. the original vent tube is inside the filler neck and the cap closes off both tubes when you put it on. as long as your caps vent it will be fine.

one of our trucks at work(FI 454) sucked two tanks in like pop cans cuz his cap(and the second one) didn't vent right. sucked them in so tight that the seam in the middle broke and leaked fuel!

 

[trackspeeder]

How will this happen at the fuel filter??? I understand about the return line system but removing fuel from the tank will create a vacuum. Does the fill cap vent to atmosphere when too much vacuum is pulled on the tank.... Just trying to understand what I'm about ready to do.

The fuel caps are vented. The main reason for the tank mod is so you can fill the tanks faster. The big plus is that you can use the high speed pumps to fill up. No constant clicking off of fuel pump because of trapped air.

 

[fields_mj]

I haven't heard of this mod, could someone explain it to me? So far I've filled up at every pump around, and I've only found ONE of them that doesn't click off on me. The rest give me fits, even the ones at the regualar gas stations (as apposed to a truck stop).

Thanks,
Mark

 

[88bigblue]

I found one that didnt click off on me, I think it was made in the seventies tho. I am kinda glad to see that im not the only one with this problem and would like to know how it can be fixed.

 

[hesutton]

My Crew cab is not modified yet and it drives me crazy trying to fill it up. I can fill an empty tank on my regular cab (filler necks modified) with the "big rig" pumps in less than 60 seconds and not spill a drop of fuel. No BS.

Heath

 

[icanfixall]

Update

Don't even think about pushing the internal piece down and then pulling it out. I'm real good wth a torch but.. I don't have one at home... So use a ball burr cutter on a grinder either air or electric. Collaspe it and then drive it out the bottom. I tried cruching this piece at the bottom.. Nope... Doesn't work. I almost gave up and went searching the wrecking yards for another neck. But I ended up using a map gas torch and almost melting the internal piece. Then it dropped out.... I cut a hole in the neck for the 3/4 street elbow and silver solidered it in place. Then coated it with permatex copper plus rtv. Now its curing and then I tackle the rollover valve on top of the tank. Seems a plastic street elbow and grind off some of the thrads making it look like what you just puled out and use a twisting motion going back into the rubber fitting. Justpushing the fiting into the tank will pushthe groomet into the tank. Then its fishing time. I will be using the twisting method ad some rtv just in case I have a possible grinding error....

 

[Sycostang67]

My front tank fills just fine, but the rear is a pain. The pump handle always clicks off instantly several times and then when I do get it going it will fill it, then the handle clicks off and a second later fuel comes gushing from the tank.

 

[riphip]

You can MIG the elbow in but braze it after to keep it from leaking. I can fill both my tanks in 4 minutes from empty.

Darrin Tosh, Thanks for the deal on the sunvisors. They look great and don't droop.

Rick

 

[fields_mj]

Does anyone have a picture of this mod?

 

[Mat J]

yeah i took mine apart to try and do this mod but I dont really get it. I didnt see an inner piece to take out. maybe someone else messed with it but it still fills terrible.