[diesel-dude]

Getting down to the final stages of my 87 RC Cummins swap  (thank goodness). After cleaning out my fuel tank, installing a new VansAuto sending unit and filler neck grommet, I find  the tank (35 gallon) reluctant to take any more than 10 gallons of fuel. At about 9.5 gallons, the fuel backs up into the filler neck and that's about the end of it.
The vent hose on the neck is clear, so I'm not sure what I'm missing. I DID leave the roll-over valve in the neck. Should I have removed it?

 

[dodge82273]

must be a diff in the filler neck vent , diesel IS foamy when agitated , and will shut off the faster pumps .... 

 

[J10Mike]

must be a diff in the filler neck vent , diesel IS foamy when agitated , and will shut off the faster pumps ....

Yep. As it fills, I have to turn the nozzle to an extreme side and finish filling it with a trickle. But, it does fill the tank.

 

[diesel-dude]

I was actually filling from 5-gallon fuel cans in my driveway for the initial firing-of-the-beast. It was from those newer cans with no vent buttons and the shitty hard plastic nozzles that won't breathe and takes a month of sundays to empty  (thanks EPA... you'll burn in hell for that mandate).
I suspect I may have inadvertently filled the filler-neck vent hose with diesel while fighting that stooopid can!

On a side note, the RC's new heart runs great! Once I get the thing road worthy, I'll drive it into town and see if it acts any differently filling from a pump. Thinking I'll pull the filler neck and remove that check-ball / rollover valve while I'm at it. I'm certain it's not helping the cause.

 

[dodge82273]

remove the unleaded gas only little fill hole + flapper as well while yer at it , oh and I have seen , can't remember where , the yellow vents for sale to install on the dumb blue gas/kero cans ....

 

[diesel-dude]

The little hole and flapper are long gone. My gas cans have already been converted with the "for water jugs only" vent kits, but my diesel cans are still on the waiting list.

 

[dodge82273]

IF you think those public use cans are bad , look at the osha ( or whoever ) approved ones the government saddles its employees with , spring loaded handles No One can safely operate .....  spill all over is safe ?

 

[hmrdwn]

For what it's worth.  I did a cummins ramcharger, i left the rollover ball in the filler neck and have never had a problem with filling the tank.

 

[Mad Max]

I used the diesel filler neck and vent hose from the Cummins donor on my RC conversions and haven't had the problem either.  Diesel pumps are designed to flow very fast compared to gasser pumps, so using the the 'Cummins/donor/ filler neck and vents will kinda be required - otherwise you may have to set the pump at the first detent to get a slower flow

 

[stftruck]

You don't happen to have a low spot in the new vent hose that's got the fuel blocking the vent process?

 

[diesel-dude]

I really do think I managed to fill the vent hose with fuel while fighting with the slow gurgling cans.
There was indeed a low spot in my vent hose that likely held said fuel and created an air blockage. I ended up using zip ties to fasten the vent hose to the top of the filler hose in an attempt to alleviate the issue. Will report back when I try to add more.