I'm in the process of rebuilding a 69 F350 CS and when I got it the main tank had been removed and the auxiliary tank wasn't connected. It was originally an RV and the camper had rotted away, so one of the previous owners tore it off. From what I can tell, the fill tube for the aux tank connected to the lower left corner of the camper, just behind the cab, and after it was full, gas flowed into the main tank. Can someone confirm this? The fuel lines running from the tank selector switch are only 5/16" which I can see really effecting the fill rate for the main tank.

 

Hi and welcome to FTZ. These are my thoughts without seeing your cab and chassis set up.
I doubt very much the filling of the tanks had any leveling effect between them. If there was a line hooked between the Bottom of each tank, yes they could level, like Big Rigs did with twin tanks on each side of the frame. In your situation, you would fill each tank and use the selector valve to choose the tank to draw from. The selector valve, MIGHT have a both tanks position to draw from. You F-350, 1969 would have had it's main tank in the cab behind the seat. Auxiliary tank would be chassis mounted and probably where Ford positioned it as an option, side of frame, back of frame. The camper mfg would choose the filler configuration. Maybe some others will give you more input and correct me if needed.
Cap

 

Thanks for answering. From what I've found, the camper special RV's were unique in the way that the main tank was also between the frame, because of the pass through (shown in attached pic) into the camper being where an in cab tank would go. I saw a diagram of the two tanks between the frame a while back but didn't save it (there's the hindsight thing). The selector valve was still on the truck when I got it but frozen up so I changed it out with one that has a solenoid and does it automatically when the other tank is selected. I'm going to be adding an in cab tank as the main tank though and found a diagram of the setup and located the parts shown for it through Dennis Carpenter. The diagram's just not real clear on the fill situation so I thought I'd ask. Thanks again.

#ad

 

Interesting truck, it looks like it had factory buckets, the piece of chrome in the picture was part or the carpet that covered the tank, pity it was cut. If you have a really weird left inner fender, you had the power pack option.
Likely the tanks were custom, but there was a 30 gallon unit mounted outside the frame, LH, on the M400 motor home chassis, also used on P series. I have the dealership binder for '72, and cannot find anything for the F350 other than the stock tanks as used in lighter trucks, but something may be hidden in there somewhere. Note that the tanks changed a little in , I think 1970? They got extra tubing.

 

The inner left fender is a little different than the one on my 67 F100 but not that much. This one came with the 360 2v, a C6, and a Dana 70 dually rear end with 410's. I've had it since last September and have rebuilt or replaced everything from the back forward (sent the transmission out for rebuild). Did a couple minor upgrades to the engine. Added a mild RV cam and changed the carb to a 4v. I'm building it to pull a 5th wheel and have another cab I plan on modifying and mounting to the back of the existing cab backwards, for a suicide door effect. Thanks for your input. I've learned a lot about this beast since buying it but I know there's a whole bunch more a don't know.

 

Fordification has a lot of factory data on these trucks, so you can decode the data plate, they even have the trim codes to determine if it was factory buckets. Also check Ford Heritage Vault, lots of factory publications there.
The 4.11 rear should work well, my '67 CS has a crazy low 456 rear, but if you like low, I have a '61 Mercury F350 tow truck which has 4.86!

 

Jim C, this build of yours sure does warrant pictures. Please send a few here and there, we'd love seeing it come together, Thank's, Cap

 

Thanks for the info. Many years ago, I helped a friend put 513's in the rear end of his 70 boss that had a nicely built 427. You couldn't reach out to touch the dash when he got on it!

 

Hey Cap, here's a few pics of the build so far. Since I don't have a facility to do a complete frame up build the way I would like to, I stripped the truck down to just the frame, cab, and front clip. After cleaning up the frame, spraying it with rust inhibitor, then coating it with spray on bed liner, I started putting it back together. The truck has just under 66k original miles on it and because it was parked on cement, it's very solid. However, because it sat outside in the often harsh Wisconsin weather, most of the mechanical stuff was frozen up. The engine turned over and ran after a little work, so that was a plus. Just put the exhaust on last week.

#ad


#ad


#ad


#ad


#ad

 

Thank You on all the pic's! Very Nice Work you doing. The Dual exhaust set up, your design or as the RV people did it?? Looks like she's sitting nose to nose with possibly your daily driver? Cap

 

Thanks Cap! The original exhaust was single ran down side. I wanted duals though but had to run both down the right side also, due to the auxiliary fuel tank on the left side. I used the old sand packed tube a torch method to bend the pipes. The other vehicle is my 67 F100 that's our secondary driver. I work from home though so I drive it every chance I get. 420hp 390GT with a C6, 9" rear end with 373 gears. My wife bought it for me in 2015 as a father's day gift thinking it was a Chevy. Though I owned a 70 F350 years before, that was the start of my transformation into a Ford guy.