Carburetor fuel system plumbing

[JMortensen]

Got a suggestion on another forum to hook the NPT fitting on the pump to the NPT fitting on the filter. I went and looked and sure enough I had the fitting and adapter necessary to do this. Hooking them both together directly gives me room to get the other filter on the side as well. Need a union and a 90 and I do the hard line stuff. Thinking I should hook the hard line directly to the filter and get rid of the soft line from the filter to the floor, will look at how difficult that bending will be. Should be pretty easy.

[jt1]

If you mount them directly to each other, you need to fab a common mounting plate so you don't stress the fitting that connects them. You also need to make it so you can R&R them as a unit. A stainless fitting between the pump and filter is probably a good idea, since brass works hardens pretty quickly.

 

A friend had a hard coupled pump and filter bolted to a sheetmetal panel. Somehow there was enough deflection to crack the brass fitting at one of the threads, and soak the rear of the car with gas. Luckily we did not have ignition/liftoff, but it had a lot of potential.

 

jt

[JMortensen]

Hmm... I have a stainless 1/4 NPT union into a brass adapter on the filter. I suppose I could go get a stainless adapter for the NPT fitting. I guess the trouble might be getting the brass one out of the filter now.

 

The pump, I'm sure you'll remember, is rubber mounted on 3 vertical studs. I shimmed out the pump bracket so there is less strain on the rubber mounts, but there still was a little deflection in the rubber when I tightened it down. If necessary I think making a mount to solid mount the pump wouldn't be too difficult. Just drill the holes the same size as the studs on top and bolt it solid that way. I suppose another solution would be to go to a smaller filter that might be more flexible in where it gets mounted. I chose this one simply because a friend of mine had used it in the past.

 

Thoughts?

[JMortensen]

Went back out and started messing around with that big ass filter again, that sucker just doesn't fit anywhere. SO SCREW IT. Bought another small filter, will mount in front of cell. The pump and pre-filter will be on the side of the cell. Hard line will attach from the 2nd filter and run up to the firewall. Not worth taking a chance on a fuel leak to get a 10 micron filter in there instead of a 40 micron.

 

Anyone want to buy an unused HPG-1 filter???

[jt1]

The Fram filters are a nice piece, they do a good job and are widely used in the circle track world. They are sort of bulky and heavy.

 

What size cell are you using?

 

jt

[JMortensen]

12 gal, but it's nosed down 7 degrees, so it probably holds about 8 gal in this config.

[JMortensen]

Here's what I came up with from the cell to the engine compartment. Will need to get the engine installed before I go any further.

 

Hose along trans tunnel, crosses over to right side to come up on the correct side of the engine compartment.

 

Ended up needing the soft line in the back, wasn't enough room to route the hard line without removing all the suspension and I didn't want to do that.

 

Hard line crosses over the brake line. Every place where this happens I have zip ties around both lines that are hooked together. This holds them together without letting the lines touch or rub.

 

Here is the cell to the first filter, to the pump, to the second filter in front of the cell.

 

Someday I might incorporate a diffuser into the back, so I tilted the cell 7 degrees and installed it backwards so that the pickup is at the front corner instead of the back corner.