V-band clamp for GM fuel pump

[WHO1DMC]

I never had to remove the stud, it sits next to the pump and doesn't interfere at all.

I didn't remove mine and had no problems. I got my pump from DMCH and I don't remember it even being in the instructions.




Dave B.

[Bitsyncmaster]

Attachment 71554

Look at this photo of the DMCH pump. Probably if the pump had the flat side on the rear it would clear. Now is that pump sitting rotated how it has to be to clear the closing plate?

[Bitsyncmaster]

Here is what I have designed right now. Still always thinking about changes. But it looks like this will work. Just a 3D printed ring with 4 holes to press in 8-32 rivet nuts. This ring sits a little below that ridge on the tank so my plan is just to hot glue at that ridge so the ring can't pull up.

I plan to make a top ring out of aluminum or steel that presses the pump down. Could even just use fender washers.

I will position it so one screw is between the two fuel pipes, then the others should also clear.

I was thinking of making a thin ring of metal that would use a regular hose clamp to hold it onto the tank. But I don't think there is enough room for that hose clamp.

As always, suggestions or ideas always welcome.

[82DMC12]

I have the DPI Delphi pump and the stud is a non-issue. it sits under the pump in a sort of recess if I recall.

[Bitsyncmaster]

Here is the finished clamp installed. It should give you a little more clearance since the pump is clamped all the way down.

[Bitsyncmaster]

I just thought of another way to do the clamp. Could probably get enough flex with the 3D printed ring, so cut a slot so you can clamp it under the ridge. Could probably use a normal hose clamp for that.

[Bitsyncmaster]

I just thought of another way to do the clamp. Could probably get enough flex with the 3D printed ring, so cut a slot so you can clamp it under the ridge. Could probably use a normal hose clamp for that.

I'm convinced this is the way to go. It will wait till I get a chance to replace my glued one. I ordered at T- bolt clamp the for the new one and I have a new 3D printed ring ready to go.

I never stop trying to perfect things.

[Bitsyncmaster]

I 3D printed the top ring at 0.125" thick and I think it will be strong enough rather then make one in metal. I will look if I can make it thicker when I rework my original attempt. These are printed with PLA+ which I think will flex enough to use the hose clamp method. I may try printing in ABS just to see how that works. I could print them with resin but that results in very brittle parts.

[iflights]

Dave, thank you for the continued thought leadership. I have a GM pump with V-clamp, but have never been confident its fully pushed down. My pump avoids the stud but I cannot close the access panel. A previous "GM style" pump was in place previously and allowed the access panel to close. I like the solution you are outlining.

[Bitsyncmaster]

I printed that top plate with ABS. Testing both, it looks like the ABS is very slightly more flexible than PLA. I haven't done a break test yet but they say ABS is stronger.

I did however think of a change I need to do on my design. I need to have the lower ring ID the size of the tank neck, less the ridge. Therefor you make a cut in the ring and expand it over the ridge to install. Have to do that so the screw holes in the top ring will line up. If you were compressing the ring that would change the screw holes a little. I don't think you need much for the "hose clamp". This new change will almost stay put without a clamp.

All this needs to wait till I get time to pull my fuel pump again. So I can measure the exact OD of the tank neck less that ridge.