bison
Well-Known Member
There is actually no need to cut it off,Its just pressed in.i clamped the old barb in the vice and tapped the housing off it with punch and hammer.Howdy, All...
First, I cut the old barb off with a Dremel tool. Seemed to me easier than a hacksaw.I found a #4ORB to 3/8 barb in one piece; it's made by Brennan and available through industrial hose and pipe suppliers. I bought two; 2.63 each plus shipping. Here is the Brennan spec page:
http://www.brennaninc.com/ProductDisplay.asp?pg=productdisplay&item=4604-06-04-O
Thanks to all of you who blazed the trail; without you I wouldn't have known I needed a #4ORB!!
Drilled the filter housing out; the #4 thread (7/16-20) takes a 25/64 drill. NOTE: you DON'T need to drill the big hole all the way through to the fuel port in the center; you just need to drill it deep enough to tap the length of the threads on the fitting. Then you can drill the .250 fuel hole (discussed elsewhere) all the way to the fuel port in the center of the housing. As mentioned in other postings, measure the depth, then mark your drill with a ziptie...you DON'T want to drill into the center hub of the fuel housing. I used grease in the drill flutes to keep as many metal chips as possible from falling in the hole. I tapped the hole with a bottom tap, so it wouldn't project too far into the hole. The metal was so soft, it was easy to start the tap.
With a 1/2" drill, I created a countersink in the filter housing, to hold the O-ring. The metal of the filter housing is very soft; you don't need to press very hard or spin the drill very fast. You don't want to countersink too "deep;" you want the O-ring to have some "squish." If you try to squish it between two flat surfaces, it can be forced outwards and you will have no seal. You need that bevel to keep the seal in place. Viton O-rings, of course.
I also drilled out the new fittings a little, because the hole on the #4 end is smaller than .250. The hole in the barb is about 1/32" larger than .250, so that is the drill I used; the barb hole acted as a guide for the drill.
The rest is pretty straightforward; the new #4 fittings fit perfectly into the IP fitting.
--Clipper