Racey
Maxwell Smart-Ass
- Joined
- Sep 18, 2007
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A good friend brought this pickup to DaveH to check out some EFI related issues, The original shop had hidden all the injectors inside the blower hat to hide them, which was a cool idea, but just had some bad execution and the entire setup was leaking fuel. This stuff is like 10+ years old probably now, so we fixed it all.
So they had this rail setup hanging inside the hat, bulkhead fittings with silicone:
Rails were all tapped with NPT pipe fittings, i always say the same thing when i see this, pipe fittings are for your sprinklers not your fuel system, you can see how the tapered fitting has blown out the thin wall of the rail:
the correct fitting is an AN ORB but not that many people take the time to do them because it requires properly porting the rail for the oring and proper compression of it, this requires special cutters, or special fixtures (i have both).
Also these inlet and outlet NPT fittings run in at 45 degree angles, if you know anything about how pipe threads seal, this is very bad ju ju.
Pipe threads required several uninterrupted threads to create a sealing mate, this entire thing was leaking like a soaker hose.
I scrapped all of it and started from scratch, started by machining out the entire rear of the blower hat, and machining a separate piece of billet with all proper ORB fittings, O-ring seals on the fasteners, and o-ring seals on the injector driver connector, then welding it into the hat:
The brass tubes act as alignment dowels for the fuel, and have o-ring grooves on the outside that face seal to the newly machined fuel rail, which is actually a full billet fuel manifold, the 4 bolt holes are also o-ring sealed so that no air leakage will occur either:
The above piece that is welded in mates to this newly machined rail/manifold:
Mating end:
It's also a full flow through, so fuel goes in one end, and out the other as opposed to two dead end rails, which could cause vapor locking issues, the transfer gallery, connected the left and right manifolds is ORB capped and safety wired:
Injector wiring is all hermetically sealed in a fuel safe shrink wrap, including the connectors, custom made by the injector supplier this way for us. All ready to be sealed into the bulkhead connector here:
Adel clamps and lots more safety wire everywhere, this old blower casting was not totally symmetrical, and was probably hand shaped, so even though the welded in manifold is visually in the center at the back of the hat, it's actually all slightly offset internally, you can see the injector hold downs are a little different left to right. They are also o-ring sealed and supported with cross bolts from the exterior of the hat.
So they had this rail setup hanging inside the hat, bulkhead fittings with silicone:
Rails were all tapped with NPT pipe fittings, i always say the same thing when i see this, pipe fittings are for your sprinklers not your fuel system, you can see how the tapered fitting has blown out the thin wall of the rail:
the correct fitting is an AN ORB but not that many people take the time to do them because it requires properly porting the rail for the oring and proper compression of it, this requires special cutters, or special fixtures (i have both).
Also these inlet and outlet NPT fittings run in at 45 degree angles, if you know anything about how pipe threads seal, this is very bad ju ju.
Pipe threads required several uninterrupted threads to create a sealing mate, this entire thing was leaking like a soaker hose.
I scrapped all of it and started from scratch, started by machining out the entire rear of the blower hat, and machining a separate piece of billet with all proper ORB fittings, O-ring seals on the fasteners, and o-ring seals on the injector driver connector, then welding it into the hat:
The brass tubes act as alignment dowels for the fuel, and have o-ring grooves on the outside that face seal to the newly machined fuel rail, which is actually a full billet fuel manifold, the 4 bolt holes are also o-ring sealed so that no air leakage will occur either:
The above piece that is welded in mates to this newly machined rail/manifold:
Mating end:
It's also a full flow through, so fuel goes in one end, and out the other as opposed to two dead end rails, which could cause vapor locking issues, the transfer gallery, connected the left and right manifolds is ORB capped and safety wired:
Injector wiring is all hermetically sealed in a fuel safe shrink wrap, including the connectors, custom made by the injector supplier this way for us. All ready to be sealed into the bulkhead connector here:
Adel clamps and lots more safety wire everywhere, this old blower casting was not totally symmetrical, and was probably hand shaped, so even though the welded in manifold is visually in the center at the back of the hat, it's actually all slightly offset internally, you can see the injector hold downs are a little different left to right. They are also o-ring sealed and supported with cross bolts from the exterior of the hat.
