Hello!
Alright so my boyfriend and I are trying to figure this one out and it has us scratching our heads. He's got a 67 Dart with a 78 318/904 combo. Budget junkyard rebuild, new seals and bearings with a 340-esque cam. Mechanical fuel pump and stock tank.
He's been driving it as is for a few months and it's been great. We decided to head down to Woodburn and that was a 2.5 hour drive down the 5. When we arrived and waiting in line to enter, his Dart dies. He struggles to get it started and it does this multiple times before we parked. It was a real struggle going into traffic on the way home. We put a heat sleeve on the fuel line by the header tube, tied it further away, and changed the in line fuel filter. We noticed it was bubbling into the filter and it was barely filling up. It still had issues but we managed to all get home.
It's completely fine when cold. The filter fills up. He drives it around for approximately 15-20 minutes with 0 issues. We've gone around the neighborhood multiple times, stopping and all that. We've noticed the filter ever so slowly loses its fuel level over the course of maybe half an hour to 45 minutes. It eventually gets to the point where there's not enough fuel in the filter and it sputters, backfires, and dies: but dies only in gear. Hard to start.
He's done multiple things and we're still left confused. Here's what's been done :
-New fuel tank (he had it already)
-Blew out fuel lines with compressed air and some brake cleaner (nothing in there)
-New fuel pump installed, twice. (no change)
-Changed the fuel filter
-Bent the hard fuel line even further away from the header
-Cleaned out the carb (650 cfm AVS. Had some dirt in the bottom but filters were okay)
-Got a new vented gas cap
-Blocked off the vent on the gas tank
-Ran the car with the mechanical fuel pump but ran it from a gas can. While we didn't wait to see if it stalled completely, the fuel filter did not fill up or change. It began to run a little rough in gear and we shut it down. That tells me it's nothing to do upstream of the fuel pump and that leaves the fuel pump, eccentric, lines, and carb.
He's got it to stop bubbling into the filter (maybe solved a boiling issue), but it's barely pumping into there. My Dart has the filter almost full the entire time (also mechanical). The odd thing is the little fuel pressure gauge consistently reads 6 psi, even when there's almost no fuel in the fuel filter that's down stream of it.
Could the used fuel eccentric have failed? We can see its got a bit of wear but he hasn't torn the front part of the engine to remove it. What else can we test? Any help is appreciated. He may chime in on here to answer questions as well. (
@Byron Gray).
