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Project "RESPAWN" - 1972 K5 Blazer

Cool stuff here!
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If you pop out for comments like this you should at least stop by your thread and say hi, nothing to report.
It's only fair
I've got some time off next week, and it looks like it's been about 2.5 years since the last update.... let me see what I can do to provide updates on the major milestones.
 
Today was trim hole day! There was one set of 16 and another set of 6 screw holes on the windshield frame. I believe the soft tops come with a 16 and 6 hole attachment option so 2 past owners probably did that.

 
Not going to put the stock trim back on, probably going with the 67 truck style eventually.
Just so we are on the same page, like this.

tan5.jpg
 
Next up, find out why this thing has no power and just bogs down at WOT.
I put a fuel pressure gauge on it and it's pulling 8 PSI at idle, WOT while driving it stays at 8 PSI.
Went back and pinched the return line, it moved up to 12 PSI, WOT while driving it goes down to 10 PSI.

Think it's the fuel pressure regulator?
 
I would think weak pump, because if you restricted the return line completely, it should be able to go higher. I put a 15 psi regulator on a TBI truck without changing the pump. It hit 15 + psi no problem.
 
Also, it doesn't hold pressure when i turn the motor off, goes to 0 pressure within a few seconds, wouldn't that be a symptom of a bad regulator allowing the fuel to drain back to the tank?
 
Fuel pressure bleeding off could be the regulator, but not always since there should be a check valve in the pump that will help retain fuel in the line. It could be one or both of the injectors bleeding the pressure off too or the check valve is not holding fuel in the line. Though either instance should be giving you an extended crank or multiple tries at cranking before it gets fuel.
 
Fuel pressure bleeding off could be the regulator, but not always since there should be a check valve in the pump that will help retain fuel in the line. It could be one or both of the injectors bleeding the pressure off too or the check valve is not holding fuel in the line. Though either instance should be giving you an extended crank or multiple tries at cranking before it gets fuel.
Yeah, could very well be a combo of both, even though it's more expensive I might start with a new TBI unit, that way I get new injectors and regulator, sensors etc. all at once. More expensive but easier than dropping the tank and go from there.
 
Even with the pump only putting out 8 PSI?
Very possible. Honestly, I would expect to see the rubber jumper hose from pump to module split. That would explain the low psi and the pressure drop after shutoff. I wanna say the last three out of four pumps I pulled had that issue. Obviously I can’t gaurantee that guess, but I’ve seen that 99% more times than the tbi unit.
 
I’ve had that hose split on me after a month and a couple hundred miles. Nothing is built right these days.
 
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