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Check the oil filler tube to make swure it is not pushed down into block to far. Possible oil pick up float has broken ears (if it is a floater type).

Didn't Kev the webmaster have a knock problem like this about 6 months ago????

My problem was a out of adjustment solid lifter.

I'm going to ignore the slight tapping at idle for now, and write it off for the moment as lifter noise or fuel pump related. It's definitely different than the noise i get when the engine detonates.

I'm going to try running a clean line to the fuel pump and into a gas can on the floor in the passenger compartment. A fire extinguisher and we're off for a test drive. If it's starving for fuel because of a line issue or tank issue that should isolate it. If not, then i have to assume it's pump or carb related, correct?

Yes, running a secondary fuel source directly to the pump will remove the line and tank will eliminate them from the equation. Just make sure to have the vent open on the fuel can, and the windows rolled down.

And the fire extinguisher handy....sounds scary honestly! Have to try something to keep moving forward with it though.

Put a half full gas can in and ran some correct sized 3/8 clear vinyl line and warmed it up. Could still hear to ticking at idle, it just seems more pronounced hot. If you had the hood shut and weren't listening for it, you wouldn't notice it.

Used the stethoscope and listened in different areas but couldn't locate it other to say it's more forward on the motor than back.

Wouldn't think chain, it's a new timing chain. Still leaning towards lifter or fuel pump.

Anyways, after warming it up, went for a drive, and it still lost pressure. If you squeeze the line going into the carb you can see the needle bounce to like 1 psi, so there's something there but not much.

I did however see some clear air bubbles moving uphill towards the gas can after it was warmed up and i had no pressure! (up the line through the hood latch hole in the firewall)

It only took the pump 5 or 10 seconds to start pumping the air out of the line at idle cold, and the line had 2.5psi in it between pump and carb to start with, so it wasn't starving.

It warmed up on fast idle and then out we went. More spark knock at part throttle, let off or give it more and it goes away. I would think i'm just a little advanced on timing except when i got back no pressure again! And revving it in the driveway cold with pressure...no spark knock. Revving it in the driveway hot without pressure, spark knock.

Maybe the 50 pump won't work in the 53 motor (although it did for 2 tank fulls) or there's something wrong with the new pump?

Fred, do you guys notice any returns due to honest warranty issues and not someone messing it up when it comes to fuel pumps?

Edit: Also, spark must be strong. I have a set of the kanter braided wires with silicone (i believe) boots and pulling them off one by one to see if the knock/ticking changed (it didn't) netted my a couple nice shocks. I was using insulated needle nose plyer handles and making sure i wasn't touching any part of the car while removing them.

You ran the line directly to the fuel pump, and securely hose-clamped the line in place so no air could get sucked in?

I wonder if you have a bad/loose/obstructed check valve in the pump.

Yes, one piece line, clear, hose clamped to brass fitting on the pump.

Touching the pump, it was warm in a couple areas, but the bowl on the bottom was actually cool, and nowhere was it uncomfortable to touch the fuel pump.

Would that valve issue only manifest itself when warm? It seems to be moving some fuel while it's weak, as it doesn't stall. Just seemed lazy and didn't care about those air bubbles. When i started it cold it sucked the air RIGHT out of the line.

This may be helpful.

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Well i do know that 53 and 50 are different fuel pumps according to the numbers, but that doesn't necessarily mean they won't interchange.

I mean, the obvious thing to do is put an electric pump on to avoid the pre-warm up vapor lock i'm experiencing.

But jesting aside, i think i'm going to call up max merritt and talk about this and see what they say. Perhaps i need a 53 pump and that'd get rid of the light ticking, but i'm not sure about the pressure issue...why would the pump work for the first 5 minutes and then start having issues after that? You'd think if it's the wrong pump it wouldn't work correctly from the start.