knock knock

[Dune Country]

to my fellow N'sters

Pulled oil pump due to low pressure, had bushing pressed in,installed new pick up tube, installed pump & pan didn't touch anything else, started it up and there is a knock, sounds like a rod but isn't (pulled plug wires one at a time)it is loudest around the drain plug, unfortunately I did not side by side compare old and new pick up tubes. Is it possible that the new tube was "clocked" wrong when installed on the pump plate? Are the tolerances to a crank throw that tight? the pick did align up with the drain hole, oh and the oil pressure is great
any ideas

 

[Tall T]

Someone here had a similar experience a couple of months ago and it was the crank hitting the tube if I remember correctly and yes tolerances can be that close.

 

[Ken(Ark)]

(quoted from post at 12:30:31 04/06/15)
Someone here had a similar experience a couple of months ago and it was the crank hitting the tube if I remember correctly and yes tolerances can be that close.

His new drain plug and screen was 1/4" taller and pushed the tube into the crank .

 

[67Chevrolet]

Yes the clearance is very close. Its probably the crank hitting the pick up tube. Ive seen that exact same problem before. On my last 8n engine that I rebuilt I also replaced the oil pick up tube and it also hit the crank upon inspection, so i had to adjust or bend it so it would not hit, but also still line up with the oil drain plug. Luckily I had been warned about this by members here on this site, so I caught it while it was still on the engine stand. The pick up tube that I replaced on that engine had been brazed in several places by the previous owner, so I think this is a common problem. Good luck.

 

[POPGUN]

DC it was me crank nicking the P/U tube. It was my new drain plug. Fixed old drain plug and it
quit. I thought it was a rod at first till I pulled plug wires and my buddy said it not a rod
and said what was the last thing I did? Oil change, that was it new plug 1/4 of gobbered on
solder on top of screen .

 

[Charner MS]

Make sure you check the pick-up tube. Sometimes the crank impact will bread the weld at the pump.