So I got a new oil pump and pickup tube (screen) and went to assemble today and ran into an issue. Both parts from Sealed Engine, 224-43469 and 224-14258. I know the pickup tube is supposed to be an interference fit into the pump (0.006" interference I think?) but not until halfway down the hole where the ID reduces. I tried assembling today and I couldn't get it started. Busted out the calipers and the OD of the tube is dead on at 0.750", but the ID of the hole in the pump measured 0.737" in the first half and 0.730" in the last half. No way in Hades this is going to fit, right? The pump must have been machined incorrectly! I would expect it to measure around 0.750" and 0.744".
Yep. An extra .013 is never going in if the fit is.0006.
A couple of things to consider.
Did you check the tube for out of round.
Did you check it for burrs on the end.
Did you try to force it and push a burr on the end or twist it out of round.
How good are your calipers? When you check OD with a caliper you use the flats of the jaw or the inside taper of the jaw.
When you check ID with a cailper you use the outside points of the jaw.
And any little bent or worn part will seriously screw up your measurements.
Even the best caliper is only reliable to plus or minus .001.
And only if they are calibrated every month and kept in a little velvet lined box
with a mouse trap so nobody can touch them.
So, make sure you arent chasing your tail due to bent tips on your caliper when you check the ID of the hole.
.0006 clear is micrometer time.
Way beyond what any caliper will tell you inside or outside.
But, .013 is a friggen country mile in the precision world and that will never go in.
Check for burrs, check for out of round.
Make sure you didnt push a burr into the hole or spall up the whole by trying to twist it in.
And you might just be screwed by chinese manufacturing.
