73 340 oil pump

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Originalowner73 340duster

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Wondering what the good oil pump to use since it started to squeal and oil light was flickering and gotta drop oil pan anyway.motor I believe is stock with headers and purp cam...will want to reuse when I rebuild original motor with good street hp
 
On my 340 , I used a Melling high volume pump M-72HV and a Canton oil filter plate 22-575. Great results
 
Melling is the go-to performance aftermarket brand
no offshore junk- the drives strip out and other bad things happen
that said
pull any new part apart and clean and check, check that the relief piston moves freely
quality new drive with hardened tip is recommended (by me IMHO)
old ones can round off or snap
your clearances have opened up which is why hv was recommended
you may not need it but hard to tell unless you had a mech pressure gauge and saw pressure dropping
all your quality mail order companies have the melling pump
 
Melling is the go-to performance aftermarket brand
no offshore junk- the drives strip out and other bad things happen
that said
pull any new part apart and clean and check, check that the relief piston moves freely
quality new drive with hardened tip is recommended (by me IMHO)
old ones can round off or snap
your clearances have opened up which is why hv was recommended
you may not need it but hard to tell unless you had a mech pressure gauge and saw pressure dropping
all your quality mail order companies have the melling pump
My original 340 has hv pump but not sure in this one ..it just started to squeal one house away..but on last drive oil light was flickering..so maybe it just has a blockage in pick up and I could possibly emery the inside if not scared up ..
 
No, no, no... don't use abrasive inside the pump to smooth things out! That will just open up the internal clearances and the pump flow/pressure will drop like a rock! Just replace it... they are not expensive.

A squeal would be more likely a belt or pump. A squeal from the oiled internal parts of the engine pretty much means a badly damaged bearing or other part seizing up, and should not be run anymore without finding and correcting. I doubt that replacing the oil pump will fix an oiled part of the engine that is actually squealing.
 
No, no, no... don't use abrasive inside the pump to smooth things out! That will just open up the internal clearances and the pump flow/pressure will drop like a rock! Just replace it... they are not expensive.

A squeal would be more likely a belt or pump. A squeal from the oiled internal parts of the engine pretty much means a badly damaged bearing or other part seizing up, and should not be run anymore without finding and correcting. I doubt that replacing the oil pump will fix an oiled part of the engine that is actually squealing.
Thank you. I was hoping someone caught that. Squealing usually means a spun bearing. You may be looking at a overhaul.
 
Every time I heard that squeal from inside the pan, it was a seizing rod bearing. But don't worry,it goes away after a a minute or two.Then followed be the dreaded rod knock.

Each time it began, was after a spirited romp, with a low oil level. My last engine now wears a 7 quart pan, and I did the oiling mods; and now she is happy to go 7000 whenever.
So, yeah, I agree; it's at least crank inspection time. If still at the squealing stage, you may be able to get away with just a lil polish,and replacing the probably spun bearing, on probably #1 crank throw; or possibly #3. I only got a minute or so warning at idle, then the crank locked up and she stalled.
 
I've run a fine bottle brush through the pressure relief , flat sanded the housings with went sandpaper to reduce clearance and rounded the ports
ya gotta be careful
we also ran blueprinted non HV pumps in stock and heads up classes to reduce pumping losses

biggest change was to run a remote oil pressure relief at the front of the block
with a HP spring at the pump
keeps the oil from going around in circles and reduced foam, air entrapment
you got the correct suggestions above- pull the pan and check your front rod bearings then go from there
 
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