correct oil pump number question
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From: Bradenton Florida
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correct oil pump number question
I am in the process of ordering a new oil pump and shaft rod. I am changing the oil pan gasket so I figured now is a good time to change the oil pump also. I have a 1994 C-4 LT-1 P-code Vette basic hatch model. I originally thought that the GM replacement was part #93427692. But as I research, other vendors are giving different numbers.
So to be on the side of caution, what I need to know from the pro's is What is the correct oil pump part number, shaft number, and oil pick-up tube number. Also would a high volume pump be overkill or is there a definate advantage. I do have the 94 GM manuals but can not find the part numbers. I am hoping to order today.
Thanks
Woody
So to be on the side of caution, what I need to know from the pro's is What is the correct oil pump part number, shaft number, and oil pick-up tube number. Also would a high volume pump be overkill or is there a definate advantage. I do have the 94 GM manuals but can not find the part numbers. I am hoping to order today.
Thanks
Woody
Last edited by woody3882; Feb 9, 2017 at 11:25 AM.
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Your original could have I believe a .620 tube or a .742 tube and you need to just decide which you might prefer and buy pump & screen to match and for the Corvette pan. I believe it's generally assumed that the .742 is a higher volume piece. GM# 12558283 is the later LT1/4 pump that's OE and 12550106 the match for that in a Corvette pan. Melling service for that pump I believe is likely a M155,
The M55 reference I believe is a 620 tube pick-up I believe that's the considered differences when you compare to OE.
Years ago we only used Melling - has that changed today? I've no idea. Ask maybe a couple local builders that you might trust. Shaft and retainer just the same ole SBC stuff.
The M55 reference I believe is a 620 tube pick-up I believe that's the considered differences when you compare to OE.
Years ago we only used Melling - has that changed today? I've no idea. Ask maybe a couple local builders that you might trust. Shaft and retainer just the same ole SBC stuff.
Melting Slicks
Joined: Jan 2009
Posts: 3,482
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From: folsom california
okay, been there done that. first be aware that the corvette pan is a nominal 7 inches deep; 6&7/8ths inch plus gasket thickness; so there ain't a lot of pump and pump pickup combos that will fit.
definitely get a pump and pickup recommended for your year...don't try any I think it'll work...unless you want to modify pan and or pickup.
the LT engines use a conventional small block pump, but with a 3/4 inch pickup tube...earlier small blocks used a smaller tube.
I'm not gonna start a pissing match on the subject of standard versus high volume pumps, suffice to say I use a high volume pump, but it's a close fit, the extended pump housing may or may not interfere with the pan...yes it is that close..so get a pump and a pickup designed for your corvette.
Have someone tack weld the pickup to the pump body...it's not an old mechanic's tale, the pump pickup will loosen with time ... this I know.
You have an LT engine, a weak point is the oil pump stub shaft drive located in the lifter valley...google it.
The oil pump drive shaft is the same as any small block oil pump drive shaft (except the 400 ci engines which used a shaft with a reduced outside diameter).
definitely get a pump and pickup recommended for your year...don't try any I think it'll work...unless you want to modify pan and or pickup.
the LT engines use a conventional small block pump, but with a 3/4 inch pickup tube...earlier small blocks used a smaller tube.
I'm not gonna start a pissing match on the subject of standard versus high volume pumps, suffice to say I use a high volume pump, but it's a close fit, the extended pump housing may or may not interfere with the pan...yes it is that close..so get a pump and a pickup designed for your corvette.
Have someone tack weld the pickup to the pump body...it's not an old mechanic's tale, the pump pickup will loosen with time ... this I know.
You have an LT engine, a weak point is the oil pump stub shaft drive located in the lifter valley...google it.
The oil pump drive shaft is the same as any small block oil pump drive shaft (except the 400 ci engines which used a shaft with a reduced outside diameter).
Last edited by mtwoolford; Feb 10, 2017 at 02:09 PM.
