Just got my Melling high volume oil pump in from TPIS and I am reading the paper that came with it. IT SAYS:

A NEW INTERMEDIATE SHAFT with a PINNED STEEL SLEVE MUST be used with this Oil Pump Application. DO NOT use a substitute.

What the f#%$ is this? Do I really need a different intermediate shaft for the pump than the stock LT1 one?

In case it matters, this is for a 383 93' LT1 motor.
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Next part. It also says the installed spring will allow equilibirum at approx. 70psi. and that not all engines are capable of this and to install the other spring that came with it for other engines. What about this, is the 70 psi figure ok?

 

Oh, and don't laugh, but how are you suppose to install the pickup onto the pump. I know a tack weld or a clamp can hold it once it is installed, but how do get it into the hole? :confused:

 

The stock coupling (sleeve) on the intermediate shaft is a plastic part. Most racers upgrade to a steel coupling. The guys at TPIS should be able to explain this and supply the appropriate part. My guess is that the HV pump puts more strain on the coupling, so the pump manufacturers are being cautious.

Similarly, racers often use the Chevy 70 psi spring in the oil pump, whereas the stock spring is good for 45 psi or so at RPM hot. Especially when cold, 70 psi can blow off cheap oil filters, or find worn seals. In a well built engine it is not a problem.

Installing the pump pickup is usually done with a specialized tool that aligns the tube and allows one to exert force without crushing the tube. As you mentioned, after positioning, the tube is brazed for retention.

Real question would be why a HV pump is needed? Most racers clean up the pump internally to minimize restriction and reduce cavitation, but other than adding the 70 psi spring, the pump is generally felt to be OK as is. Larger gears for higher volume are not generally felt to be necessary from a lubrication standpoint, and cost HP to drive. At least that's what most of the builders say. If the pump you chose is merely blueprinted and relieved, that's work you don't have to do yourself.

Chevy, Lingenfelter, and Smokey Yunick all have excellent engine build-up books that discuss in detail the oil pump among other topics.
Hope this helps.

 

You can install the pickup without the specialzed tool if you're careful.

If you look at the pickup you'll see a raised area near the end which is designed as a stop to let you know when the pickup tube is fully inserted into the pump. You can use that raised area strike it with a small hammer and blunt chisel, going from side to side, top to bottom, and the tube will go in.

I have, in the past, placed the oil pump in a bench vise with pieces of 2"x4" on either side of the pump to hold it steady. I've even removed the bottom plate - four bolts - and put only that into the vice (protected of course).

Tap a little at a time.

If you have a machine shop near-by, I'm sure they have the specialized tool and will do it, sometimes for free (if you've done business with them before) or for about $10.

Most guys have the tube welded to the pump body. If you choose to do so, be sure to remove the pressure spring so the heat from the welding doesn't weaken it.

Other guys just pin the tube rather than weld it. I think the welding method is better since there won't be that "pin" in the oil flow path. The machine shop can do that too.

High Volume (HV), High Pressure (HP), HV/HP, standard: differing views have been going on about this as long as I can remember. Depends on who you talk to.

Hope this helps.

Jake

 

Even easier than the hammer and chisel, I use a curved jaw set of vice grips on the tube of the pick up. I don't clamp them tight enough to really grip the tube, but the bulge in the tube stops them from moving. Then, I simply tap on the vice grips to drive the pick up tube into the pump.

You DO need the steel sleeved drive shaft. And like Jake said, don't braze or weld the pick up to the pump, without first removing the relief spring. Good luck, and...

RACE ON!!!

 

Foudn the tool for rent at Autozone and the shaft at Checkers Auto Parts. I ended having to buy two shafts because the first one fell out the compartment on my motorcycle on the way home :mad But I guess it was only a 6 dollar part.

Thanks for the info about the spring, I wouldn't have thought of it.

 

To install the pickup...you could just take a 5 pound mallet and tap on the curved portion of the tube with a rag minimizing the damage...like I did. :)

I tried using the open ended wrench on the lip, but that didn't fly.

Of course if you get overzealous you could crack the pipe or distort the pickup all together.

As far as welding...I favor the pickups that you can bolt to the pump...eliminates the heat factor...

:)

 

Hey! Another biker who picks up parks on the two wheeler.

I did the same thing this past summer, only it was my son's air bottle for his paint ball gun. Destroyed the threads on the bottle, but I bought a new screw-on fitting for $10 and he was out shooting again.

Jake

 

I had the exact same questions and was going to post but left for holiday vacation and would be away from a pc.

Sounds like I will be getting the new shaft.

Any more tips on the pressure though? I bought a M55HV. I thought I was getting a high volume unit, not the high volume high pressure. From the sheet with the pump it appears to be set up for high pressure also, and you can change to the provided spring for standard pressure. Is high pressure needed? Or should I switch to the lower pressure spring?

 

Responses will be all over the map on this one. Some like everything standard, other HV, still others go with HP but standard volume and the last group likes both HV and HP.

I run HV with a 3/4" pickup tube and HP spring with light weight oil.

Jake