Any reason NOT to use my stock oil pump?

DDS · 11-04-2001, 04:55 PM

I'm working through my 2056cc rebuild and ready to order the last of my required parts - the engine will have Web 86a cam, 96mm NPR pistons and cyls, ported heads with 44 and 36mm valves and Weber 42 DCNFs.
I haven't resolved what to do about ignition or oil pump - any reason not to use the stock pump?
TIA, Dave

Jake Raby · 11-04-2001, 05:54 PM

It is hard to find a stock pump that will pass the wear checks, however some of them will. If yours checks out, and you HAVE NOT done any rod modifications, and are running up to .013 rod side clearance yiou should be fine, as long as super high RPM is not your desire.

We mostly used modified Type I pumps in our engines, but it does take some clearance work.

DDS · 11-05-2001, 03:19 AM

Thanks as always Jake. I'll check the pump - any recommendations on the modified version? IIRC your video discusses the clearancing. THe rod clearance was within the tolerances indicated in my Haynes manual and Wilson's book, but I don't remember the value - I'll measure when I get the crank back. WRT RPM - I don't really know what to expect, though certainly not super high. I'm adding a willing cam, rocker arm spacers and stiffer (single) springs so 6000 RPM redline might be reasonable. Thoughts?
Thanks.

jabez · 11-06-2001, 08:55 AM

There was a thread a while back on this. Do a search on oil pumps on this BBS and you'll find more information than you can shake a stick at.

SteveStromberg · 11-06-2001, 09:03 AM

I just built a motor with a NEW type 4 oil pump I cut the groove in the rods just like I always do. I am getting a flickering oil light at 500 rpm. I am going to pull the New stock pump and replace it with a 30mm melling for more volume at Idle.My advice is the same as Jakes, Stone stock is okay with the stock pump but for a moded motor use a larger pump. Steve

[This message has been edited by SteveStromberg (edited 11-07-2001).]

DDS · 11-06-2001, 06:40 PM

Thanks guys, I'll search as well. Haven't done the wear checks but it sounds as if a new pump might be wise anyway.

Doug M · 11-07-2001, 05:16 AM

I have used the type 4 pumps from CB performance on 2 engines with good luck. They are almost too cheap , $25.
Doug

Jake Raby · 11-07-2001, 07:17 AM

Tear into that CB pump and check it out after about 3,000 miles....But don't do it if you don't wanna get scared to death!

914GOD · 11-07-2001, 07:28 AM

Jake,

I noticed on your site some of your engines come with Melling pumps. Is that a type IV Melling, or do they make a type I?

For that matter, who likes the type IV melling, or is it a POS?

Sean

Pillow · 11-07-2001, 07:36 AM

The CB pump is too cheap... I run a Maxi3 full-flow pump on my T1 engine for my bus and just tore it apart on Sunday to switch out cams... The gears are already showing wear after about 1500 miles. I was very surprised since I have seen stock T1 pumps with 100,000 look about the same. I will keep the Maxi3 for now and hope to get a T4 motor in there before the pump dies.

After tearing down about 4-5 stock T4 oil pumps it is amazing to see how well they hold up. Every one I have seen is within specs to reuse.

Granted if you are going hogwild on the engine splurge to something more HD.

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Adrian Pillow
1979 911 SC
1966 VW Microbus
PCA - Peachstate Region

Dave at Pelican Parts · Dave at Pelican Parts's Garage

If your oil light flickers on at <500 RPM, it's not because the oil pump isn't working. It's because the idle RPMs are too darned low.

Put the idle back to spec (900 +-50) and watch the light go out.

--DD

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Pelican Parts 914 Tech Support

A few pics of my car: http://www.pelicanparts.com/gallery/Dave_Darling

DDS · 11-07-2001, 04:15 PM

Interesting - Jake, to clarify, does 'modified' mean 'clearanced' when referring to T1 pumps? In "Hotrodding VW engines" the author refers to a method of blueprinting the stock (T1) oil pump. If my T4 is less than perfect, maybe that's the way to go.
It sounds like oil pumps aren't astronomically priced, so I would like to make sure I have the best reasonable option -doesn't seem like a good place to save money.
Any comments on the Melling?
BTW I searched and must have missed that thread.

Doug M · 11-08-2001, 07:24 AM

Ok Jake you got me worried so I checked out my spare eng. with the CB pump. I didnt find any significant wear on the pump housing, cover or gears.Is the gears that wear the most or the housing?
I dont think I will be using any more $25 CB pumps anymore.
Maybe it is the sand oil mix that the buggies use that kills them.
Doug