Type 4 oil pump rebuild, Comparison of OEM vs. Samba CNC pump Options

[Superhawk996]

Playing with the idea of what it will take to rebuild a type 4 pump.

The pump that came out of my 2.0L engine is trashed from pumping rust. Both the gears and the housings are seriously scored.



I figured I'd roll the dice and see what might be on Ebay. Took a gamble and bought a used pump hoping I might get some core parts that are useful.



I did end up with a good housing outer. However, the gears are pitted and it the inner housing plate either has a serious casting flaw, or some sort of galvanic corrosion that pitted it. I always struggle with this kind of thing. It really would have minimal effect on the pump and it probably worked OK for a lot of years. However, I'd just like to know that it is perfect going before going into a engine.





It looks like new inner plates are available but at a cost of $150+.

I decided that since I have a donor "scrap" pump, I have nothing to lose by experimenting with machining it.

[Valy]

@Superhawk996
It works well, no issues so far but I'm not driving it much.
Just make sure you get a pump that has the right diameter.
The iron ones like Melling are too small and expand at a different rate than aluminum. Even with the O ring, there will be a lot of bypass between in and out and a lot of pressure on the outside gasket that may eventually fail.
Make sure the mounting surface is flat (the 2 case halfs) and always add some sealer to the gasket. Use a thick gasket too. Look at the gasket template in my signature. I made my own gaskets to be sure.
Don't over torque the bolts if you don't want leaks and use big washers.