225 Oil Pump Adapter Wear

That looks fairly scored ( if not bad they can sometimes be polished out) Melling makes a thrust plate that provides a new wear surface. Get a new oil pump while you are it and make sure it is correctly shimmed and packed with petroleum jelly before reinstalled. https://shop.advanceautoparts.com/p/melling-oil-pump-thrust-plate-kit-p-20i/5681014-P

 

Use the Melling , like Rich says . that's the trick.

 

With the AMC oil pumps, clearance between the cavity and the gears, and especially the end clearance of the gears with the oil filter adapter (that thing you show), makes more difference than the swirls on the cover. You can lap the adapter to remove the swirls. I expect your TSM has a spec for the end clearance, with the gasket in place. End clearance is reduced by lapping the timing cover, or using a special thinner gasket. There should be something on the Buick sites about this - the AMC sites cover it, as does the AMC TSM.

 

I agree with using the Melling pump kit. The adapter can be lapped using a flat piece of glass with sandpaper and wet sanding. I start with 500 grit and end with 1000 grit. Take your time and change directions frequently to keep the lapped my equal as possible. Make sure to thoroughly clean all passages when done.

 

We used the steel thrust plate on the '66 when we did it's pump and relief springs. It had similar wear. The plate came with new longer not slotted machine screws. I felt like it was a good idea.

Here Is what the timing cover looked like
20200510_150150 by Joe with a jeep, on Flickr

 

Follow the instructions, no way to know if your spring was an original. Your pump is packed correctly.

 

The spring regulates the max pressure.
It is easily accessible.
Replace the spring with either one you want, start the engine, and observe the pressure @2000RPM. If it isn't around 40PSI (+or-), try the longer/stiffer spring. If it is over 50PSI, I would go the other way.
Personally, I'm partial to the Melling HV pump as it gives good pressure at idle and below.

 

Re-engaging, putting together my rebuilt 225, using the original cover, not much wear showing, torque to spec and the gears turn nice and easy. Install the Melling thrust plate and torque to spec can't get the gears to rotate, as if there is not enough space. Makes me want to just go back to the original set up without the thrust spacer. Suggestions or advice welcomed.

Thanks
Tom

 

Do it the way jeepdaddy2000 said then ?

 

Add a thicker gasket between the pump housing/timing cover and plate the gears are pushing against. Mind you, these gaskets are paper thin..
Your gears are binding because there is not enough clearance on the end of the gears. Too much clearance, you won’t build sufficient oil pressure, especially at idle.
-Donny

 

Thanks Donny