8ba oil pump question

[19Fordy]

I have an 8BA oil pump and am wondering if it would be ok to flip the cover plate over and reinstall it for the two gears so as to provide a fresh, new surface for the gears as shown in the third photo. The current swirl marks you see are extremely light with no damage to the end plate or gears. I don't have any particular reason to "flip" the cover but am just wondering. Thanks, JIM

[petehoovie]

Originally Posted by 19Fordy

I have an 8BA oil pump and am wondering if it would be ok to flip the cover plate over and reinstall it for the two gears so as to provide a fresh, new surface for the gears as shown in the third photo. The current swirl marks you see are extremely light with no damage to the end plate or gears. I don't have any particular reason to "flip" the cover but am just wondering. Thanks, JIM

[69a]

It probably makes no difference, either way. The main concern is that the surface that faces the gears is flat and smooth. The bruising of the surface caused by the spring washers will be worse than the slight wear on the surface. And now you have done it to both sides.
Get a sheet of fine sandpaper on a piece of glass and make one side flat again.

[pistonbroke]

Been there done that, and in later rotary style pumps as well. It needs to be a smooth flat surface for the gears to ride on and to seal around the edge to the case. It's kind of like half of a rebuild. A complete rebuild would machining pump case and gears if necessary to get the correct clearance between the gears and the fresh cover plate surface. Tim

[19Fordy]

I noticed that one of the gears is pinned and doesn't come out and the other mating gear is free floating with no pin and can fall out once cover is removed. This "free floating " gear (on the right in the first photo) rides against the cover. The pinned gear is probably preset by the pin .

Wonder what the gear/cover clearance is suppose to be? I assume both gears ride in a puddle of oil. Thanks for the replies. Jim

[tubman]

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The gear/cover clearance is given in the reprint of the manual I have for '49-'51 Fords. I don't have access to it at the moment, but I believe it is .008"

[Bored&Stroked]

I put mine on a surface grinder and take as little off the bottom as possible. Since most don't have a surface grinder, I'd just take the plate down and polish it a bit on a piece of flat stock with some 600 grit. Truth be told, there is so little wear - probably not an issue in the least.

[Bored&Stroked]

Also, the gasket is extremely thin - sometimes the "gasket kits" from folks like Speedway have a gasket that is way to thick. So check the new gasket before you use it. Sometimes I mic the original and use a piece of thicker paper to make my own gasket.

[19Fordy]

How do you adjust for the thickness of the gasket when using the .008 in. clearance?
A piece of 8 1/2 x 11 paper stock is about .005. Would that be ok to use as a gasket?
Thanks.

[Bored&Stroked]

As long as you have some clearance, you should be fine. Heck, the crankshaft main thrust only needs .005 or so, so I can't see a lubricated oil pump needing more than that! Of course this is just me babbling, but honestly - anything over a couple thousandths should be fine.

[vincent]

Any gear type pump would only need the minimum of axial play. No need to worry if you only got 1 thou - as long as it spins without friction. So all the geartype pumps that I overhaul go on the grinder with installed gears. As soon as the grinding of the housing starts to grind the gears as well, I stop the grinding. Remove the wheels and grind them 1/2 thou to restore minimal clearance in the housing. If there is only minimal radial clearance on the gears you will have a good/high pressure oil pump. If axial clearance is minimal but radial clearance is a lot due to a worn housing or gears, your oil pressure will suffer.

[19Fordy]

Thank you gentlemen for sharing your wisdom.