Flatten oil pump base

[disquek]

I got a new oil pump from AN and found the base to be not flat.

AN has offered to replace it. But before I ship it back, I'm wondering how hard it would be to flatten it.

I have a small surface plate and some PSA sandpaper. I've flattened plenty of small parts before.

My question is about how to keep the abrasive and debris out of the pump. I know I can disassemble it. But given that the bolts are staked, that seems mildly risky. Given that this is a new pump and should just need flattening, I'm hoping to avoid taking it apart.

Could I pack the ports with grease and then flatten it? Would the grease stay in the ports? Has anyone tried this? (I'd carefully remove the grease after flattening it with something like a dental pic).

-Kyle

 

[850commando]

how much is it out off flat?

 

[disquek]

I didn't get a feeler in to measure it. I just saw light coming through on the straight edge. It's not a ton. But It seems like it should be dead flat.

Also, are folks using a gasket sealant on these oil pump gaskets? 518?

-Kyle

 

[kommando]

Should be no need for sealant, I would be sending it back, sounds like its been bent if you can see light.

 

[oldmikew]

I got a new oil pump from AN and found the base to be not flat.

AN has offered to replace it. But before I ship it back, I'm wondering how hard it would be to flatten it.

I have a small surface plate and some PSA sandpaper. I've flattened plenty of small parts before.

My question is about how to keep the abrasive and debris out of the pump. I know I can disassemble it. But given that the bolts are staked, that seems mildly risky. Given that this is a new pump and should just need flattening, I'm hoping to avoid taking it apart.

Could I pack the ports with grease and then flatten it? Would the grease stay in the ports? Has anyone tried this? (I'd carefully remove the grease after flattening it with something like a dental pic).

-Kyle

What a drag... I would return it in case there are other issues..However on an old pumpm I have always used fine valve grinding paste on plate glass mirror.. no optical distortion means truth... you could plug holes with plasticine but just make sure to wash thoroughly with petrol after wards

 

[MexicoMike]

Agree re sending it back.

FWIW, I've disassembled/resurfaced the oil pumps with no problems with the staked fittings. I use an impact screw driver - the kind that you strike with a small mallet. Put the pump in a vise and the impact driver will remove it easily if a regular screw driver is having any trouble.

 

[RoadScholar]

+1 on sending it back. A/N needs to know about this, and, hopefully will take corrective action including an inspection of their current inventory; it benefits all parties.

Best.

 

[Bernhard]

I didn't get a feeler in to measure it. I just saw light coming through on the straight edge. It's not a ton. But It seems like it should be dead flat.
Also, are folks using a gasket sealant on these oil pump gaskets? 518? -Kyle

Yet another Mon morning / Friday a/ noon assembled pump - I thought they had stopped churning these out by now. Or have they got themselves yet another trainee on the job?

 

[jbruney]

You shouldn't be troubled with a warped surface on a new pump is my opinion... Have you got it in the post yet? If you accept poor quality then all you shall receive is poor quality, besides they'll make it right.

 

[Time Warp]

A straight edge is a bit low tech for checking that surface and being fly cut (most likely) the cutter head would need to be tilted to put a convex surface on that face. (unlikely)
If you are going to check the pump face, do it with machine tools and a dial gauge that reads to 0.0001" or a dial stand on a surface plate unless you want to break it down enough for a blued face check. (Which would most likely void any warranty return on a new part)

 

[marshg246]

I got a new oil pump from AN and found the base to be not flat.

AN has offered to replace it. But before I ship it back, I'm wondering how hard it would be to flatten it.

I have a small surface plate and some PSA sandpaper. I've flattened plenty of small parts before.

My question is about how to keep the abrasive and debris out of the pump. I know I can disassemble it. But given that the bolts are staked, that seems mildly risky. Given that this is a new pump and should just need flattening, I'm hoping to avoid taking it apart.

Could I pack the ports with grease and then flatten it? Would the grease stay in the ports? Has anyone tried this? (I'd carefully remove the grease after flattening it with something like a dental pic).

-Kyle

How do you know it's not flat if you haven't removed the screws? The bottom is not what needs to be flat - it's the mating surfaces.

 

[DogT]

That's what I was wondering, it's the inside against the gears that needs to be flat unless I'm missing something.

 

[L.A.B.]

How do you know it's not flat if you haven't removed the screws? The bottom is not what needs to be flat - it's the mating surfaces.

I think he means the pump to crankcase joint face.

 

[nortriubuell]

I think he means the pump to crankcase joint face.

+1 with L.A.B. ... By "disquek's" posters question/write up; I read the it as the pump face TO THE engine. (NOT the plate that has staked screws that is against the gears.)

 

[Time Warp]

I got a new oil pump from AN and found the base to be not flat.
#
My question is about how to keep the abrasive and debris out of the pump. I know I can disassemble it. But given that the bolts are staked, that seems mildly risky.

The bolts were only mentioned as far as internal debris if it were to be lapped.
Once the pump had any evidence of being tampered with (disassembly) you could kiss any warranty goodbye.

 

[Time Warp]

I think for a budget check, a glass plate with feeler gauges might be more conclusive.
Of course that would be taking for granted the engine case pad for the pump is flat also.

US$399.

 

[Time Warp]

When will someone make a dual stage gerotor oil pump ?

 

[marshg246]

I think he means the pump to crankcase joint face.

Oh, probably so. Didn't even consider that - doubtful that the crankcase is perfectly flat and it gets a gasket.

 

[jbruney]

Gerotors are really nice. My old CR had such and it survived a total engine dusting. I was amazed.

 

[RoadScholar]

When will someone make a dual stage gerotor oil pump ?

BMWs have these pumps, at least the /5, /6 and the /7s, the models I have worked on.

Best.