BN2 Oil Pump Disassembly

[Dave Russell]

On my BN2 oil pump, gear type, how do I get the driven gear off it's shaft. The gear does not want to come off the shaft. I can't drive the shaft out of the gear with the key in place since the key will not go through the shaft housing bore & can't get the gear off the shaft to remove the key. There is no place to get a grip on the gear with a puller.

What do you suggest?
D

 

[Keoke]

Hi Dave, do you have access to a hydraulic press? If so you can press the gear off the shaft.-FWIW--- Keoke

 

[Dave Russell]

[ QUOTE ]

If so you can press the gear off the shaft.-FWIW--- Keoke

[/ QUOTE ]
That's just the problem. The gear is in the housing. There is a halfmoon key in the shaft. The key will not go through the shaft bearing, pump housing, of course. The shaft can only be pressed part way out of the gear before the key reaches the shaft bore & can't go any further. This is not far enough to release the gear from the shaft.
D

 

[Keoke]

OK Dave, Thats a bad scene. Maybe you can make up some small shims that take up the space between the back of the gear and the housing and force the shaft to move that distance. building on this concept to increase the distance the gear moves up the shaft until it comes off.? FWIW---Keoke

 

[Dave Russell]

Thanks Keoke,
That's about the only thing that I can think of also. It's going to be slow going, but not the first time that something has been difficult on these cars.
D

 

[Keoke]

Yeah Dave, It just going to Micro Inch along.---Keoke

 

[AndrewMawson]

Dave,

The pump is available at a fair price here in the UK - I'd be very tempted to put a new one in.

When I took mine out of my BJ8 to examine it when I had low pressure, it measured fine, just very slight scoring on the housing from sludge being pumped round at the gear tips. If I had relied on the factory manual measurements it would have passed muster. I put a new one in and hey-presto had good oil pressure. /ubbthreads/images/graemlins/savewave.gif

OK the BN2 one is slightly more costly than the BJ8 but we are talking 'heart of the engine' here !!

/ubbthreads/images/graemlins/england.gif

 

[Michael Oritt]

Dave--

If you haven't already done so now would be a great time to upgrade the original copper hose between the pump and block to a modern hose w/braided jacket. The nipple at the pump end on mine broke off and I was lucky enough to see the oil pressure plummet. I believe both Denis Welch and AH Spares make nice units with swivel fittings for easy installation.

 

[Dave Russell]

Andrew,
Thanks for the suggestion. I have a high quality new pump from Denis Welch. The BN2 pump drive shaft with it's built in gears is over $300 extra. I don't need the shaft, so am transferring the shaft from old pump to new pump, that is, if I can ever get the old shaft out.

Michael,
I certainly agree with you. I have a new Denis Welch oil pump, braided flex line, & aluminum sump. Just having trouble getting the shaft out of the old pump so that I can put it in the new one.

Does anyone have a spec for end clearance (float) for the shaft/gear combination? I hesitate to just duplicate the old clearance.

I have been well aware of your "close call" & it is the main reason that I am pulling the pan. Have been paranoid about the line breaking every since you first mentioned the subject. I am debating whether to install the two horizontal DW provided sheetmetal sump baffles or leave them out. They aren't close enough to the crankshaft to act as a windage tray & I wonder about their effectiveness on a street driven car.

Thanks guys, I appreciate your help. Any further comments appreciated.
D

 

[Keoke]

/ubbthreads/images/graemlins/savewave.gifFurther Comment /ubbthreads/images/graemlins/smile.gif
Well Maybe!- Gear End Float = 0.0016"-to-0.005" Gears to Pump Body = 0.0005"-to- 0.002" ---Keoke /ubbthreads/images/graemlins/angel.gif PS these pumps are kinda like Crank Journals if you can feel swirls on the parts with your finger nail its probably Kapoot.