WTB Oil Pump

[Wayne]

Looking to buy for a decent oil pump for 576. When I rotate the gear in the housing mine has a tight spot, even without the impellers installed. I'm just not comfortable with it.

[Steve Swan]

i have a good complete lower crankcase assembly for i believe a 77 or 78 CB750.  i'd need to look at the vin to see what it actually is.   I don't know if these 77/78 pumps are same as 76-earlier, but if they are, you are welcome to have it.  maybe sohc4 has a parts list so you could cross reference.  i'm sure it's a good unit.  let me know

[Wayne]

Thanks Steve. Was there anything unique about the early pumps in "sancast" bikes. I bought one from Ebay (which turned out to be worse than mine) and it looked slightly different. The seller had it listed as 69 thru . It fit and all but without digging it out and having a look, I remember the housing as having a smoother appearance. I guess for a part that's no longer available common sense would say to install the best pump I can get. If there is a unique sandcast run of pumps i can always change it out later if I were to find a good one.

[Steve Swan]

as far as fit and function, i don't know if a later pump such as the one i have will work.  i would think there is a reasonable chance it would.

as far as appearance goes, i would think a 'sandcast' pump would look different than the later pump.

if you can find part numbers on sohc4 or elsewhere and pn's are the same, it's yours.

[kmb69]

Functionally, they are the same 69-78 K's and F's.

You got me wondering now about appearance. These may have been diecast like some of the covers and other parts from day 1.

I plan to check this issue out at the first opportunity.

Keith

[vnz00]

appearance wise, if there is a difference, here is a K0 pump listed on ebay:
http://www.ebay.com/itm/1969-Honda-CB750-Sandcast-K0-KO-CB-750-CB-750-57-working-oil-pump-/221095002664?pt=Motorcycles_Parts_Accessories&hash=item337a4a0228

regards,
Steven.

[kmb69]

That eBay pump certainly appears to have a sandcast base and body.

[Wayne]

That eBay pump certainly appears to have a sandcast base and body.

It sure does! Now all I have to do is to win the darn thing!  I would feel better knowing I'm putting a pump from a sandcast in 576 and hopefully better than the one I have!

[Wayne]

Got my pumps out for another look. The one on Ebay looks like a later pump I purchased a while back. (it also was advertised as 69 thru ) You can see the difference in the end cap and the body casting looks totally different to my original 576 pump. The pump has a number on the cap also. Looks like: 00710914?? Not sure. So unless I find a pump out of a sancast it's piece of mind over as original as it can be. In my mind. the oil pump being a vital component must be sound and can always be replaced later...when I find that NOS part! 

[kp]

http://www.ebay.com.au/itm/69-78-Honda-CB750-K0-Sandcast-OEM-Oil-Pump-Assembly-15100-300-000-/170892900663?pt=Motorcycles_Parts_Accessories&hash=item27ca02b937

[Wayne]

Thanks for the link KP. Just want to bring a couple of observations to the table. Pic's attached.

My original pump has a very gray appearance vs a brighter aluminum appearance on the first replacement pump I bought and the ones that are now on Ebay. (camera flash???) Type of oil used?? haha that reminds me. Back in the 80's we started selling a Red Synthetic Oil. I can't remember the name but I think the company was out of Great Britain. 576 got that oil from there on and still had it in the tank when I got it! sorry, sidetracked!

Also, there has been little or no attempt to clean up the casting flash and parting lines on the 576 pump. All others I have seen so far have witness marks from a grinder, sander, files, whatever they used. Also, the end cap does not have a protruded centre nor does it have a number stamped in it. These are just observations for the group.

Bottom line is I won't be comfortable starting 576 up with her original heart unless I can figure out what is wrong with it. I did put a new seal in the body. Wonder if i nicked the bore or if there's a piece of crap I missed behind the seal.  I'll bet VW has a nice pump sitting on a shelf somewhere I would like to get my hands on!

First 2 pic's original 576 pump. Second 2, pump KP posted.

[kp]

Wayne, yep you are indeed correct in that early pumps were cast differently to the later pumps. My link was to enable you to try and get it as close as you can. My money would be to see if you can fix what you already have. Maybe get Steve Swan to give you one of his as his bikes will never be started so he won't need them 

[Wayne]

Wayne, yep you are indeed correct in that early pumps were cast differently to the later pumps. My link was to enable you to try and get it as close as you can. My money would be to see if you can fix what you already have. Maybe get Steve Swan to give you one of his as his bikes will never be started so he won't need them 

Appreciated KP. I think I'm getting sandcast "madness" so I'm going to order up another body seal, pull it down again and see what the heck is going on.

[Wayne]

Maybe get Steve Swan to give you one of his as his bikes will never be started so he won't need them  

Gotta love that sense of humor! 

[Steve Swan]

What KPster McG does not know is I don't put oil pumps in my engines.   So, i can't sell what i don't have.   for that matter, i did not bother with any of the other internals either.  saves big bucks on a resto if one skips internals !!!!