Author Topic: Oil pumps  (Read 2462 times)

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Offline Dion

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Oil pumps
« on: August 26, 2013, 11:32:49 am »
Hi chaps,  I am currently building a 750 sohc using 836 pistons, new rods, cam, etc. so I am putting quite a few bucks into the build. I can't find a replacement oil pump. I have concerns using a 40 year old pump. What do u chaps do when it comes to oil pumps?...

Offline MRieck

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Re: Oil pumps
« Reply #1 on: August 26, 2013, 11:49:22 am »
Very interesting timing. I just got off the phone with Kenny @ CycleX....there will be oil pumps (more like rebuild kits) in the near future. It will include new rotors, end caps and drive shaft seal. The new pieces will be made to closer tolerances and better materials. The original rotor housing and mounting plate will be the same. I believe the relief valve spring will be a bit heavier.
 I believe Kenny will be offering replacement "leak stopper" rubbers. Not sure when that will happen but there is movement.
Owner of the "Million Dollar CB"

Offline MRieck

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Re: Oil pumps
« Reply #2 on: August 26, 2013, 11:53:28 am »
Hi chaps,  I am currently building a 750 sohc using 836 pistons, new rods, cam, etc. so I am putting quite a few bucks into the build. I can't find a replacement oil pump. I have concerns using a 40 year old pump. What do u chaps do when it comes to oil pumps?...
For now I find a pump with best parts in it. I measure/clean up the rotor tips and sides with 400 paper as well as the inside of the caps. I replace the drive shaft seal ( a PITA) and the cap orings. I replace the oil stopper rubber though they are NLA ( I have some new spares).
Owner of the "Million Dollar CB"

Offline Dion

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Re: Oil pumps
« Reply #3 on: September 08, 2013, 07:12:49 am »
Hi chaps, found a 18 OD diameter oil seal with same ID for the pump and milled the pump to accept this seal. So this issue is resolved. The seal costs R10 ($1). Any ideas what to do about the oil stopper rubber?

Offline 70CB750

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Re: Oil pumps
« Reply #4 on: September 08, 2013, 09:10:39 am »
Member here just announced he is gonna make some.

Offline Dion

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Re: Oil pumps
« Reply #5 on: September 08, 2013, 10:10:33 am »
Sent him a mail last week and he only offered me a second hand part  :(

Offline voxonda

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Re: Oil pumps
« Reply #6 on: September 08, 2013, 10:23:57 am »
Have some new(!) ones in stock.

Better sorry for failing then for the lack of trying.

Offline Dion

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Re: Oil pumps
« Reply #7 on: September 09, 2013, 07:03:26 am »
If we could get a manufacturer to make us a run of the correct size oil seals , do u think anyone would want ?

Offline 70CB750

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Re: Oil pumps
« Reply #8 on: September 09, 2013, 07:11:39 am »
If we could get a manufacturer to make us a run of the correct size oil seals , do u think anyone would want ?

That's exactly what I was trying to tell you:

http://forums.sohc4.net/index.php?topic=126362.0

already in process.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Oil pumps
« Reply #9 on: September 09, 2013, 08:33:25 am »
Hi chaps, found a 18 OD diameter oil seal with same ID for the pump and milled the pump to accept this seal. So this issue is resolved. The seal costs R10 ($1). Any ideas what to do about the oil stopper rubber?

Stock oil pump shaft seals are available from Honda as an early Gold Wing part. It is a xxxxx-300-xx part. The -300 signifies 750 however you will NOT see this part listed on a 750 schematic.

« Last Edit: September 09, 2013, 08:48:26 am by Jerry Rxman Griffin »
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Jim F

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Re: Oil pumps
« Reply #10 on: September 09, 2013, 09:44:39 am »
And I have a great source for O rings and seals up in the New England area.............
these are the ones that I had made for the bottom end automatic kits.........So far there haven't been
any complaints

Let me know if I can help

Jim
2002 RC51 1000 (SP2)
1983 GS1100EC Suzuki
2002 998 Dukati (Customers Bike)
1992 KTM500 2 stroke
1975 CB750/836 Honda
1978 GS750/840 Suzuki

Offline 01Thomas

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Re: Oil pumps
« Reply #11 on: September 09, 2013, 12:00:19 pm »
sooo... can we assume that the whole number is the one shown in the above photo: 91208-300-003  ?

regards
Thomas
1971 Honda CB750 Four K1 [Engine: CB750E-1113521 / Frame: CB750-1113838]
1977 Seeley Honda CB750F (F1) [Engine: CB750E-2551214 / Frame No: SH7-655F]

'96 Yamaha YZF750SP & '81 Moto Guzzi SP1000 & '80 Moto Guzzi 850 LeMans II & '82 Bimota KB-3 [Frame No 49] & '66 Ducati 50 SL/1 & '53 Miele K-50 & '38 Miele 98

Offline KrautKoffin

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Re: Oil pumps
« Reply #12 on: September 09, 2013, 12:11:04 pm »
sooo... can we assume that the whole number is the one shown in the above photo: 91208-300-003  ?

regards
Thomas

 :o
74 cb550
I now have Beastie Boys "Sabotage" stuck in my head after seeing your avatar.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Oil pumps
« Reply #13 on: September 09, 2013, 02:32:11 pm »
sooo... can we assume that the whole number is the one shown in the above photo: 91208-300-003  ?

regards
Thomas

Yes we can. Sorry, thought it was obvious  ???  The other o-rings are for the sides of the pump.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Doctor_D

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Re: Oil pumps
« Reply #14 on: September 09, 2013, 04:27:15 pm »
subscribed
Take care,
David
___________________________________________
1975 CB 750F - Project page: http://forums.sohc4.net/index.php?topic=66026.msg725479#msg725479
1978 CX500
1971 Norton Commando

Offline 01Thomas

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Re: Oil pumps
« Reply #15 on: September 10, 2013, 11:01:44 am »
Thanks JRG. The number for the o-rings is also a help.
1971 Honda CB750 Four K1 [Engine: CB750E-1113521 / Frame: CB750-1113838]
1977 Seeley Honda CB750F (F1) [Engine: CB750E-2551214 / Frame No: SH7-655F]

'96 Yamaha YZF750SP & '81 Moto Guzzi SP1000 & '80 Moto Guzzi 850 LeMans II & '82 Bimota KB-3 [Frame No 49] & '66 Ducati 50 SL/1 & '53 Miele K-50 & '38 Miele 98

Offline spiritof67

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Re: Oil pumps
« Reply #16 on: September 22, 2013, 11:17:41 am »
..and after that, what is the wisdom on replacing the relief valve spring with a stronger one/shimming it how much) to raise oil pressure?