Author Topic: Wet sumping  (Read 529 times)

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Offline 72 yellow

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Wet sumping
« on: January 02, 2020, 10:38:19 AM »
Has anyone used a Vital Motor oil pump leak stopper kit ?  It's on eBay and replaces 15166-300-000 and 15171-300-010 which are discontinued.  Cost is $27.00.  Mine started sumping after 13 years of ownership.

Offline BenelliSEI

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Re: Wet sumping
« Reply #1 on: January 02, 2020, 11:03:27 AM »
I’ve used a kit from Vintagecb750.com that includes the “0” rings that go between the pump and case (and more). It’s a few dollars more, and worked for me. Fairly easy job, if you have the bike up on a table. Good Luck.

Offline PeWe

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Re: Wet sumping
« Reply #2 on: January 02, 2020, 11:09:25 AM »
If you search you will find threads on this forum that has used this kit. There are threads about how to remove the irritating hard sitting oil seal for the shaft. I'll use a tap next time that fit exact and can drag it out.  A tip I saw.

I have used 2 kits. Oil strainer also recommended. Honda original available.

Forum member MessnerMoto has made new rotors, a little bit tighter to ensure oil pressure when engine is very hot. Both my oil pump restores got those too.
I did the pumps with bike on side stand, a wooden plank under to make it stabdin alnost straight.
Removed exhaust  3-4, pan off.
Laying on my back tp see the 3 bolts to remove pump.
Trickier back on, very easy to damage the small pipes that look like knock pins if pump is not exactly parallel with case when takibg it off and on. I learned to have extra home.

Make sure to prime pump with oil and let all air out before assembly.

Update: I had to drain pump in a deep oil bath, releasing the nut on relief valve letting bubbles out. I opened the other 2 bolts keeping the leak stopper valve to vent out a little air too. Made sure that oil could flow in. Pump could now suck better when my thumb blocked one of the 2 holes for oil lines and rotating the sprocket. Same on the other hole rotating in the other direction.
Conclusion: Only drain pump in oil and rotate the sprocket is not enough to get all air out.

"Start" with starter without plugs so it will spin quick  to get pressure lamp going off asap.
« Last Edit: January 02, 2020, 12:40:57 PM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Wet sumping
« Reply #3 on: January 02, 2020, 11:33:02 AM »
The Vital kit is the go to. You MAY be able to get it here with a discount.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)