Author Topic: 1970 Cb750 Oil tank connection  (Read 2048 times)

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_DK_

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1970 Cb750 Oil tank connection
« on: August 25, 2009, 06:17:48 AM »
I had a hairline crack in the back of the tank, I had it welded up, so problem solved?  Well one problem solved...
I put the tank back on, attached the braided hoses and the larger rubber hose to the back of the trans. Where does the smaller rubber hose go? it didnt appear to be attached to anything before, but now its spewing oil from it.  The tank isn't over full.

Offline 754

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Re: 1970 Cb750 Oil tank connection
« Reply #1 on: August 25, 2009, 09:56:33 AM »
I think small hose goes to trans, big hose vents to atmosphere..just hangs down.
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Offline Johnie

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Re: 1970 Cb750 Oil tank connection
« Reply #2 on: August 25, 2009, 09:58:03 AM »
I think small hose goes to trans, big hose vents to atmosphere..just hangs down.
Beat me to it. Sounds like you attached the wrong one to the tranny. The other is the vent...
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Offline MCRider

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Re: 1970 Cb750 Oil tank connection
« Reply #3 on: August 25, 2009, 10:22:06 AM »
I think small hose goes to trans, big hose vents to atmosphere..just hangs down.

Yup.
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"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

_DK_

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Re: 1970 Cb750 Oil tank connection
« Reply #4 on: August 25, 2009, 11:05:44 AM »
I'll take another look after work, I rode it in, hopefully I didnt break anything. I rode it about 4-5 miles last night before putting it up and it wasnt leaking. The trip to work was about 20 miles, most of it at 50+mph

_DK_

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Re: 1970 Cb750 Oil tank connection
« Reply #5 on: August 25, 2009, 12:13:07 PM »
Looking from the top of the tank, Right now I have the trans connection plugged as pictured.
Should that hose be on the other connection? The one on the right side of the pic, thats not shown?

If I have it wrong would it matter if I'm in gear or not to see if its connected correctly? when I start it nothings leaking/spewing out of the other hose.

Offline MCRider

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Re: 1970 Cb750 Oil tank connection
« Reply #6 on: August 25, 2009, 12:26:10 PM »
I can't focus on what your picture is showing. But simply put, the tranny hose goes to the lower spigot on the oil tank. It is a rather small hose, and the tranny spigot and the oil tank spigot are the same size.

The larger hose coming off the breather/separator at the top of the oil tank simply hangs down in space.

It looks like you may have the small hose plugged into the larger hose? In any event, what I said above is the way it should be.

These are both breathers and do not contain oil of any amount other than what condenses from vapor. From the tranny, you can get some liquid oil if its left open and you run it hard.

Starting and running the engine may or may not produce any drippings depending on other factors.
« Last Edit: August 25, 2009, 12:32:36 PM by MCRider »
Ride Safe:
Ron
1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."

_DK_

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Re: 1970 Cb750 Oil tank connection
« Reply #7 on: August 25, 2009, 03:45:30 PM »
Thank you, I think I got it, I did have the larger hose on the tranny and oil was just spewing around it in high gears.

I'm thinking about building a custom oil tank as i'm tired of burning my leg on the current one, I think I can tuck something under the battery and come up where the current one is, but make it slimmer.  Has someone done something like this before or is there already an aftermarket tank I could start from?