Author Topic: Pressure in the oil tank?  (Read 1768 times)

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kaysystems

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Pressure in the oil tank?
« on: June 07, 2005, 05:17:36 PM »
I've had an oil leak since I bought my CB750 K0. I'm sure it comes from the output shaft seal. Changing the seal did nothing.

Yesterday I checked the oil level. Today there is no leak. I forgot to tighten the oil cap.

So I assume that I have too much pressure in the tank. The breather must be blocked.

Anyone know how to clean it?

The valve cover breather pipe is connected to the tank & the tank breather is connected to the rear of the transmission. I think that is correct.

Thanks

David    ???

Offline Jonesy

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Re: Pressure in the oil tank?
« Reply #1 on: June 07, 2005, 06:40:13 PM »
The breather tube from the valve cover is supposed to be vented to the open air, as is the large tube from the oil tank. The little hose sounds like it is correctly connected between the tank and the transmission housing.

This might be your problem...
"Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles; it makes me take another look." -Steve McQueen

kaysystems

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Re: Pressure in the oil tank?
« Reply #2 on: June 07, 2005, 06:59:21 PM »
Thanks

Where does the one from the valve cover go? Obviously the one I have is long. If I disconnect it from the tank, do I just let it dangle?

I'm convinced this is my problem.

Thanks again

David  ;D ;D

Offline Jonesy

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Re: Pressure in the oil tank?
« Reply #3 on: June 07, 2005, 07:02:35 PM »
The hose from the valve cover on the early bikes just ran along the upper frame tube under the gas tank and down in front of the battery holder to just below the front of the swingarm, along with all the other vent tubes (from the carb bowls and such). The hose from the oil tank just pointed down towards the ground.
"Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles; it makes me take another look." -Steve McQueen

kaysystems

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Re: Pressure in the oil tank?
« Reply #4 on: June 08, 2005, 04:27:09 AM »
Thanks.

I think I mayneed to get a couple of new hoses. The valve cover one is moulded to shape & runs under the carbs. I need the one on the oil  tank.
No more oil leaks now ;D ;D

Thanks again

David