Author Topic: Stuck valve in oil filter bolt...  (Read 885 times)

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Offline samm_j2

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Stuck valve in oil filter bolt...
« on: August 05, 2021, 11:35:38 AM »
Since my motor is apart to check on the conditions of the main bearing, (I had low oil pressure, shell bearings look fine), I am looking over and cleaning everything..

I noticed that the valve in the oil filter bolt is stuck. I was able to get it out but it took some work. I will definitely need a new one.

Could this stuck valve have been the cause of my low oil pressure??

Thanks

Offline Don R

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Re: Stuck valve in oil filter bolt...
« Reply #1 on: August 05, 2021, 11:43:31 AM »
 Could be, depending if it was stuck in filter mode or bypass mode and how dirty the filter was. There is also info here on how to check the oil pump.
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Offline samm_j2

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Re: Stuck valve in oil filter bolt...
« Reply #2 on: August 05, 2021, 11:56:16 AM »
Pump is in good order.

I'm not sure how far up the valve in the bolt is suppose to go. It was definitely covering the second row of holes, second down if bolt head is top.

How does this valve work anyways??

Offline Whaleman

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Re: Stuck valve in oil filter bolt...
« Reply #3 on: August 05, 2021, 12:07:35 PM »
If the filter is clogged the pressure, instead of going through the filter pushes open the bolt valve to allow oil to bypass the filter and go to the engine. Dan

Offline samm_j2

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Re: Stuck valve in oil filter bolt...
« Reply #4 on: August 05, 2021, 12:25:38 PM »
So I think it was stuck in the "closed" position... meaning that it was most likely NOT the source of my low oil pressure... and the search continues!

Thanms

Offline Whaleman

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Re: Stuck valve in oil filter bolt...
« Reply #5 on: August 05, 2021, 12:53:18 PM »
If it was stuck closed AND your filter was clogged it could cause low pressure. Dan

Offline samm_j2

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Re: Stuck valve in oil filter bolt...
« Reply #6 on: August 05, 2021, 12:59:44 PM »
Filter was/is brand new  :-\

Online PeWe

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Re: Stuck valve in oil filter bolt...
« Reply #7 on: August 05, 2021, 01:00:19 PM »
It was a post about aftermarket oil bolts (17mm head) that was wrongly assembled.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
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Updates of the CB750 K6 -1976
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Offline samm_j2

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Re: Stuck valve in oil filter bolt...
« Reply #8 on: August 05, 2021, 01:20:57 PM »
Pewe, I think I rear that post. The bolt is 17mm for sure so maybe it is an aftermarket one. It came with the bike. The valve was at the top, then spring, the pin. Which I believe is the correct order?



Offline Whaleman

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Re: Stuck valve in oil filter bolt...
« Reply #9 on: August 05, 2021, 02:50:40 PM »
Just buy a new one and be done with it. Dan

Offline maxheadflow

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Re: Stuck valve in oil filter bolt...
« Reply #10 on: August 05, 2021, 07:38:44 PM »
A stuck relief valve would only have an effect on the oil pressure if the filter was plugged up. 

Offline Bodi

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Re: Stuck valve in oil filter bolt...
« Reply #11 on: August 06, 2021, 04:59:33 AM »
Filters flow from outside to inside. The holes nearest the head are beyond the end of the filter allowing unftered oil pressure at the outer end of the piston while the inner end is at filtered oil pressure. A blocked filter creates an increased pressure drop, if that is enough to overcome the spring the piston slides in and uncovers the holes inside the filter and allows oil to bypass the filter. Some aftermarket bolts were assembled in reverse with the bypass always open. Only the holes near the bolt head should be unobstructed at rest.