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Author Topic: Oil Level Dropped, Then Rose  (Read 1738 times)

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Offline Tree

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Oil Level Dropped, Then Rose
« on: October 22, 2011, 12:53:54 PM »
I was surprised to see my oil level abruptly down a quart, but I added a quart to bring in up to the Max level.  About a week later I've noticed it's about a quart overfilled.  This leads me to think I might have some type of intermittent circulation problem.  Has anyone else experienced anything similar and determined the cause?  (It's a '78 750K).
« Last Edit: October 22, 2011, 12:55:41 PM by Tree »
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Offline 754

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Re: Oil Level Dropped, Then Rose
« Reply #1 on: October 22, 2011, 01:11:50 PM »
When it sits a while, oil can leak past the check valve in the oil pump.. then tank appears low.
 When you start it , it comes back up for a while. It may happen only occasionaly at first..
 Quart high wont hurt, but I wouldnt do it if its not getting to full temps every ride..
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Offline singedebile

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Re: Oil Level Dropped, Then Rose
« Reply #2 on: October 22, 2011, 06:13:33 PM »
which is why, (and correct me if im wrong) its better to check the oil when when your engine i warm.
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Offline Tree

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Re: Oil Level Dropped, Then Rose
« Reply #3 on: October 23, 2011, 06:45:51 AM »
I have  been checking it first thing in the morning before riding.  The level had always been very consistent up until recently.  Guess I'll start checking it after it's warmed up from now on. 

More from curiosity, every heard of the check valve becoming bad enough that it had to be repaired or replaced?
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Offline Bob Wessner

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Re: Oil Level Dropped, Then Rose
« Reply #4 on: October 23, 2011, 07:27:25 AM »
Quote from: Tree on October 23, 2011, 06:45:51 AM
I have  been checking it first thing in the morning before riding.  The level had always been very consistent up until recently.  Guess I'll start checking it after it's warmed up from now on. 

More from curiosity, every heard of the check valve becoming bad enough that it had to be repaired or replaced?

Actually, the best time to check oil level is immediately after a ride. That will give you a true reading of the oil level in the tank. And yes, there is a rubber tip on the check valve, that's what goes bad and starts to leak. As far as I know, that part is no longer available.
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Offline bjatwood

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Re: Oil Level Dropped, Then Rose
« Reply #5 on: October 23, 2011, 07:50:29 AM »
Quote from: Bob Wessner on October 23, 2011, 07:27:25 AM
Actually the best time to check oil level is immediately after a ride.

That is how I check my oil too.... ;)
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Offline Duke McDukiedook

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Re: Oil Level Dropped, Then Rose
« Reply #6 on: October 23, 2011, 08:55:06 AM »
10-15 minutes after a spirited ride is what the manuals say.
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Offline Tree

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Re: Oil Level Dropped, Then Rose
« Reply #7 on: October 23, 2011, 03:13:39 PM »
"Spirited ride"  - is that a Halloween thing? :(
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Offline Honda George

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Re: Oil Level Dropped, Then Rose
« Reply #8 on: October 23, 2011, 04:01:28 PM »
I replaced the rubber check valve twice in my 72 750 when the part was still available.
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Offline 74750k4

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Re: Oil Level Dropped, Then Rose
« Reply #9 on: November 20, 2011, 06:38:03 PM »
Quote from: Honda George on October 23, 2011, 04:01:28 PM
I replaced the rubber check valve twice in my 72 750 when the part was still available.

George,

Can you tell me some symptoms you had that made you change that twice?  I get smoke and drips of oil out the pipes during warm up now on my 74. I had swapped the oil pump with one from a 78 case. No problems until I did that.  I guess I'm going back to the old pump. What is so special about that rubber check valve tip? Maybe a silicone rubber piece would last longer.

Martin
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Offline Hondawggie

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Re: Oil Level Dropped, Then Rose
« Reply #10 on: November 21, 2011, 04:09:33 AM »
Quote from: Tree on October 23, 2011, 03:13:39 PM
"Spirited ride"  - is that a Halloween thing? :(

its engrish



 or this

    “Operating Instructions for Motorcycle…

    “When driving please you keep the relaxing moon and wear comfortable clothes, obey the traffic rule and prohibit making the moon impatient…”
http://www.globalization-group.com/edge/2010/07/motorcycle-translation-bloopers/




« Last Edit: November 21, 2011, 05:14:03 AM by Hondawggie »
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