2009 M8 oil Pump sticking

donaldej

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Dec 10, 2007
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Corvallis Oregon
07 m8
Checked mine as i was doing an upgrade and sure enough it was sticking. I just did as others have done and tightened the spring and it works great now. I have to tell you that tightening the spring is NOT as easy as you think. If i didn't have the skid plate off it would have been impossible.
 

sledbilly

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Apr 9, 2007
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much easier to remove the hood, air silencer and rubber boot, and then access the oil pump return spring thru the bulkhead with a pair of needle nose. On the attached you can see how I increased the tail of the spring around the post.
 

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Jeff K

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Jan 26, 2008
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I did the o-ring fix last night after my lubing job failed to yield long term results. I took off the airbox, bumper and the throttle body intake to get at the pump arm easily. I used 2 small o-rings on the shafts and a third oring over the top to keep them from falling off.
 

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Aug 22, 2009
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Minnesota
Are you sure?????

I am pretty sure most of your oil pumps are just fine??? Do you know you should be checking it while the sled is running??? Pretty sure you will find different results when checking your oil pump while it's running and not running??? It must run off of some type of eccentric shaft or something?? Cuz mine does'nt return ALL of the time when not running and returns like it should when it's running. Are you guys checking these while they are running or not? Post your results if you are finding the same me. I would like to know if this is right or not.
 

aktreekiller

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Dec 16, 2008
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hey

I'm sure you all know this, but the oil pump is designed to not slam shut when the throttle is let off. Its the only pump the works in reverse also.
 
Dec 1, 2007
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wyoming
I'm sure you all know this, but the oil pump is designed to not slam shut when the throttle is let off. Its the only pump the works in reverse also.
CHecked mine running several times last year starting fouling plugs got tired of no answer from the cat (they wouldn't even replace the pump gave me the its supposed to do that line) used safety wire and tied the two tabs together. works great now took a entire ride before it finally cleared its throat what a piece of junk if you ask me mikikuni (dont know how to spell) oil pump. Took it apart while i was there has a small detent ball to park the throttle shaft i could barely close it in my hand junk!!! Slowly backing of the oil is a nice idea in concept but in reality not so good.
 
I am pretty sure most of your oil pumps are just fine??? Do you know you should be checking it while the sled is running??? Pretty sure you will find different results when checking your oil pump while it's running and not running??? It must run off of some type of eccentric shaft or something?? Cuz mine does'nt return ALL of the time when not running and returns like it should when it's running. Are you guys checking these while they are running or not? Post your results if you are finding the same me. I would like to know if this is right or not.
I'll admit I checked mine while not running. Depending how fast or slow I let off the throttle, it returned to a different spot every time. Now you have me curious :confused:
 
Nov 3, 2009
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BUMP

Just bought a 2010 M8 LE and mine is also doing this. I also noticed a good amount of oil spray under the hood and all over the motor and pipe. It was said that this spray was caused by some blow by oil where the Y pipe and pipe connect at the gasket. If this is the case should I take it apart and re RTV the gasket connection? I have a feeling it might be from the oil pump sticking open from what I have read.

Also I am hearing a "clacking" sound coming from close to the motor. Any ideas on what this could be or if its something little that I am missing that is vibrating against metal to metal??
 

aksnopro

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Mar 11, 2008
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yeah

yeah and just so you know i used to work on polaris's and this mukini or however you spell it oil pump is pretty standard on a lot of sleds so its not just the cats that are doing it. its most all the mukini pumps!!!


and yes high temp silicone on the donut right outa the y pipe and you will never have a leak again.

also your sled will lean itself out at about 500 miles once broke in.

i definatly know the 2010 even running rich is getting better fuel econimy then my 08 m8
 
also your sled will lean itself out at about 500 miles once broke in.
Can you elaborate here? Why 500 miles? why will it lean itself out?

My 09 M9 HCR had a low end bog right out of the box, and after 200+ miles now is has gotten a little worse. I have to give me a few shots of gas to clear it up. I also got the oil pump tied to the throttle lever thing to make sure the oil pump retracts all the time. I got to check my belt deflection has it seems to have a bit of play.
 

Wrenchmaster

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Jan 24, 2011
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with a pair of needle nose pliers you can get under the return spring tail that is on the post in the above pics that has the index mark on it. then pick up spring and wrap tighter around post. I did a couple times and works fine now and still have full rotation of cam arm.

on the xfire only had to remove hood, air box, and sleeve between air box and throttle bodies. easy to reach the return spring with needle nose pliers thru the bulkhead where the sleeve goes.



I know I'm resurrecting a super old thread here. My TM8 started doing this on the weekend. Throttle is sticking and found the oil pump is the cause. Is tightening the spring and adding the O-rings the fix? Since it seems that's what worked when this thread ran out, looks like that's what I'll try. Super annoying riding my sled home at 30KPM, I couldn't open it up or it'd stick.
 
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MI1M600EFI

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Nov 15, 2008
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It doesn't seem like the oil pump could cause your throttle to stick... The problem discussed in this thread is that the throttle opens the oil pump lever, but isn't connected, so the oil pump can remain in high flow and only it's spring returns it to low flow.

Because of that, it seems that the oil pump can stick wide open, with the throttle still working normally. People either tightened the return spring on the oil pump, or used an o-ring to link the oil pump lever directly to the throttle, which made the throttle return force the oil lever back to low flow when you let off the throttle.

You have the opposite, where your throttle is sticking... Unless someone already did the o-ring thing on your sled to tie them directly together, and the oil pump is really hanging up, it seems like your oil pump lever can not be the cause of your throttle sticking issue... And tying the oil lever to the throttle lever is certainly not the "fix".


I would recommend a good dose of lube on the throttle body shafts and linkages. Remove the throttle cable and that'll tell you if it's the cable or the linkages...
Good luck!
 
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Wrenchmaster

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I was thinking the same thing after I read a ton of posts about the oil pump hanging up, it can’t really cause the throttle to stick. Got it apart after work this afternoon, turns out an O-ring that seals the air box to the throttle bodies got cut and stuck in the butterfly in one of the throttle bodies. I’m trying to post a picture but can’t with my phone. It’s got a CPC Stage 2 kit on it, the air box is friction fit to the TB’s with big O-rings and it’s hard to get them lined up square in the chassis to get them back on. I’ve had hard starting issues with this sled for a couple years now, I’m wondering if this was part of my problems? I hope so
 
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