# Unadjusted Valves = Oil Consumption?



## DanOMite (Oct 20, 2011)

Alright, so I finally got around to having a leak down test performed on the Brute because I noticed it was starting to eat oil. 

Test results: Front cylinder compression 45psi and rear 65psi. The dealer recommended I get a valve job to see if the leakage was due to unadjusted valves. It turns out the front exhaust valves were too tight, rear valves were good.

Leak down test #2: The front compression increased to 60psi. So, the front cylinder has about 10% leakage all said and done. 

I’m riding this weekend to see if the adjustment helps with the disappearing oil. 

Would unadjusted valves cause oil to be consumed?

Any feedback would be great.

2008 Brute 750i
1087 kms / 675 miles
100 hrs use


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## Waddaman (Oct 3, 2010)

valve adjustment shouldn't have anything to do with oil consumption.

Simple question. Do you jab the throttle alot? (from a stop to wide open and holding it) and do you do a lot of wheelies? this will cause oil to puke into air box and burn.

if it's internal and it's probably just something stupid like a bad valve seal or something like that. (as long as u didn't sink the quad)


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## kygreen (Oct 15, 2011)

wow your machine is still really new, i dont think the valves would have very much oil consumption difference but the valve seals would?


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## No_Substitue_For_A_Brute (May 4, 2011)

It has been my experience that as the valves tighten up there seems to be more crankcase blow by causing much more oil to be pushed into the air box.

Sent from my ADR6400L using Tapatalk 2


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## DanOMite (Oct 20, 2011)

Waddaman said:


> valve adjustment shouldn't have anything to do with oil consumption.
> 
> Simple question. Do you jab the throttle alot? (from a stop to wide open and holding it) and do you do a lot of wheelies? this will cause oil to puke into air box and burn.
> 
> if it's internal and it's probably just something stupid like a bad valve seal or something like that. (as long as u didn't sink the quad)


I do hit the throttle a lot and do wheelies from time to time. I've never sunk it , I don't go too deep b/c I don't have snorkels. 

I've never seen blue smoke come from the exhaust but when you're booking down a dirt road it would be tough to see. At idle and when I rev there is no smoking.


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## DanOMite (Oct 20, 2011)

No_Substitue_For_A_Brute said:


> It has been my experience that as the valves tighten up there seems to be more crankcase blow by causing much more oil to be pushed into the air box.
> 
> Sent from my ADR6400L using Tapatalk 2


I didn't check the air box for signs of oil but it would explain where it's going. 

Thanks all for the feedback!


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## adam6604 (Feb 5, 2012)

nailing the throttle lots cause oil to puke into the airbox?!! sheesh..wish i knew that, lol might of saved my brute.. haha


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## countryboy61283 (Mar 20, 2010)

The crankcase vent is comes out underneath the air filter, lots of wheelies and wot a lot will give it a straight shot of oil to the cylinders


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## adam6604 (Feb 5, 2012)

well i do ALOT of WOT while riding muskeg. so that's probably what did it in. lol


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## countryboy61283 (Mar 20, 2010)

Lol it happens, get u a catch can


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## DanOMite (Oct 20, 2011)

Sounds like I should do the catch can mod... 

Would 10% leakage on the front cylinder cause it to burn? Logically I would think yes because if it can get by the rings it will burn it up. I sometimes travel down gravel / dusty roads at about 75kms/hr (46 mph) for about 10 minutes. I don't always blast at WOT but when I do I hold it for about 30 seconds or so. Wow the air filter sure gets dirty fast when riding in dusty conditions. 

I regularly hit the throttle from a standstill because I love how the Brute launches :rockn:. If it gives it a shot of oil to the cylinders every time I do this I need to relax my heavy thumb.


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## Waddaman (Oct 3, 2010)

You can keep doing it if you get a catch can.

If you've never sunk it and kept the oil/filter changed there is no reason for there to be anything wrong internally with the engine. 100 hours is nothing. This is UNLESS you let your air filter get real dirty and then get into cylinders. 

If it's getting considerably brown, wash it. It will just continue going through into your engine if you don't. you can take it off and check the metal screen inside, wipe your finger across it and if there's ANY dirt on it you got a problem. I did this by accident this summer but very very little, i have 2x 2" snorkels with 1 coming in from the side only about 3/8 gap between it and air filter. of course that one spot was really dirty and rest of air filter was pretty good. I thought i should check it anyway so i did and sure enough there was little dust on the inside. It got that dirty in 2 rides this spring. ive washed my filter 4-5 times this spring alone (barely drove it engine is apart in garage now...) and it needs to be cleaned again.

Anyway.. the moral of the story is even if 1 section is dirty looking and the rest is good clean it anyway, not worth risking it.


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## DanOMite (Oct 20, 2011)

I just checked the metal screen inside the filter and you nailed it. I took the screen out, wiped it with a paper towel and there was some dirt. It was a very little amount, barely there. I also noticed some oil under there too. 

Well, I guess that would explain why my oil was getting so dirty so quickly and disappearing. 

If the filter was very dirty and restricting the amount of airflow, could it potentially suck some oil out the crank case vent?


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## Tempsho (May 28, 2010)

DanOMite said:


> Wow the air filter sure gets dirty fast when riding in dusty conditions.


You would be surprised at how much longer your filter stay clean for if you install snorkels!


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## Waddaman (Oct 3, 2010)

???? Cleaner with snorkels? I don't know about everyone else but with snorkels mine gets dirty Wayyyyyyyy faster. Underneath it's not out in the open is blocked behind the plastic cover, plastics, rad etc. Snorkels it's straight up in the air straight shot to the air box. Although without snorkels mud will splash up there if that's what you mean.

You should be good Dan, if your compression is at 60 i doubt you caused any problems manual says 36-66 so your up there. I wouldn't worry about that. get yourself a Catch can and clean your filter real good/oil it and it shouldn't burn any oil.


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## DanOMite (Oct 20, 2011)

Thanks again Waddaman!


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## Tempsho (May 28, 2010)

I drive down a lot of dusty trails, so what I found was that intake was sucking in all the dusty air that got kicked up and circulated underneath all the plastics. With the snorkels installed, the intake is able to suck in (relatively) cleaner air. I guess it all depends on what type of riding you do, but for me they stay cleaner.


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