# Brute burning oil?



## lilbigtonka (Dec 30, 2008)

My buddies brute is burning oil bad and just started....he sunk it a lil over a year ago and filled motor and everything up with clean water.....we flushed it and did everything right, he has no knock and it runs like a top still to this day but I knew it hurt it back then, as it water does all the time....but we usually stay in water so it stays cool yesterday we rode like 8 hrs of straight sand trails with 3 brutes mine and the other were perfect and the other one has been sunk to.....but his burnt a lot of oil so we added some right then filled to h on dipstick got back to camp 30 min later and on L again but still runs awesome and doesn't smoke.....no leaks either, so next step is compression test but if there is blow by I was wondering what's it costing you guys for a hc top end job or even a stock top end job for you guys that don't pull the motor yourself as he wants whoever messing with it to do whole thing and as I haven't broke into a brute like that yet I don't wanna start on my buddies bike....and should we get by without needing a bottom end since it still runs great and no knock


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## lilbigtonka (Dec 30, 2008)

Another thing I'm thinking is bad valve seal....so I am gonna do compression test but after that how would I check for a bad valve seal....


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## dman66 (Feb 20, 2011)

I don't have the answer to your question,but I have noticed that my 05 750 does not tend to eat oil during the colder months.As soon as I get to the spring and summer months,she eats oil - regular dino oil - rotella 15w - 40.I've been wanting to install an oil cooler,and have most of the parts but the hoses - I think an oil cooler will help from eating oil.Also I plan on doing a compression test cold,then after she's been warmed up to see any differences.with a 1000+ miles,I'm sure new oil seals would'nt hurt.


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## brute for mud (Jul 15, 2010)

To see if it's valves or rings do a compression check on both cylinders then put a little oil in the cylinders the compression should go up a little not a lot if it jumps a lot its rings and not valve guides and seals


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## Waddaman (Oct 3, 2010)

It's probably a combination of both it puking into the air box and valve seals. Mine used to do it and now does again the same **** thing. No smoke, no nothing just burns oil slow but steady.

I had the exact same thing happening to me before I did the 840, thought my cylinders were shot and she needed a top end. Took off rocker cover and 2 oil seals were off the guides just banging around on the valve stems. Wasn't a scratch in the cylinders. Before you order anything, take off the intake and exhaust and look in the port's. If you see a glossy liquid or anything else but dry carbon on the valves it's probably a valve seal.

I think the problem lies with the guides.. Stock valve seals suck, metal outside rubber inside and they just jam/sit on the guide. But now on my 840 even with kibblewhite valve seals with a spring seal on the stem and a ring lock over the guide part of the seal I have one that fell off now. A pretty easy way to tell is if it smokes on start up after say a week without running, oil sits on the head slowly leaks through the valve guide onto the valve or in the combustion chamber. once you start that pooled oil burns off and from there on out while running it only burns constant/smoothly not random bursts, also usually doesn't show smoke because it lets it out slowly but constantly.

Do the compression test, if it's good definitely take a look at the seals before ordering anything.


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## lilbigtonka (Dec 30, 2008)

Well I just checked the air box when I open the butterfly with the throttle open, the valves on front and rear looked super clean and shiney.....so that is making me think worst the rings


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## countryboy61283 (Mar 20, 2010)

Mine was doin the same thing exactly after a year after I sunk, burning oil fast with no smoke and plenty of power. It was the rings on mine and the valves. I sent mine to amr and he said it wouldn't be wise to put a fresh hc top end on a bottom end that's been sunk


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## Winnipeg-Roy (Mar 3, 2012)

Top end jobs are not that difficult do a compression test with a little oil in the cylinders, do a search and find out the proper way to do a leak down test and that will tell you exactly what's wrong. Could be something simple.


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## J2! (May 8, 2010)

Put each cylinder to top dead center then pump each one up. The valves should be closed. If you are getting air coming through the carb you have an intake valve seal problem. Air coming from the tailpipe is an exhaust valve problem. Then pull the dipstick out, if air is coming out of the crankcase it's a ring problem.


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## Waddaman (Oct 3, 2010)

J2! has a really good point there. What I should mention is both my valve seals the first time were exhaust valves.

Like said above, do a compression test and get the info. It's easy to do just get it over with sitting there wondering just makes thing's worse, Lol.

If it is rings, Countryboy has a point. Before i'd order anything id take the whole top end and bottom end apart, check your rod and main bearings for sure see what kind of damage is done down there. if your crank is good throw some bearings in it order a HC kit and go again. If your cranks bad then.. well you can make the choice weather to put that much money into it or not.


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## wfocf (Mar 8, 2012)

mine done something close to that but i had lil smoke for few mins when you let it set an cool down or first crank it up after a few days now i gotta rebuild it prices i got *800-1500 top end an 2000-2700 for whole thing


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