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Powervalve, disassemble to clean or not?

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Ok i did some searching on this but was surprised to not find any real solid info on what some of you guys with experience are doing.

I've got my engine apart for a top end (using a Wiseco with Tusk gaskets..) and want to make sure my PV is nice and clean while I'm at it. I have no reason to believe it needs anything more than a cleaning as the bike is running fine. So with that said I'm curious to hear what procedure some of you guys are using for the powervalve. Should I plan on disassembling any portions of the assembly or should I just do what I can with brake cleaner etc. and call it good? Or what if I soaked my whole jug in diesel overnight or something like that?

I also noticed that manual wants molibdinum disulfide oil on the valve itself which seems unnecessary to me (especially since I don't have any :thumbsup: ) since it will be covered in oil as soon as I start the motor right?

So anyway please post up your methodology for cleaning your valve and maybe we can establish a good "standard" PV maintenance procedure.

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I'd clean it if it were me.

It's simply one thing less to worry about later when you get the bike back together.

When I did mine, I simply let it soak in degreaser and used the soft bristled brass brush to clean it.

I replaced the seals and associated O-Rings and spring just to be on the safe side because mine is an older bike.

It operates with my pinky and its action is silky smooth...

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+1 Id reccommend it while you already have your cylinder apart, what will it hurt?

I always soak in degreaser as stated above then use a stiff tooth brush to scrub it clean then spray all components down with WD-40 before re-assembling.

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As per my post in the other similar post.

Pull the whole thing to bits and clean it properly. Don't cut corners (I tried without success). Clean the pv components AND the jug ports (the areas where the side valves and main flapper valve operate).

The only way I could clean the assembly properly, was to use oven cleaner... the really strong stuff. Degreaser was OK for a superficial clean, but didn't remove all that baked on spooge at all well.

Another thing, there are a few philips head screws in the assembly (god knows why) which are worth replacing with allen head screws. This will make the next disassembly a lot easier.

I didn't use molidinum grease anywhere. I just lubed all of the components with 2T oil. Haven't had any issues since.

Berg

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Anytime I rebuild a two stroke in the shop I always pull the powervalve assembly as a whole and clean each individual piece.

The Oven Cleaner suggested earlier works great.

Upon reassembly I just put a very, very light coating of high temp assembly lube on the shaft and any other parts that move.

Don't just spray it out with brake or carb cleaner. I've had to clean up that customer created mess before. If you just spray out the area beneath the powervalve covers and replace the cover then fire the bike up.... It will suck whatever is left in there into the cylinder and that will cause a loss of lubrication and subsequent seizure.

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In the manual it looks like a PITA to do on my 05 yz250 so I was hoping I could do a good job cleaning without taking it apart but it sounds like you guys are saying I can't. Thanks I guess I gotta get dirty.

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In the manual it looks like a PITA to do on my 05 yz250 so I was hoping I could do a good job cleaning without taking it apart but it sounds like you guys are saying I can't. Thanks I guess I gotta get dirty.

Yeah the manual makes it all look a bit daunting, but seriously its nowhere near as bad as it looks.

Just take your time, use a bit of common sense and maybe grab a few detailed photos as you go, this will assist you with reassembly.

I rekon disassembling the mechanism was harder than putting it back together again. All in all, its not that difficult.

Berg

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Yeah the manual makes it all look a bit daunting, but seriously its nowhere near as bad as it looks.

Just take your time, use a bit of common sense and maybe grab a few detailed photos as you go, this will assist you with reassembly.

I rekon disassembling the mechanism was harder than putting it back together again. All in all, its not that difficult.

Berg

Couldnt agree more...

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Yeah the manual makes it all look a bit daunting, but seriously its nowhere near as bad as it looks.

Just take your time, use a bit of common sense and maybe grab a few detailed photos as you go, this will assist you with reassembly.

I rekon disassembling the mechanism was harder than putting it back together again. All in all, its not that difficult.

Berg

+1 on the camera.

Considering my last maintenance on a dirtbike was 25+ years ago, if I hadn't had a digital camera to take snapshots of the process, there's no way I'd have been able to do the restoration work to my YZ.

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