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yz250 top end help

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I just bought a 2001 yz250 2-stroke and was so excited and dumb enough to not check for fluids and i ran it with no coolant in the radiator.  The piston is destroyed by the exhaust port and am sure i either need to get the cylinder ported or get another sleeve, i know i need a piston too.  I atyack a couple of pictures does the head look ok or does that need to be replaced?  The entire engine is stock by the way. (I am only 16 so please give me a break) It will take a while before i can do anything with it to get some money but does it have a sleeve in the cylinder? If so where could i go to get it removed and the other one put back in?  Could i do it myself?

IMG_1188[1].JPG

IMG_1189[1].JPG

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Just clean it man honestly throw and after its clean and shiny look for scratches or gouges if there aren't any and just scoring this burnt marks should be fine throw a piston in and run it for 3-5 minutes shut it off and compression test it

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The scoring are the burnt looking spots and tmit should be fine but I can't really see it all to we'll so inspect and look for any spots omwere it isn't flat

Sorry my typing is aids I'm on my phone

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It definitely got hot but the exhaust side of the piston is just worn from a lot of detonation. I doubt your 5 minute run could wear it that much, somebody may step in and prove me wrong. It needed a replacement so you were kind of forced into the right path.

Do the rebuild right and you will be good to go, don't rush it.

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It definitely got hot but the exhaust side of the piston is just worn from a lot of detonation. I doubt your 5 minute run could wear it that much, somebody may step in and prove me wrong. It needed a replacement so you were kind of forced into the right path.
Do the rebuild right and you will be good to go, don't rush it.

Idk whay the whole cylinder looks like but to me I think a new piston would be fine the head looks fine except all could use some cleaning correct me if I'm wrong?

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It looks pretty trashed to me. But you may be right too. Ill let someone else give their opinion.

That's what I was thinking you also can't really see the cylinder

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On 3/28/2017 at 9:07 PM, dunneryz said:

I just bought a 2001 yz250 2-stroke and was so excited and dumb enough to not check for fluids and i ran it with no coolant in the radiator.  The piston is destroyed by the exhaust port and am sure i either need to get the cylinder ported or get another sleeve, i know i need a piston too.  I atyack a couple of pictures does the head look ok or does that need to be replaced?  The entire engine is stock by the way. (I am only 16 so please give me a break) It will take a while before i can do anything with it to get some money but does it have a sleeve in the cylinder? If so where could i go to get it removed and the other one put back in?  Could i do it myself?

IMG_1188[1].JPG

IMG_1189[1].JPG

Does not look to be sleeved.

Heads fine, needs to be cleaned up is all.

A top end with re-plate and piston will be about 300.

Gasket kit for top end will be about 45.

Recommend a carb rebuild also.

Carb kit 30, new air filter 28. 

Manual on-line is free.

Advice from us guys is priceless.

If you are in socal around the OC area, I will teach you how to fix it.

If you want, I can do it for less than a shop, but there is no way around the top end parts price.  

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5 hours ago, vossman23 said:

You need to jump on YZDOCs offer. Huge opportunity.

You're a good man sir.

OP is only 16, might not have wheels, or be in SoCal. But yah, I've done about 5 over the shoulder jobs, and probably the same amount of repair for others, not many people want to drive 2-3 hours. Although, I did sell a bike to a grandfather 2 years ago in Sacramento, and he contacts me when the bike needs something. I just walk him through it over text, phone, FaceTime. 

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