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What does this motor need

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Hello I have a 2004 crf150f and I'm pretty sure it blew a ring it was running fine, then I was riding up a hill when it just died I got it started but it was super ruff it blew a lot of smoke and it would not stay running. I took the motor apart and I don't know how to tell how bad a engine is so could you guys tell me what this engine needs?

 

 

Ps, after removing the cylinder looks like the piston ceased IMG_1522.thumb.JPG.e5c943e53d06edae5ca2a874631c5f8e.JPGIMG_1521.thumb.JPG.05c58b6cadf8efaa23d96a38d361fd12.JPGIMG_1523.thumb.JPG.4ed1943e6d144ce5e3f9bc33202f1a9b.JPG

 

IMG_1529.thumb.JPG.e306e1b8fd559f02c2990282274b55c9.JPGIMG_1525.thumb.JPG.35513d6378619baa64608d1695aea6f1.JPGIMG_1528.thumb.JPG.1fc3e850278146f7902e55418f8bd89d.JPGIMG_1526.thumb.JPG.d2390bac20b3736045417aa859847e5d.JPG

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Looks like it's been sitting with a cylinder full of water at some stage. 

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Agreed. Cylinder full of rust damage from sitting with water/moisture in side. New piston/rings/hone bare minimum is required.
Next Oversized piston would be ideal, recommend valve job and valve stem seals while your in there also.

I recommend to use all OEM Honda parts but if you go oversized bore/piston, the piston kit may need to be aftermarket?
(ProX or Wiseco)

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I would start using a much better fuel as well, there is a lot of build up in there (plus where did all the water come from, is there a water leak or was it in the gas or was in blasted in with the jet wash, did it spend some time in the river) a better quality gas with more detergent in it would stop a lot of that developing.

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Athena big bore cylinder kit from eBay is the best deal going for a complete , ready to install kit... 

Bigger bore and higher compression... 

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Nope... You are right Steve...

I have a problem of only thinking about crf230's when I'm on this forum....

Thanks for correcting me!

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On 10/22/2018 at 9:22 PM, SkipD said:

I would start using a much better fuel as well, there is a lot of build up in there (plus where did all the water come from, is there a water leak or was it in the gas or was in blasted in with the jet wash, did it spend some time in the river) a better quality gas with more detergent in it would stop a lot of that developing.

I don't think fuel is to blame for any of this. This was long term rust. Next oversize piston and bore needed. Check your valves and guides while at it. 

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On ‎10‎/‎24‎/‎2018 at 10:59 AM, sbest said:

I don't think fuel is to blame for any of this. This was long term rust. Next oversize piston and bore needed. Check your valves and guides while at it. 

I was not saying that fuel was, I was saying that the build up in there on the valves and head would not be so bad with better fuel. The other question was where did the water come from that needs to be identified as well. 

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16 hours ago, SkipD said:

I was not saying that fuel was, I was saying that the build up in there on the valves and head would not be so bad with better fuel. The other question was where did the water come from that needs to be identified as well. 

The carbon build on the valves and head look pretty normal for a lightly driven old 4 stroke. If it was run harder and hotter the exhaust valve might have been more white. The rust looks like storage condensation to me. Cool moist night air fills The cylinder and condenses in beads on the wall. Some of it trickles down to the piston and sticks there, trapped by the rings and by capillary action. No angled high water mark so this did not happen by rain water leaking in, or by a dousing. The condensation beads can be seen in the upper cylinder. The piston may have been moved a couple times, but this motor set for a long time and has not run much since being restarted, or we would see it in oil deposits. There is a story there, if you know how to read it. 

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