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99 cr250 top end rebuild

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Okay so I sent the cylinder off to be re-plated and got new piston, rings, gaskets etc. after 3 weeks of waiting I got all the parts back. Now just to put it back together.... I have a general idea how to cause I took it apart. I'm sure there is a topic already on this or just google it but I can't seem to find a video on how to put it back together. So if some one could help me out here it would be much appreciated. Don't wont to put it together wrong lol

Edited by HondaDude21

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The 92 - 01 motors will have the same assembly procedure. Better do a leak down test before you fire it or you could repeat the whole rebuild again.......

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oh boy....

 

there are two ways to do this. Slapping parts back together in the correct order, or building an engine measuring checking clearances torquing things correctly and cleanly.

 

The $20 you'll spend on a manual will be the best money spent of the whole project and itll walk you through everything. valves. gaskets. what to lube and not to lube, but grease. recheck timing even if its right. measuring bore piston clearance. ring end gap. all the right torque values... a torque wrench..! etc.

 

i have many friends that slap their bikes and cars back together. They all come apart, or they have noises, or they are always working on them. My stuff. Solid, but i take 3 times as long building it... i used to be one of them until i got tired of working working working. Cause i thought it was cheaper too. Nope. Working once, right and riding without problems for 10% more cost beats wrenching after every ride.

 

just sharing some experience... by the sounds of the OP you need to hear this.

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oh boy....

 

there are two ways to do this. Slapping parts back together in the correct order, or building an engine measuring checking clearances torquing things correctly and cleanly.

 

The $20 you'll spend on a manual will be the best money spent of the whole project and itll walk you through everything. valves. gaskets. what to lube and not to lube, but grease. recheck timing even if its right. measuring bore piston clearance. ring end gap. all the right torque values... a torque wrench..! etc.

 

i have many friends that slap their bikes and cars back together. They all come apart, or they have noises, or they are always working on them. My stuff. Solid, but i take 3 times as long building it... i used to be one of them until i got tired of working working working. Cause i thought it was cheaper too. Nope. Working once, right and riding without problems for 10% more cost beats wrenching after every ride.

 

just sharing some experience... by the sounds of the OP you need to hear this.

 

 

I agree 100%

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And yeah my original post didn't help me out. Made me sound as dumb as a box of rocks. Which I might be I don't know lol. But I know more than how little I made myself sound like I know. So don't freak out people. Getting it today and pitting it together. I'll get back to you guys and let you know how it's runnin when I'm done!!!

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Well okay guys i got it all back together.... wont start. It has plenty of compression. blows my finger out of the spark plug hole. the spark plug is good. is getting spark outside of compression. And as far as i know it is also getting fuel. why wont it start???? what could be some problems?? I wanna get back out and riding!!!

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Well found out its leaking in the front of the cylinder out the gasket. I've tightend the nuts down pretty good but still Leaking. It take a lot to get a good seal were the cylinder meets the bottom end?

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Well found out its leaking in the front of the cylinder out the gasket. I've tightend the nuts down pretty good but still Leaking. It take a lot to get a good seal were the cylinder meets the bottom end?

 

After you run it you should tighten it again. It's possible that jug is warped from too much heat or previous owner used screwdriver to remove jug from bottom end causing a leak. Look for damage on sealing surface. 

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After you run it you should tighten it again. It's possible that jug is warped from too much heat or previous owner used screwdriver to remove jug from bottom end causing a leak. Look for damage on sealing surface.

does it take a lot of pressure to get it tightened down. Cause if I use an extension it's not to hard to keep righting

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Well found out its leaking in the front of the cylinder out the gasket. I've tightend the nuts down pretty good but still Leaking. It take a lot to get a good seal were the cylinder meets the bottom end?

I ran into this with mine too. I think it's cause I had to buy a new right side case half and the mating surfaces at the seam of the center gasket where out just a hair so I had a pinhole leek right below the exhaust port at the base gasket. The fix for me was to use permatex spray a gasket on the oem gasket, then I used Hondabond on the seams of the center gasket on the base surface if that makes sense, no more leak now... Make sure your using an oem base gasket cause nothing seals better than oem but at least try Hondabond at the seams of the center gasket if nothing else.

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does it take a lot of pressure to get it tightened down. Cause if I use an extension it's not to hard to keep righting

all the cranking in the world won't fix this, it will just cause more problems. You have an issue with the sealing surface and the voids need to be either re surface or the simple solution is to do what I said in the previous post. Worked for me but then again my leak was a pinhole size and I could see 1 tiny bubble coming out like when you get a pinhole in a tube and put it under water. Deck the base and jug to see if you have any low spots in that area with a good straight edge and a feeler gauge if your eyes are not good enough to see low spots.

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