Hi all! I'm new to this site and ATV's in general. I've had quite a few motorcycles in my day but never an ATV. My son (who just turned 10) has expressed interest in doing a project with me out in the garage. I thought it would be fun and a good learning experience for him. So as the title suggests, I found a 2007 TRX250EX. The owner seemed honest and said the motor was "blown". He stated his girlfriends kids overheated it out in the field one day while he wasn't home. He didn't know much more than that. It had oil but the battery was no good to turn it over. He had the rear cover plate off so we were able to crank the engine around a few times with a wrench. It definitely had a sticking spot where it seemed to grind a little. My limited knowledge I was hoping it was the top end piston or cylinder. Everything else looked pretty clean. I negotiated a price of $250 and he accepted so I figured I would go for it.
Here's what it looked like when we brought it home:
So we first drained the oil, it was BLACK as night and had small metal shavings in it. Not surprising. So we started taking things apart starting with the top end. Once we got the head off it has a lot of carbon, but actually looked pretty good:
So we proceeded to take the cylinder off and it didn't look to bad either (probably can't tell much from the pictures, but no scoring, heat marks, etc):
Then we ran into trouble. The piston head moves freely but the connecting rod around the crank is pretty bound up:
So here we are now:
I've worked on a lot of things, but I've never taken a lower engine apart. We plan to do it and just go slow and follow the manual. I'm probably going to need a lot of help along the way though. So that's why I'm here.
I guess at this point I would like to know if this is common and if anyone has dealt with it before? I'm curious if anyone has a guess as to why this overheated when there seemed to be oil in the engine. Obviously until it's torn apart no one knows what is really going on, but I'm curious about educated guesses from people who have worked on these before.
We plan to proceed with removing the engine and tearing it open. This is a little intimidating though as I haven't done it before. My plan is to just take our time and ask lots of questions in this thread along the way. Hoping to get some help. So at this point does anyone see any reason not to remove the engine and open it up? Anything in particular to watch out for when cracking this thing open? Again I plan to just try and follow the manual as closely as possible. Also if anyone has any good links to videos of anyone doing this that would be helpful. I search around but didn't find any for this exact engine.
Anyways I'm looking forward to learning with my son and spending time together. I'm hoping in the end we're actually able to ride something and keep the total cost below the worth, Thanks for reading and I looking forward to chatting with you all!!
Here's what it looked like when we brought it home:
So we first drained the oil, it was BLACK as night and had small metal shavings in it. Not surprising. So we started taking things apart starting with the top end. Once we got the head off it has a lot of carbon, but actually looked pretty good:
So we proceeded to take the cylinder off and it didn't look to bad either (probably can't tell much from the pictures, but no scoring, heat marks, etc):
Then we ran into trouble. The piston head moves freely but the connecting rod around the crank is pretty bound up:
So here we are now:
I've worked on a lot of things, but I've never taken a lower engine apart. We plan to do it and just go slow and follow the manual. I'm probably going to need a lot of help along the way though. So that's why I'm here.
I guess at this point I would like to know if this is common and if anyone has dealt with it before? I'm curious if anyone has a guess as to why this overheated when there seemed to be oil in the engine. Obviously until it's torn apart no one knows what is really going on, but I'm curious about educated guesses from people who have worked on these before.
We plan to proceed with removing the engine and tearing it open. This is a little intimidating though as I haven't done it before. My plan is to just take our time and ask lots of questions in this thread along the way. Hoping to get some help. So at this point does anyone see any reason not to remove the engine and open it up? Anything in particular to watch out for when cracking this thing open? Again I plan to just try and follow the manual as closely as possible. Also if anyone has any good links to videos of anyone doing this that would be helpful. I search around but didn't find any for this exact engine.
Anyways I'm looking forward to learning with my son and spending time together. I'm hoping in the end we're actually able to ride something and keep the total cost below the worth, Thanks for reading and I looking forward to chatting with you all!!