I wonder what happened??????

[kandil]

Hi I want to show you some photos of my Yamaha 25HP 2 strokes I got it on eBay for $350 and I was wondering what did that to it?I Had no pressure on Cly 1 and 70 at #2 that explain why the # 1 Cly was dry and # 2 got wet but it never started!! it seems that it over heated and blow the head gasket. Right now I toke it a part and not sure if I should fix it or keep it for parts?thanks
PS I think that this is what happen when you don,t flush

 

[noelm]

Re: I wonder what happened??????

I don't think not flushing was the cause.

 

[kandil]

Re: I wonder what happened??????

I think I will try to rebuild it just for fun!! but I have some question. the #1 Cly wall has a scratch but when I run my finger over it it feels smooth should I oversize it and that means taking the head to the shop or just use the same size and get the Cly honing head that fit on a drill and clean it? install new piston kit.
2 I would like to find the reason which caused the nicks to Cly #2 so it would not happen again.
PS when I got the outboard it had oil all over it and when I toke the powerhead out I saw the bootom oil hose did not have a clip on it and that it leaks from there

 

[James R]

Re: I wonder what happened??????

Unless you have some experience in the rebuild of two stroke motors you should make it a parts motor. If the job is not done right it would be good money after bad. No telling what else is wrong.

 

[kandil]

Re: I wonder what happened??????

I do have some experience from working on the 2 strokes working with Vespa long ago. I had the pistons out and it seems that some one has changed the #2 Cly before!! and the #1 piston is the original and the rings are stuck to it that is why no compression on it and it found that the #2 Cly is bigger than the #1 just by a fraction so I ordered 2 new 0.25 oversize piston kit and a powerhead gasket and when it comes in I will take it to a machine shop for boring I think it is going to be fine it is oh and I ordered a manual

 

[kandil]

Re: I wonder what happened??????

Here are some photos off the progress

 

[deejaycee_2000]

Re: I wonder what happened??????

hey man i told you to just ask me directly, it is a easy fix, just hoan it, clean up the mess and install 2 new pistons and rings, and it will run like a dream again ....

 

[kandil]

Re: I wonder what happened??????

Hi man how are you? I know you told me but I did not want to bother you!! and I wanted my post to maybe help other do it your self specially in this bad economic time!!

 

[kandil]

Re: I wonder what happened??????

Hello I got my oversize pistons today!! and I noticed that they have 3 rings not 2 is this OK? or did I get the wrong part? thank you

 

[deejaycee_2000]

Re: I wonder what happened??????

no that is ok, if the fit it should be fine, just double check that they are almost identical to the old ones (height, width etc.) .....

 

[kandil]

Re: I wonder what happened??????

OK I got all the right parts for it that was the hard part any way I put every thing back together about 95% that was fun and I just have to hoke the links for the shift and gas and I have some questions that my manual is not good for it!!!!!
1- can I use vacuum hose to replace the dry oil lines?
2- what is the torque on the 6 bolts that hold the powerhead to the mid section?
3-what kind of compression should I get? I am getting 105 on both!! is that good or bad? and is this reading gonna go up after the braking period? this are some photos of the parts and now thank you in advance

 

[kandil]

Re: I wonder what happened??????

Just to update that all links are back changed oil pump hose and she fierd right up like a dream and a nice warm stream of pie

 

[deejaycee_2000]

Re: I wonder what happened??????

awesome, glad you got it sorted .....

 

[jaymz101]

Re: I wonder what happened??????

did you ever figue out what gouged up the #2 like that? Just curious.

 

[kandil]

Re: I wonder what happened??????

did you ever figue out what gouged up the #2 like that? Just curious.

It seems that some one changed the piston # 2 and used the wrong size needle bearing or the same worn out ones when I toke it a part and lined up the 31 needle bearing and the # 2 right under it it was about 1/2 a bearing too small it was the wrong size that is what I think was wrong