Need Help Again

[dnoftz]

ok so got my new piston today. Its 60 over so like 67.45. Installed it fired it up and it purred like a kitten. sounded good. Did my 3 heat cycles and after letting it cool I went to do the first break in ride and it seized. Any suggestions on what might of happen?X(X(X(

 

[Quadrider10]

maybe too lean. did u do heat cycles corectly?

 

[Awk08]

did you measure piston to cylinder clearence ?
did you leakdown test it ?

 

[dnoftz]

did you measure piston to cylinder clearence ?
did you leakdown test it ?

To be honest. I do not know how to measure Piston to cylinder Clearence. So I took it to a local shop and had them gauge it and went by that.

As for leakdown. No We made one but it did not wont to work so the answer is no.

 

[Awk08]

i'm guessing a major airleak caused the leakdown tester to "look" like it wasn't working, and also fried your shizzle

you MUST leakdown test

 

[dnoftz]

Im going to tear it down tomorrow and see what it looks like

 

[Blaaster]

No leak test gets a smacked wrist, or a punch in the wallet, or both!

Did you re tension the head and jug?

What pipe?

What jetting?

What oil?

What ratio?

 

[dnoftz]

No leak test gets a smacked wrist, or a punch in the wallet, or both!

Did you re tension the head and jug? Not sure what you mean by tension. Did tighten the jug back to spec

What pipe? Running stock

What jetting? Stock

What oil? Pens

What ratio?

50-1

I did get it apart and not sure what was going on. The piston is fine the rings are fine It slid off easy. The cylinder looks fine. It felt like it was tying up. even when I tried to turn it over by hand I could feel tension like it was locked up?

 

[Blaaster]

In my opinion 50:1 is not enough oil foR breakin.

32:1 is the prefferred ratio.

 

[borednstreched]

if the cylinder/piston/rings look fine. then it could be the wrist pin bearing or rod to crank bearing over heated possibly, that could be causing the bind. check them over. if they or the ends of the rod have a gray or white heat soaked look, they are dead most likely. what color is the plug that was in there? at least you didnt hit detonation.

 

[toytech]

possible crank and rod bearings seizing.

 

[Blaaster]

Are you running oil injection and pre mix at 50:1 in the tank at the same time.

If you are you could be overheating due to a lean mix.

Some fools promote the running of extra oil in the tank for break in, this is a no, no, as it messes with the air fuel ratio and can cause the motor to seize.

 

[brandoz28]

did you check the torque on the head and base nuts between cycles