almost done with rebuild but i have a question

[Cory9584]

When i tore the engine down the right side piston and dome was melted and the rod on the same side was very loose. Now im wondering what caused the piston and dome to melt? I sure dont want to do it again. Can it have been from the bad rod? If you look at the piston theres little chunks melted off it.

[theshee]

hard to say, could have had an air leak on that side, leaned out and melted it.

[Cory9584]

I hope i can figure something out so i dont have to worry about it

[Washburn]

What do your plugs look like?

[grady7633]

I have seen a similar situation with an o-ringed cool head that didn't have the o-ring seated properly. Bike ran great until head leaked enough air into the cylinder to melt a hole into the top of the piston, also melted the cylinder wall where the leak was located.

[Cory9584]

The plugs look clean, but when i first got the bike i decided to start it to test everything and it backfired and shot a big flame out that pipe

[theshee]

i bet one cylinder was full of gas. Messed up the rod when tou kicked it.

[Cory9584]

it turned easy though, not to mention i think the last owner rode it for a while like that

[Cory9584]

how do i do a leakdown test once its done?

[theshee]

how do i do a leakdown test once its done?

 

search posts by rnbrad, he has a leak down topic. you will need a leak down tester too.