Jump to content

Pistion movement


Recommended Posts

Today, I took my noss head off to inspect the cylinders walls. After looking around and cleaning off the pistions and stuff. I noticed that the pistion would rock back and forth. I thied to muesure it and got a gestament

of .020 thousnds. Is this normal.

 

I rember some one saying that the pistion can rock back and forth when doing a squish test. or sompthing like that.

 

I said in a preavies post that it had a 185 psi in the cylinders. I cant see that being posible with the movement in the pistion now.

 

Also are the cool head o-rings kits the same for the noss head? Or was that sompthing elce.

 

After having 2 Banshee's for a wile now. I think that I should change my screan name to Brokeassmofo :sweat:

Link to comment
Share on other sites

pistons are capable of moving side to side and forward and backward and you will usualy have a very small amount of play ( i think 4 thousanths overbore from actual piston size at crown) around the piston but too much will end up with excessive piston slap in the bore and end up with a broken skirt on a piston. look at the skirt's on your pistons through the intake and exhaust and see if there all marred up. a little scuffing is ok but excessive wear marks and gouging is bad...you definatley want no up and down play in the crank and wrist pin bearings but if you have excessive play forward and backward it's only a matter of time till you bust a skirt...

Link to comment
Share on other sites

A Banshee can have eccessive cylinder to wall clearance and still have full compression. If you remove the cylinders and measure the pistons you will probably find they are deformed and need to be replaced. If you run the pistons too long there is the risk of breaking the skirt off from piston slap or scuffing the cylinder walls and needing a rebore verses just new pistons.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...