Changing a Piston

Ask Pete at Pittsburgh Power, he'd know. I've never weighed pistons, just threw them in and hammered down. Did change one only, one time in a Cummins Big Cam with 250,000 miles on the others, ran fine.

 

I've never had a problem with reman, however, I only have run genuine Cummins Recon, as I run Cummins, not Detroits.

 

http://pittsburghpower.com/

 

Just change the bad piston and be done with it. You are stressing over nothing. The other pistons are almost new, so why would it be bad to only change the one? Get a head, make sure everything is right this time, and go for it. Changing only one one piston has been done for many years.

 

Get the head you have to machine shop for evaluation before you purchase another one. Yours might be OK, and would save a pile of $$,

 

And if you do change 6......and want to balance.......weigh them all individually and balance to the lightest one with a drill. If you want i'll get a picture and show you where to drill. ( Gots to be careful )

If you want we can talk valve performance, seat angles and flowing the head...... maybe get a lil more from the 12L? Hmmm? Pinch her in the butt a lil?

To be fair tho, the last Yamaha I kicked in the butt had a blower and was a 2 cycle. ( Did plenty of cars tho )

 

With two piece pistons, just swap tops with skirts, till they get a good match. Heaviest top with lightest skirt, on down the line. Saves drilling.