Who yellow tags pistons ????

[gjordan]

I know I have discussed cleaning pistons before, but are there any recommendations on who to send them to for inspection, and certification? Grant.

 

[Dan Cullman]

There are a lot of variables in determining the airworthiness of a piston. I have never seen an 8130 applied to a used piston. It may cost $$$, but usually new pistons are available for current and popular out of production engines.
As far as Franklin pistons go, I generally clean and weigh them before sending them off for zyglo inspection. Most propeller shops have that capability. I have a couple dozen Franklin pistons being inspected at Northwest Propeller at this time. When you get them back, you can check them dimensionally.
Dan

 

[gjordan]

Thanks Dan. I also had never heard of yellow tags on used pistons, but I thought I might have overlooked it. When I get the time (I am moving right now) I will clean them and send them out for Zyglo. Grant.

 

[Dan Cullman]

Yesterday, I actually had Northwest Propeller offer 8130s for the 26 Franklin pistons I sent in for zyglo.
However, all the paperwork would say is they had been NDT'd for abnormalities....read cracks. This is the same disclaimer that A/C Specialties uses on many of their 8130s. It is up to the overhauler/rebuilder/inspector to ensure the part meets manufacturer specifications for airworthiness.
Dan