I bought a Parker "51" aerometric from someone and began to experience hard starts with the pen after about a half hour of the pen being capped. I contacted the seller, who offered an immediate refund, but I didn't want to part with the pen. I took the cap off my Hero 616, put it on the Parker 51, and the hard starts went away. I checked the pen cap for a cracked inner cap and all looked good.
The seller offered to send me another cap. I put the cap on the pen, and it immediately began to hard start. But with the Hero 616 cap, it does not.
The seller tested the second cap in a 51 and did not notice any hard starts.
At this point, I am thinking it might be the clutch ring on the pen not forming an air tight seal with the cap.
New clutch rings look pretty cheap, so I am wondering whether I should swap the clutch ring out, or is it better to just return the pen in case it's not the clutch ring.
Also, would a Hero 616 clutch ring work in a Parker "51" ? I figure since I have a 616 just lying around uninked, I could cannibalize it for parts.
Edited by apastuszak, 31 May 2017 - 00:11.