29mm seal disk/o-ring problem

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Ray Dunakin

Well-Known Member
Jan 9, 2003
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I've got a weird problem I've never encountered before. I was trying to assemble a 29mm I-210 Redline. This load uses the metal seal disk w/o-ring. The o-ring seemed kind of loose on the seal disk. I had a heck of a time getting the forward end of the liner (with disk installed) into the motor casing. It went in part way and jammed. The o-ring is broken, and lodged between the liner and casing. The seal disk just fell out. Now I can't get the liner out!

Has anyone else had this problem before? Any suggestions on getting the liner out without destroying it??
Can the o-ring be reached with pliers or something to pull it out? if not, put some vacelline inside the case where the o-ring is and liner is, use an candle and heat up the area were the case and o-ring is... you don't want to get it too hot... just hot enought to make the vaciline flow... some should get underneath the liner and o-ring. Then before the case cools, grab the case (with gloves of course) and liner.... and YANK.

You should give Aerotech a call... they should send you a new liner... and most likely, you will need a new o-ring anyway...

Oh... and you did you the seal disk o-ring? not the nozzle o-ring? The nozzle o-ring has the same thickness... but a larger diameter?
Well, I got the liner out, but still ended up chipping a chunk off the end of the liner. And this morning I found out what caused the problem... There was already an o-ring on the seal disk! I always remove them when I clean the hardware, but this was a motor that I'd bought used, and the previous own had left the o-ring on the disk. Black o-ring on a black disk, pretty hard to see without really good lighting. Still, I'll have to pay more attention to that in the future.

Oh, and Gary at Aerotech has graciously offered to replace the liner.
Ray...sounds like you got it solved, but not without some effort. I am with you, I always forget to take the old rings off those seals and wind up cleaning them right along with the seal disk!