TargetTalk

IZH 46m valve has been leaking. I can hear air wheezing out of the transfer port after I cock it. No amount of oil is fixing it.

Has anyone tried the valve upgrade kit from mac 1? I believe the smaller o-ring replaces the #31 seal. But what is the larger o-ring for in that kit?

http://www.mac1airgunshop.com/izh-46-va ... 46ss90.htm

I don't have any experience with the MAC kit. I'm guessing you stack the O-rings, but that does seem weird.

Replacing the seals from the front typically requires removing the compression cylinder, which is a bit difficult. It usually requires heat, you need a way to hold onto it that won't distort the tube, and you have to re-install it so that everything is aligned properly.

This thread has some info about seal replacement, including how to go about it from the rear:

http://www.targettalk.org/viewtopic.php ... ck#p214944

I've made one of the seal replacement tools, but haven't had a chance to try it out yet. I had an email discussion with someone who used this approach successfully without making the tool. I think they found an appropriate sized ball point pen to use as a seating tool.

I had my 46M Mac tuned a while back and am very pleased with it.

If you charge the cylinder, and it is not holding air, it is the piston valve. That is relative easy to change. Much discussion on the internet.

If you can charge the cylinder, but it leaks when you close the breech lever, it is the inner breech valve.

I had to change the inner breech valve awhile back, it is a lot of fun :(

Doug White 's drawing was instrumental in helping me changing that inner breech valve. There is really no discussion on how to change that valve on the internet. Doug's drawing is the closest thing to "a discussion". I can't really recall how I got that valve replaced. You will venture into an area not many people entered. Even Doug with his explicit drawing did not venture into that area. You might not be able to put the humpty dumpty back together, that will be a real problem. I remembered I had to tie a string to a screw. Screw the screw into the inner valve, then pull it out from rear. That was the fun part. But the toughest part for me was getting the stem valve and bush out. That was a nightmare, with a lot of cursing involved.

Good luck.