Defiant rebuild

[BreakfastB33rs]

So after getting back in to the game after a 20+ year break I got a few great days out with this Defiant. But I noticed that the LPR adjustment has become very picky and trying to get velocity without a leak down the barrel has basically become impossible. So after reading through some amazing resto threads here and on the ICD page I started to pick my way through mine replacing o-rings and giving everything a good lube.

After getting it back together I still have a pretty good leak down the barrel so I pulled my valve out and gave it a polish following Myrkul's steps. I also flipped the cup seal over assuming that it's omnidirectional but still have that pesky leak.

The only think I haven't done is break into the ram assembly (I seriously have no idea how you guys are getting the back end of that thing off) could this be the cause of my barrel leak? Or am I missing something about the valve (maybe more polishing?) and cup seal?

Thanks in advance!

[Trbo323]

Did you pull the valve body out and replace the body o rings?

If the leak changes when you adjust the LPR then it can't be the valve. No LPR air goes through the valve. I would look at the ram, my theory is the ram is leaking and the air is coming up through the cocking pin channel and following the bolt to the barrel.

Pull the bolt out and air it up, put something down the cocking pin channel and see if that disturbs the air flow, that should tell you if it is (likely) coming from the ram or not

Sent from my motorola edge 2024 using Tapatalk

[BreakfastB33rs]

I did replace the o rings on the exterior of the ram body, but haven't been able to crack the back off the ram to change the o ring on the inside yet. But starting to sound like that's what I am gunna need to do.

[Myrkul]

I'm definitely leaning towards it being an issue with the ram, the valve and cup seal look fine. The back cap should just unscrew, usually they are only finger tight. You might need to use pliers. The hammer and ram shaft will likely need a torch to break the red loctite, but the back cap should be pretty easy.

[BreakfastB33rs]

I think I am gunna need to find someone with a bench vice, I've been at the back cap with two counter rotating pliers and haven't gotten anywhere yet.

[Myrkul]

I almost wonder if some yahoo loctited the back cap of the ram on yours. I've never once had an issue with the back cap....maybe just torch the whole damn thing and then give it a go again?

[BreakfastB33rs]

I bought it new from Bob's shop and didn't even realize the back cap was a separate part until going through these threads. I've definitely done some regretful loctiting but this isn't one of those cases.

[BreakfastB33rs]

Wow, thanks for all the great feedback! I had a feeling there was something up with those 015s on the pistons, I'll give the tank o-rings a try or order up some 90 durometers.

I had a little free time yesterday and went to my local shop (Critical Pursuit Games) and Dane made a great observation which is obscured by the HRP adaptor in the picture above, but when I put the valve back in sent it a little to hard on the lock screw and actually pushed the valve out of center. So I backed that screw off a bit and moved the valve around just to help the o-rings re-form, and now I am down to just a little breath of a leak down the barrel.

Maybe that's as good as its gunna get for a 25 year old marker but it does seem that if I give the bolt just right little wiggle I can get the leak to stop. Oh, and on air up there is no leak, so it only starts after the first shot.

And one more thing, maybe this can be explained by the wrong durometer o-ring but in a string of shots I will get one or two that are "weak" the bolt will do its full travel but doesn't seem like there is proper air behind the shot.

[Frmrspec]

Definitely sounds like RAM rebuild time

[Myrkul]

I am down to just a little breath of a leak down the barrel.

Maybe that's as good as its gunna get for a 25 year old marker but it does seem that if I give the bolt just right little wiggle I can get the leak to stop. Oh, and on air up there is no leak, so it only starts after the first shot.

That's almost definitely the ram then, especially if it doesn't leak on air up and only after the first shot. If you zero out the LPR after the leak has started it should go away, then start back up once the LPR is turned back up.

And one more thing, maybe this can be explained by the wrong durometer o-ring but in a string of shots I will get one or two that are "weak" the bolt will do its full travel but doesn't seem like there is proper air behind the shot.

Either a reg is sticking or a reg is creeping. I definitely suspect the LPR is the culprit. Keep a close eye on the gauge, that should tell you how the HPR is doing. If it's holding a constant pressure and recharges quickly, it's working and we can focus on the LPR.

The regs on these are really their biggest weakness, they aren't great and are pretty fussy. You can get aftermarket LPRs still but they are a little pricy.

I would message Araphel and see if you can get a few new regs seats he made if you do want to try to use the stock regs. You'll likely need 2, one for the HPR and one for the LPR.

[BreakfastB33rs]

I've had the ram soaking in PB blaster all weekend trying to get it apart and still no luck on getting the back cap off... Starting to wonder if anyone has a lead on an extra back cap or even a whole new ram. I am not feeling very confident about getting that back cap off without totally destroying it.

[BreakfastB33rs]

Huge thanks to Myrkul for reaching out to me with an offer to help! I sent me ram off and he was able to get it cracked open. I guess at some point along the way the oring at the back of the ram was removed and it was just loaded with red Loctite so that it would seal up. There is a chance I am responsible for this total disaster, but I don't remember (I've got a pretty good memory for this kinda thing) but I don't think it was me. I did buy it new from Bob's shop as I may have mentioned who knows if IDC did this during a build or they just ran out of the right size oring at Bob's when I had brought it in for service but who knows?

Myrkul did awesome work! The business end of the ram now shines like a mirror and there's not a hint of leakage!

I loaded it up in my defiant and got a few great shots out of but now I am running into a new issue. With HPR set to between 350-400 psi and LPR a half turn backed off from leaking I am just getting a little puff of air sound from the solenoid now. I haven't had a ton of time to mess with it yet, after letting it sit a while I gassed it up again and got a few shots then back to just the little puff...Is my solenoid giving up the ghost now?

Attempting to cycle the marker video:
https://youtube.com/shorts/O3b7dEHsaKY?feature=share

[Myrkul]

HPR is WAY too high. You have too much pressure in the valve for the ram to open it. Drop it to 275 and report back. These should be running 180-300 PSI on the HPR. I've almost always needed to swap to a weaker valve spring as well. I recommend the SLPS autococker valve spring, but most lighter autococker springs "should" work, but the SLPS spring always works perfectly so that's definitely my recommendation.

Also keep in mind, I've never seen a gun hit the lower end of that range without either Zenitram or MacDev parts, most noticeable is there vert ASAs, but I guess the valve makes a difference too (not as much as the vert ASAs).

LPR is too low as well, it should be a quarter turn back from causing the solenoid to vent, not half a turn. That should give you around 95 PSI. If everything is optimized you can get the LPR lower, my personal best is 60 PSI, but the ram needs to be broken in, you need an aftermarket valve, spring, and vert ASA and a modded bolt with a freak to get them that low. With the stock 3/16 airflow hole coming out of the top of the reg there just isn't enough juice to run it much lower.

Edit: After watching your video...stick a fresh battery in there. If it's still not going, drop the tray and try hitting the "Manuel" white button on the solenoid and see if it goes pop. You should be getting something out it, it doesn't even look like it's trying which almost always is a battery issue.

[BreakfastB33rs]

Ok, I'll check into the valve spring swap. I get the same result of just a small puff on HPR from 150-300.

[BreakfastB33rs]

Haha yep, it was the battery, so nice when its that easy of a fix!