Gen 4 Question Poppit....

[Slimpikins976]

Im rebuilding a friends Gen 4 infamous, and I have deduced from the leak it is the cup seal or the poppit. I took the pressure down to 0 in the LPR and the leak was still coming from the hole that is in front of the ram area. So I have deduced it is again the poppit. I ripped that sucker open and BAM !!! pulled the poppit out and it is brass.... way diffrent then the one in my Alias. I did some readings on the boards here and found that in one article it said the Poppit has 3 orings....
this one only has two. one all the way on th rear, one on the front but I can clearly see a space for a third o-ring.
It looks just like the same size o-ring will fit it as is on the back of the poppit so I am going to try this. But my question is do I want to apply Dow 55 to it or just regular old Dow 33? I do not know If we want it to seal, and ill look and read some more I am sure there are posts on this.
I just wanted to see a picture of the correct set up if anyone was so inclined :D thanks in advance ..

[outrageous]

D55 swells them slightly. I'd put a little bit on it and wait 12-24 hours and put air back in the system to make sure the swelling has occured and it should be good if that oring was the problem.

[Toto8]

Apply a light coat of dow55 on front and rear oring keep the middle oring dry no dow this will keep it from blowing off.

[android17ak47]

Yes, there are three orings. Is this what you wanted a pic of?

http://i97.photobucket.com/albums/l224/android17ak47/100_0532.jpg

[Slimpikins976]

AHHHhhhhhh... Sweet I put a little dow 55 on all 3 o-rings shot the gun a few times leak fixed untill I shoot it about 7 more times and the hiss again.
I am going to take this bad boy down and do as you guys said just lube up the front and back o-ring leave the middle one dry and see what happens, in the event I did blow that middle o-ring where would it show up?
I just want to make sure that the o-ring will not get lodged in some other portion of the guns airways. Or does it just blow out and shoot out of the bolt area? i'll report what I find in a few ........

[crankwalk]

Everyone provided great information on this. Its absoutely correct that you only lube the front and rear o-rings and leave the middle dry. This keeps it from rolling off the poppet.

If the o-ring did fall off I believe it would just sit in the poppet area and probably gum up the poppet movement unless it was forced into the ram sleeve, but I don't know for sure. Let us know if it rolled off and where it ended up if so though! :D

[Slimpikins976]

Well fortunately for me the gun was only shoot about 10 times after the hiss began again. I popped this bad boy open and hook off the poppit assembly and indeed the middle o-ring on the brass poppit had slipped off.
Lucky for me it was not blown threw hte gun or lodged into the ram sleeve. I swapped it out with a fresh o-Ring and wiped the old one down and put it in my kit to dry off. reassembled the poppit, slapped it in the gun and let the lpr all the way out and gassed it up.
At first a small hiss, but at around 50 Psi the hiss stopped and it seemed to fix it's self. I dry fired it about thirty times the hiss is almost completely gone. There is however a tiny hiss still, but nothing you can hear unless your ear is inside the the placement for the bolt.
Close enough for government work !!!! thanks so much guys !!

[crankwalk]

Hey glad that worked out for you. Now for the other hiss.. have you changed your ram o-rings? that's usually a main culprit for hissing.. although with all the troubleshooting you've been doing you probably already gave the whole gun an o-ring overhaul right? :)

[Slimpikins976]

Aye the ram tube is the first place I look generally speaking with leaks.
I placed my finger( Pinkey.. the rest of mine are to fat for the bolt area) in line and covered the poppit area...
Small amount of pressure there, and finally the pinkey over the ram area... no leak there. So the hiss it is very small is still coming from the poppet area.
Noting to bad like I said before, and this is a friends gun I teched for him. He had never opened his gun up before so you could just imagine the amount of paint I had to clean out of this gun lol!!! its spotless now and the is is tiny, only thing I could think of would be to change out the poppit, but I don't have any spare Gen 4 brass poppits lying around to try my hypothesis. And I don't want to tell him to buy something that he might not need.

[crankwalk]

Ah I see. Perhaps from all the time your friend had it and never took it apart to lube it, maybe the poppet scratched the surface of the sleeve/valve area and so its not sealing as it should. You can try one last thing, take the o-rings off that require dow 55 on them. put some dow in a little zip top baggie and put the rings inside with the dow. Let it sit overnight so they really soak, and hopefully they will swell enough to seal with whatever imperfections might be in the marker.

[android17ak47]

Ah I see. Perhaps from all the time your friend had it and never took it apart to lube it, maybe the poppet scratched the surface of the sleeve/valve area and so its not sealing as it should. You can try one last thing, take the o-rings off that require dow 55 on them. put some dow in a little zip top baggie and put the rings inside with the dow. Let it sit overnight so they really soak, and hopefully they will swell enough to seal with whatever imperfections might be in the marker.

This is exactly how my EBPRS went bad. The poppet scratched the insides of where the large oring seals the hp air to keep it from entering the ram sleeve. This caused massive lpr spikes, and I could never seem to figure the problem till I took the sleeve out, and made the disturbing discovery that there was deep scratches on it. They were deep enough though that I could never use the ram sleeve again.

[Slimpikins976]

ok Problem arose again.
I am convinced I am either using the wrong size o-ring or the Poppit is bad. every time I re-adjust the gun it runs fine ( UNTIL it is shot without paint.or a barrel squeegie in the way). Its flawless with paint but the pressure of shooting it without paint or the squeegie the leak occurs immediately I degas the gun pop her open take out the poppit the o-ring slid off. Reposition it seal it up fine ... until its dry fired !!
So I am convinced it is the O-ring or the poppit. No groves or slashes are observed in the ram sleeve.
So .... are the poppit o-rings similar or different for gen 3 and gen 4's if they are im going to feel really silly !!! thanks in advance guys...

[crankwalk]

which o-ring keeps sliding off, the middle?

[android17ak47]

Also be sure your dwell is not low. I receantly found out that using too low of a dwell on a gen4 actuallu affects the poppet in strange ways I never thought it would before.

In fact someone said they thought for sure it was a low dwellprob, and I thought that was silly, becuase I am usew to a gen3, and a low dwell would only cause probs like fsdo, low velocity, but nothing to do with leaks, ect... For me it was causing weird prob like reacting diff when using paint, no paint, exactly what you have described.

BTW the 2 larger orings on this poppet are tyhe same size. I believe a .010. None however are the same size as what is used on a gen3, all are bigger. And as for my dwell prob, I was trying to make it work on 6ms at first. 10ms got rid of all my prob, and actualy made it quieter, and more air efficient.

[crankwalk]

If the middle o-ring keeps sliding off to no avail and you're using a 010 sized ring as android posted above (this is the same size ring as the brass nut or pin valve base in your regs on previous Gen Timmies) then try stepping down to an 009 ring for the middle, its been recommended in the past to try and solve the o-ring slipping off problem. Ask your local pro-shop for one, they should have that common size.

[06eviltimmy]

I have the exact same poppet as slim with the 3 o-rings and my timmy was also leaking and i discovered it had fallen off. those 2 o-rings in the middle and the head of the poppet are both 010? if so then i need to grab alot of them. my timmy is leaking down the barrel and when i press down on the bolt the pressure doesnt change. ram orings are fine but the poppet cup seal oring seems to be the problem here. after i replace those poppet orings is there anything else i should replace or look for before putting her back together?

[fprandy]

I found out the hard way, there are some serious size differences in different brands of o-rings. I bought a few that were seriously undersized.

The problem you're having is identical to what I had on a couple of DM7's that just never seemed to seal correctly, and when they did, next day the leak was back. Problem fixed with different brand o-rings.

For timmy o-rings, I would go to Crankwalk. I bet he can set you up.

For larger quantities on Dye guns, I buy from Air Oil products. But, I don't say they would work on BLAST http://www.aoptec.com/oringsonlinefset.htm

[Slimpikins976]

Great advice guys I am going to get another set of O-rings from Crank and slap them on the gun and run with it.... Thanks so much guys I'll keep you informed and post up with any new issues Holla !!!!

[crankwalk]

those 2 o-rings in the middle and the head of the poppet are both 010?yes that's correct they are both the same size