1377 problem

Message

killercrow · #1 Post by **killercrow** » Sun Dec 25, 2005 8:15 pm

hey guys.. my 1377 is losing power and i cant figure out where from... ? i can feel a blast of air in my face when i pump it up to the max, but not under 20 pumps. as far as i know im getting a good seal in the port area. think it could be that the valve stem guide is wearing? with less than 300 shots fired? and im leaking air when i let it sit also... would teflon tape be suffice to seal the valve casing? one other thing, with the pump piston im using, as some of you may remember, its brass with some 90 durometer o-rings (2), im using 100% silicone oil. is this the wrong kind of oil to use? im getting lots of black residue, presumably from the orings... i think maybe its from the oil im using...

what do you guys use in your pumpers? and do you get the black residue?

if anyone has some pointers for me, it would be much appreciated.

al.

Gotrice23 · #2 Post by **Gotrice23** » Sun Dec 25, 2005 8:17 pm

http://www.airgunforum.ca/forum/viewtopic.1711.html

killercrow · #3 Post by **killercrow** » Sun Dec 25, 2005 8:24 pm

yeah i seen that one, but you gotta remember, with a pump air gun, the way that the linkage for the piston is set up, the piston goes slower as it gets closer to the piston... thats using leverage to your advantage, otherwise you wouldnt be able to close the pump arm. ever try to push the piston in without help from the pump linkage? even the first pump is difficult. but... sure it generates a bit of heat, but not 800*. most of the heat im guessing is from friction alone.

Gotrice23 · #4 Post by **Gotrice23** » Sun Dec 25, 2005 8:26 pm

Check the "o" ring, it may be damaged. Same thing happened to my Daisy 880.

killercrow · #5 Post by **killercrow** » Sun Dec 25, 2005 8:28 pm

there no real visible damage... maybe theyre just wearing out. tell me something though, on your daisy, it uses an oring, right? is the groove cut square, or round to fit the oring?

Gotrice23 · #6 Post by **Gotrice23** » Sun Dec 25, 2005 8:29 pm

killercrow wrote:there no real visible damage... maybe theyre just wearing out. tell me something though, on your daisy, it uses an oring, right? is the groove cut square, or round to fit the oring?

I don't know what your talking about, the "o" ring on my daisy seals the air in the valve....I think.

DoctorFrankengun · Sun Dec 25, 2005 10:18 pm

If it is leaking air while sitting there are only three places for the air to escape, the port valve, the "O" ring where the two pieces of the valve body screw together, and the check valve.

Looks like you are going to have to take it apart

Gotrice23 · #8 Post by **Gotrice23** » Sun Dec 25, 2005 10:22 pm

Metalmuncher49 wrote:If it is leaking air while sitting there are only three places for the air to escape, the port valve, the "O" ring where the two pieces of the valve body screw together, and the check valve.

Looks like you are going to have to take it apart

TCooper · #9 Post by **TCooper** » Sun Dec 25, 2005 11:38 pm

My single stroke HW40 uses a 90 durometer o-ring and I use pellgunoil (30W-Non-Detergent oil) for lubrication. My first o-ring lasted over 20,000 shots and never had black residue. Daisy recommends 30W-ND for the 7X7 pump pistols.

Todd

airsmith282 · #10 Post by **airsmith282** » Sun Dec 25, 2005 11:49 pm

leaks when sitting is ususally the valve stem seal is letting go or the inner valve body oring is frying from to much pressure,also the only oil you use on an air gun is crosman pellgun oil or SAE 30 non detergent motor oil, i would not use any thing else my self, the other oil is likely starting to deterate your rings and or pump cup and that could be where the black stuff is comming from as well.. the check valve is also a likey leak area if i remeber you moded that area to flat nose it right.. any how those are my thoughts.....

killercrow · #11 Post by **killercrow** » Mon Dec 26, 2005 2:57 am

well, thanx guys! i figure the mods to the face of the valve are fine... making it flat doesnt affect the check valve seal. maybe the reason for the leak could be the black residue. i guess i'll mess with it til i figure it out

metalmuncher, i have this gun and valve apart at least once a day

doesnt scare me

maybe im wearing it out by taking it apart?

hmm, i'll have to try different oil for sure. does walmart or canadian tire sell it?

DoctorFrankengun · Mon Dec 26, 2005 8:58 am

[quote="killercrow".............. black residue.............

hmm, i'll have to try different oil for sure. does walmart or canadian tire sell it?[/quote]

Black residue is not a good thing :-& It sounds like whatever oil you have been using is eating the rubber.

I would never put any petrolem based oil in an air gun [-X There are special kinds of rubber made for hydraulics that resist disintigration but I doubt the the rubber used in airguns is made of that stuff. Remember that even the rubber seals that are used in the brakes of your car cannot take motor oil. I believe that Pellet Gun Oil is mineral oil. :-k

RM422 · #13 Post by **RM422** » Mon Dec 26, 2005 9:20 am

Air tool oil from nail guns is the best. It's basicly the same as pellgun oil but a lot cheaper 6 bucks for a litre. I have used it on all of my airguns with great success. Fridge turbine oil also works great.

jezX · #14 Post by **jezX** » Mon Dec 26, 2005 10:14 am

i get some black from my pump guns as well . as far as i can tell it's not a problem . just some extra oil . it should stop after a bit . i like to oil my cylinder every time i shoot ,just a bit .

ABshooter · #15 Post by **ABshooter** » Mon Dec 26, 2005 10:40 am

[quote="jezX"]i get some black from my pump guns as well . as far as i can tell it's not a problem . just some extra oil . it should stop after a bit . i like to oil my cylinder every time i shoot ,just a bit .[/quote

NEVER!!!!!! Oil your cylinder every time you shoot???!?!?!?!? I wouldn't do that if I were you...

Killa crow: Pellgun oil comes in a 1/2 oz (or is it 1/4 oz? Can't remember) tube at Ctire, with all the guns and pellets, I'm surprised you have not seen it before. Allthough RM422 is correct, air tool oil works good, a tube of Pellgunoil will last a while, and it has a handy little drip nozzel.