Forearm wobble on 1377

[chinaboy]

I replaced my forearm 1377 with a 1389-010 from the 1389.   Now that it is on it wobbles a good deal.  I'm thinking of putting some washer in between the forearm and the metal piece.  Does anyone else have this problem or did I do something wrong?

[1377x]

I replaced my forearm 1377 with a 1389-010 from the 1389.   Now that it is on it wobbles a good deal.  I'm thinking of putting some washer in between the forearm and the metal piece.  Does anyone else have this problem or did I do something wrong?

you do have the roll pins all the way through the forearm right?

[1377x]

you know,now that i think about it
i did have a 1377 that happened to
i cut a soda(cola) can into little strips,wrapped them around the pump lever "U" shaped put the forearm on
kept building up the soda can "U washer" until the wobble was gone
then i took a sharpened tipped nail poked a hole through the can washer and then installed the roll pins
hope this makes sense
i can take some pics if necessary

[breakfastchef]

There will be inherent sloppiness of the forearm linkage. Try gently prying apart the two metal leaves (see 760D043 in the diagram). This will help to reduce some of the play and wobble.

[chinaboy]

Thanks for the suggestions.  I think I will try a combination of both adding "U" shaped washers and prying the metal apart.  Both make sense.  I am on my first build and learning still.   I just installed my FT piston and valve, 20" barrel and pump pin yesterday. 

[Crosshairs]

I just spread the linkage arm and that works fine for me.
                                        Mike

[quickster47 †]

Depending upon the quality of the parts your gun has, spreading the linkage arm usually works to tighten things up.  But if you got some really sloppy parts you might need shims.

Carl

[1377x]

Depending upon the quality of the parts your gun has, spreading the linkage arm usually works to tighten things up.  But if you got some really sloppy parts you might need shims.

Carl

thats what we call them
i was saying soda can washers when i should have been saying shims
i had a brain fart
next time i have an isue like this,i will try speading the linkage first

[NorthStaR]

i had a brain fart

Everytime I read that phrase I pee myself!      What with that and sloppy parts! 

Good fixes all round. 

[Make MY day]

I'm finding that on the forearm where it connects to the tab on the bottom of the receiver when closed, has either worn down or the tab itself has worn and the forearm does not always stay in closed.  Had dropped down on it's own a few times.

[1377x]

I'm finding that on the forearm where it connects to the tab on the bottom of the receiver when closed, has either worn down or the tab itself has worn and the forearm does not always stay in closed.  Had dropped down on it's own a few times.

are you using a flat top set up?

[Make MY day]

This is stock.

[1377x]

i have a worn pump arm but it wasnt the problem for my arm opening
a worn out pump cup was the problem

[Bentong]

Try C. Mellon, he got some anti wobble stuff
http://mellonair.myfreesites.net/web_images/100_0156.jpg
http://mellonair.myfreesites.net/web_images/100_0117.jpg

[1377x]

i think the op is saying the pump arm is wobbling not the pump lever
it is a good suggestion to use a the mellon solid pin i dont think it will stop a wobbling pump arm though