Motor metal pinion troubles and hk416 tappet return spring size

Hi guys,

in hk416 tappet return spring broke, thing is i threw the original out, thinking they were all same size,
now balls dont feed to well, so

i was hoping anyone could send me a pic of what their hk416 tapper return spring looks like please, as i dont know how far down to cut my spare to.

Also had to replace nylon head of motor as it bore out, with a metal one.
When i tried to put it on ti was so stuff, had to use a hammer to get it on properly, but now i think i may have hammered in that inner pin down to far. as it dosnt seem to be the right length.
Can i post some pics and show you guys, i hate the idea of having to throw out another motor just because the nylon head broke. Thanks


someone else will need to provide the spring assistance, but no, they are not all the same and every mm has an impact

the pinion head…would only really chew out if your bevel mesh were not set correctly. i suspect you have a larger issue here on the outset

on the hammering…yikes…probably a dumb ar53 question but…you did remove the grub screw from the pinion before hammering?

getting pinions off…i use some pin pliers to lever them up gently noting that i don’t lever against the can itself but a piece of wood so as not to damage the motor can.

others have converted chain link pullers which is a neat solution.

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Or you could just use the right tool :+1:


i could… :stuck_out_tongue:

but i don’t

niggz has to eat ya know :stuck_out_tongue:


Food is over rated, it wastes far to much money that could be better spent on blasters :joy:


wholly agree

but i find if i’m not eating than i’m cannon fodder

its a performance thing

and i don’t like being shot


OMG your starting to sound like my wife :zipper_mouth_face:


there will be no reciprocal action here m8…


See ! Just like my wife :eyes:


if i ever have to get on my knees for you on the field…ur getting it alright…

but maybe not quite how you like it



Again ! Promises promises :hatched_chick:


thats a good question eh…well the one in my head is…

beside hiroshima i don’t know who’s local to me or where they play…

you can’t hide beyond anonymity forever…

the tyranny of distance though…that might save ya


Excuses pfff !!


Oh I couldn’t take a full day of complaints…
Your blaster is rigged, you shot too fast, my lips hurt because you split them, my ears are aching because you hit them from too close :joy:
And if come you do, my tools borrow you can not :no_mouth:



i get many of the same complaints. came home the other day with all of two marks on me.

on the tool front…happy to share some but not all…usually i do it for them

but still…would be tops to actually meet some of you lunatics with kit that puts mine to shame


Thanks yep, no grub screw.

How do you get them on withought having to hammer the pinion down into the motor rod?

And is there a chance i could have hammered the motor rod further down than expected?

Getting the pinions off so far hasnt been a problem. But i probably need to buy one of those things, brusiemaster also has one.

In to much pain now, but will send photos of motor tomorrow.


it is possible you may have damaged the motor. how likely is another matter.

my pinion gears usually slip on easily enough but i have the D type.

occasionally i get one where i need to grind the center down a bit but its not the norm.

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ok, fk thats what i needed to do - grind it down, i dont even have a grub screw on it, as its so tight it will not move anywhere.

that tool rattler mentioned…that should be your goto

The pinion gear isn’t an interference fit on the motor shaft, that’s the idea behind the grub screw… light tapping to get it onto the shaft maybe, but hammering shouldn’t be required.

I’d be inclined to think the bore on the pinion’s undersize, maybe from the factory. Those motor shaft diameters are pretty consistant.

A good trick for dealing with tight fits is to gently heat up the pinion gear to expand the bore before slipping it onto the motor shaft with long nose pliers. Should just about fall on.