ump motor

peter-pantslez

hey my ump has started making funny clicking sounds.

before this happened its rate of fire went right down and then back up again a couple of times.

is this the motor and if so will any replacment motor work in it?

Masada

you need a short type, typical V3 motor will work in it, aswell as M14 motors etc.,

peter-pantslez

cheers vtec!

kdouglas

might not be the motor though, have you tried any other batteries in it?

peter-pantslez

kdouglas wrote: »

might not be the motor though, have you tried any other batteries in it?

havnt had a chance to yet but i will later

peter-pantslez

ok took your advice KD and tried a new battery and it didnt work.

so i stripped her down and tried the motor on it own and it worked. that ruled out a motor problem.

so opened the gear box up and one of the gears is missing half of it teeth:(


iv recently had this gear box open to change an air nozzle, would it have been something i done wrong when reassembling that done this or what would have caused this?

and also would i be better off changing all the gears now or just the broke one?

iv inspected the others and they are all fine bar this one.

Masada

depends on if theres any obvious damage on the others, id say by looking at how badly you ripped that one up theres a good chance the others will have some probs,
you might have messed up on the shims and left the gears fitting awkwardly and that would happen as a result.

Ya might aswell get some decent bushings in too now that its all taken apart,.

peter-pantslez

sure i may aswell change the lot so!

will the 7mm bushings tony sells fit? and the same with the gears?

or where will i be bale to pick them up??

Masada

yeah 7mm bearing bushings is what ya want, the gears are just the regular v2/v3 gears so no probs getting them, dont forget shims though, their probably more inportant than the bushings.,

peter-pantslez

stupid question vtec but what exactly are the shims???

Witcher

peter-pantslez wrote: »

stupid question vtec but what exactly are the shims???

They are like really thin discs that go between the gears to space them out

Masada

yup. as blay said, their just spacers to make sure the gears are engaged properly and dont have any rattling in them.,

Head_Hunter

Are you sure the gear that is apparently missing teeth isn't the sector gear? The sector gear doesn't have a full set of teeth.

peter-pantslez

Head_Hunter wrote: »

Are you sure the gear that is apparently missing teeth isn't the sector gear? The sector gear doesn't have a full set of teeth.

positive because the missing teeth off of the gear were inside the gear box when i opened it up!

peter-pantslez

vtec wrote: »

yup. as blay said, their just spacers to make sure the gears are engaged properly and dont have any rattling in them.,

and is it just one goes each side on the gear or is there more to it than that?

Witcher

peter-pantslez wrote: »

and is it just one goes each side on the gear or is there more to it than that?

Make sure there are just shims enough to make the gears grip each other

well, and that they dont rattle as vtec said, but dont put too many in as it

will restrict the gears from turning,, its a fiddly job

peter-pantslez

Blay wrote: »

Make sure there are just shims enough to make the gears grip each other

well, and that they dont rattle as vtec said, but dont put too many in as it

will restrict the gears from turning,, its a fiddly job

it sounds fiddly alright cause you cant exactly see in to the gear box to tell if there close enough!

if i just using the same ones off the old gears on the new ones will it work?

Puding

if i just using the same ones off the old gears on the new ones will it work?

it can be a good starting point but you will have to check yourself thought, the new gears will have different tolerances, i normal take everything else out of the gearbox that will come out out and just put the gears into the box after that, a lot easier to shim if there is the minimum amount of parts in there at the start, once your happy that everything is lined up right, take note of the shims used and on what gears and you can replace all the other parts (reshiming with a spring in your mechbox is not the best thing )

peter-pantslez

thanks puding il give it a go whe i get the parts!

Witcher

peter-pantslez wrote: »

it sounds fiddly alright cause you cant exactly see in to the gear box to tell if there close enough!

if i just using the same ones off the old gears on the new ones will it work?

It should do yeah, but the gearbox may not have been shimmed right as

stock so you may have less shims than ya may need for the new gears, trial

and error tbh, shim it with your existing shims and se if they engage right and

if need be buy some more to tighten it up