DE UTR-45 power problem after jam

[pyromancer6]

Had a pretty catatrophic BB clog/jam on Sunday's game day with the UTR after it was struggling to feed with the ZCI plastic M4 unit that I put in it alongside a longer 6.03 and a ML macaron, and ever since clearing the jam of around 10+ BBs through the hop-end of the barrel caused by an unlucky shitty BB the power's dropped by almost half, even with the hop completely off and even with changing back to the original hop unit to fix the feeding issue for now - any ideas? (around 1.04J to 0.633-0.673, varies pretty widly - feeding has resumed back to normal since changing back over to the standard intergral nub DE unit though)

Was thinking the jam and the very few amount of rounds through it not knowing it was jammed [as it was struggling to feed, originally just thought it was that before I realised it had clogged] has done something gearbox wise, maybe some sort of damage to the nozzle or other air seal compotents? It seems to cycle perfectly fine still and the falcon-fire hasn't started beeping or getting angry yet so I'm assuming the gears are good still.

Any pointers would be appreciated - I'm really not looking forward to opening the thing up though. Considering that this was my workhorse "it just works" ''backup'' gun I'm a little mad at myself for tinkering with it and seemingly fucking it up, but I guess you can't make an omlette without a few eggs rotting, or something along the lines.

And things were going so well..
 

EDIT:
 

Decided to throw in my desperate attempts to try and fix the feeding problem with the ZCI unit via trial and error here for good measure. If anybody's managed to change their UTR over successfully, please do tell what you've modified to get it to play nice, cheers. I'll take a second stab at it again if I can get this power problem figured out.
 

Hop completely off in all tests , 11.1v 1400 mAH, 0.28g Warhead Delta BBs
 

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Edited April 8 by pyromancer6
added a new section

[Colin Allen]

You are going to have to open it up; it could be the nozzle, it could be the tappet plate, it could be the piston, it could be an airseal.

[Sewdhull]

Yeah you'll need to look inside. Jams can damage stuff way back.

[The_Lord_Poncho]

18 hours ago, pyromancer6 said:

Decided to throw in my desperate attempts to try and fix the feeding problem with the ZCI unit via trial and error here for good measure. If anybody's managed to change their UTR over successfully, please do tell what you've modified to get it to play nice, cheers. I'll take a second stab at it again if I can get this power problem figured out.

 

I've possibly misunderstood what you are asking here - but i have always run a ZCI plastic hop unit, complete with ML Macaron (and i think likely, an omega nub but i can't quite remember)+the original barrel in my UTR 45. Out of the box i was getting weirdly inconsistent power and hop (entirely unusable), so had to switch out the hop  etc . And its been absolutely fine ever since....

[pyromancer6]

On 09/04/2024 at 12:17, The_Lord_Poncho said:

 

I've possibly misunderstood what you are asking here - but i have always run a ZCI plastic hop unit, complete with ML Macaron (and i think likely, an omega nub but i can't quite remember)+the original barrel in my UTR 45. Out of the box i was getting weirdly inconsistent power and hop (entirely unusable), so had to switch out the hop  etc . And its been absolutely fine ever since....

I was getting average (but reliable) performance stock so decided to try the ZCI plastic rotary unit alongside a ML Macaron + gearworks omega nub, and while the performance was much better it just really struggled to feed for whatever reason. I was assuming that other people had modified their units to fit hence the request.

I did change the barrel over to a longer 6.03 (320mm) brass barrel out of a fucked second hand LT-52 I had lying around instead of using the standard 230mm 6.10 that comes as standard when I changed the hop and bucking, however - although since I put the old hop unit back in it's started feeding flawlessly again even with said barrel and rubber (the nub is internally fixed with the standard unit so I couldn't try the gearworks nub in there unfortunately)

 

So yeah, not really sure. Airsoft will be airsoft. If you ever end up taking yours apart for a clean or something similar I'd be interested to see what yours looks like to see if there's anything glaring that I could've missed

Edited April 10 by pyromancer6

[pyromancer6]

Thought I'd reply to this thread with a little update - it ended up being the air seal components as mentioned previously, it was leaking a bunch of air through the cylinder head hence the low power. Replaced the air seal stuff with ak2m4's lovely compression kit and the power jumped all the way up from 0.73J to 1.26J. Used it for most of Friday's game just went with absolutely no problems, ran like a trooper. 

Considering it's the first time I've ever cracked a gearbox, changed things and even attempted my own shimming it didn't end up too bad. Pretty chuffed with it, actually.

 

 

 

 

Edited May 29 by pyromancer6
image link died lol

[MrTea]

Great news that you've identified and fixed your issue and it sounds good too! Is that stock outside of remedial work you've done? Nice work getting it running on the edge of the limit.

[pyromancer6]

2 hours ago, MrTea said:

Great news that you've identified and fixed your issue and it sounds good too! Is that stock outside of remedial work you've done?

It's running a XT High Torque 22TPA that was in there previously (formally a SHS high torque but it died of death because the pistol grip slipped at some point) and the aforementioned compression kit but excluding that it's completely standard on the inside parts wise, just a reshim.
 

2 hours ago, MrTea said:

Nice work getting it running on the edge of the limit.

I might have flubbed the hop amount for the picture when I took it to get it perfect 😅, turns out it was sending 0.28s to outer-space and when adjusted properly at the site it was a little too hot at 1.23~ or around about, so I popped the standard spring back inside which has got it shooting around the 1.01J mark with the hop set correctly - I might look into getting a goldilocks spring that's just right when I order a nice little XT tightbore for it [as the accuracy isn't the best from the random 6.03 barrel I stuffed inside] but I'll cross that bridge when we come to it - I'm just happy to have a pew that works again, especially one that my hands have been on and inside!

Edited May 28 by pyromancer6

[Colin Allen]

19 hours ago, pyromancer6 said:

Thought I'd reply to this thread with a little update - it ended up being the air seal compotents as mentioned previously, it was leaking a bunch of air through the cylinder head hence the low power. Replaced the air seal stuff with ak2m4's lovely compression kit and the power jumped all the way up from 0.73J to 1.26J. Used it for most of Friday's game just went with absolutely no problems, ran like a trooper. 

Considering it's the first time I've ever cracked a gearbox, changed things and even attempted my own shimming it didn't end up too bad. Pretty chuffed with it, actually.


 

 

 

 

 

Well done!  

[JVacation]

@pyromancer6 regarding the hop unit and maple leaf. Barrels have a tiny amount of deviation in dimensions around the window. Some barrels go into the hop unit a tiny bit further than others, not much at all but means that the bottom lip of the maple leaf bucking goes too far into the unit meaning it blocks the feeding tube of the hop unit.

 

To test this assemble the barrel, unit and the bucking as you would and flip it over so the tube which makes contact with your magazine is pointing up. Drop a bb down it and see if it goes all the way into the unit. If it does then it's all good however if it gets stuck halfway use something to test the resistance to push the bb into the unit completely. 

 

If you feel any resistance at all you will need to shave the bottom lip of the bucking a tiny bit just to give more space for it to drop. 

[pyromancer6]

11 hours ago, JVacation said:

@pyromancer6 regarding the hop unit and maple leaf. Barrels have a tiny amount of deviation in dimensions around the window. Some barrels go into the hop unit a tiny bit further than others, not much at all but means that the bottom lip of the maple leaf bucking goes too far into the unit meaning it blocks the feeding tube of the hop unit.

 

To test this assemble the barrel, unit and the bucking as you would and flip it over so the tube which makes contact with your magazine is pointing up. Drop a bb down it and see if it goes all the way into the unit. If it does then it's all good however if it gets stuck halfway use something to test the resistance to push the bb into the unit completely. 

 

If you feel any resistance at all you will need to shave the bottom lip of the bucking a tiny bit just to give more space for it to drop. 

Interesting, I'll give it a little go because I'm sure the plastic ZCI with a dedicated nub's much better than the standard DE hop with an internal one. It was previously mis-feeding every-other shot rather than every single one if that's any indication? Ever since going back to the standard one it's fed flawlessly.

EDIT: 
Had a good fuck around for an hour or two, it feeds a little better on the plastic ZCI unit with a different barrel [CYMA] but it still has feeding inconsistencies - the units are proportioned a little differently from eachother so the next one I get I'll give it a go of filing down to try and match the profile.

Edited May 29 by pyromancer6