If you can’t fix it with a hammer, you’ve got an electrical problem 
Hey FF that o ring you suggested, do you mean placing it at 1 (before the nozzle tip is glued on) or at 2?
- Between the tip and the nozzle itself.
Though most testing in cyma boxes with that nozzle has usually been borderline too long if using the cyma tpiece.
My testing with it with cyma tpiece has been a gel that might have jammed won’t feed, but seal has been fine.
Thanks mate, I’ll try the original nozzle and tip first followed by the o ring trick second to see what happens.
I’m also now wondering if I glued the barrel in on this one when I replaced it. Will check tonight
Apply moar power. Works for me 
The barrel wasn’t glued in so that got done and retested but unfortunately that wasn’t the magic bullet, FPS was the same glued or not. The friction fit on that was decent.
With that question answered moved onto testing with just the original nozzle, dropped from 300 down to about 285FPS.
Tested with an oring spacer, the LDT nozzle was longer than the OG nozzle so ended up giving me feeding problems (as predicted) 1 in 5 wouldn’t feed or would break up. The ones that did feed well got about 290FPS. A great test anyway that I’ll remember in future, thanks FF
Took a few measurements while I was at it
Landed back at this setup again
80% Cylinder
LDT cylinder head
Polymer piston head
Pink piston
16:1 with two teeth off
275mm 7.5 barrel
T238 29k motor
M110
With the cylinder, cylinder head, piston and nozzle out of the box the airseal testing is excellent, I cant force the cylinder in by hand. Maybe this is as good as it gets
Swapped out the cylinder head today to double check as they’re a slightly different length once seated into the gearbox.
Pulled the tip off the original factory nozzle and glued it onto the new nozzle as it was 0.5mm bigger in diameter but pretty much the same
Plenty of testing, been good fun 
After much faithful service its time for an overhaul.
Not an expert on trigger trolley’s by any stretch of the imagination but the old one was starting to hang up for some reason and the contacts didn’t look too healthy. Also had a squashed magazine wire that needed some love and a cylinder head that was starting to get mangled, the gearbox was in much need of some lube, when it doubt, add lube
Ordered a T238 basic DTU, 40cm hopup barrel, stronger return spring, full cylinder, new cylinder head and some 13:1 gears. Will stick with the 29k brushed motor for now.
Haven’t started a build from a bare gearbox with new gears and an ETU before, so this should be fun
OG trigger trolley setup
Mangled cylinder head, I didn’t choose wisely. An LDT style will be going in next
ETU in, yeah the washer looks weird - I’ve since located the proper screw and washer
Lightening the trigger spring
Some redneck “did I put the magazine terminal wires in the right place” testing
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Awesome stuff! Always love seeing a cyma box getting some love.
Some good tips for the newer T238 installs.
You can put the trigger, sector gear, and selector plate on, close the gearbox up and bang it in the lower.
Connect a motor (preferably a stock shitty one and clamp it down).
Plug in battery. After hearing the beeps, roll the secotr gear and you should see a light flash everytime it is detected. If not, adjust shimming to suit or ETU position.
Move the selector plate and you should hear it beep when it goes between auto and semi. Ideally about half way between semi and auto works best but some boxes/lowers/selectors are finicky.
If it doesn’t beep, trim the rear of the selector plate where the button is. Also be sure to give the selector plate a nice smooth rounded edge so you don’t risk grabbing the wee switch.
And if course, if the selector has the metal sleeve, bin it.
Finally pull the trigger and the motor should go, then stop and whinge when it doesn’t detect the sector gear moving.
Nice to test the function before fully assembled!
Looking forward to seeing how it goes!
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Thanks I’ll start working my way through that check list. One thing though, the entire selector plate is metal, will that give me grief?
That makes removing the metal bit hard!
I normally put a wrap of electrical tape around the arm to insulate it. You shouldn’t need to but safe not sorry theory.
The beauty is rather than trimming the edge you can just put a slight bend in it over the switch to adjust the timing between semi and auto change if needed.