milKit troubleshooting, tips and tricks


"Valve is not tight"

With a wheel losing air users assume the valve to be the reason most of the time. The reasons for leaking air can be many though: tire/rim, rim/tape and rim/valve or within the valve.
Rim tape installed manually → air escapes under the tape into the rim (possibly at another location than where the valve is installed).
Re-install rim tape.
Valve core not tightened properly.
Apply soapy water on valve and see where bubbles grow (by the valve core or between valve nut and rim).
Air leaking between rim and valve.
  1. Rotate wheel so valve is on bottom.
  2. Rotate wheel sideways (rectangular to rolling direction) so sealant flows along tire wall to the valve.

"I can’t measure the tire pressure"

Depending on the pressure measuring device the knurled nut of the valve core is not pushed all the way down to open the rubber flaps.
  1. Open the curled nut on the valve core fully.
  2. Push the curled nut all the way down.
  3. Is air coming out? → measuring should be fine if your measuring device pushes the nut down all the way.

"I can’t release air from my tire"

Rubber flaps are not pushed open by the valve core extension.
  1. Is the valve core extension installed properly on the valve core?
  2. Was the curled nut on the valve core fully opened?
  3. Try to release air with the applicator needle, then with the valve core again.

"Valve is not tight without valve core installed"

After measuring/refilling when retracting the applicator needle, some air might leak through the rubber flaps.
No worry, this is normal. You still have enough time to install the valve core without losing a lot of air. By pushing the valve core curled knob / valve core extension the rubber flaps can be "re-aligned" so they close better.

"Plunger is ejected from syringe"

Plunger shoots out of syringe when opening the sealant regulator valve.
Open sealant regulator valve slowly and be ready to close it quickly. Plunger moves a lot faster when no sealant is in the tire anymore (only air flow).

Tips and tricks


Leave applicator needle in the valve/tire to refill the syringe.
After the sealant has been pushed into the syringe by the tire pressure you can disconnect the syringe from the (closed) sealant regulator valve.


Lower pressure in syringe before disconnecting it.
Pull the plunger of the syringe out with the sealant regulator valve closed negative pressure in the syringe no drop spilled when disconnecting syringe from the sealant regulator valve.
Wrap paper tissue around applicator needle when retracting from valve.
When retracting the applicator needle from the valve after measuring some drops of sealant might be pushed out of the valve by the tire pressure. Wrap a paper tissue around the applicator needle and valve so no drops are spilled.


Work with sealant if air is leaking between valve and rim.
Don’t tighten the valve nut more than hand tight if there is air leaking between the valve and the rim. Use the sealant to seal the small gap. Rotate wheel sideways (rectangular to rolling direction) so sealant flows along tire wall to the valve.