Tools required to repair V812 Vacuum:


screw driver, wrenches, plyers, Q-tips, rubbing alcohol, paper clip, Teflon tape, pen, V812

V812 Vacuum Repair

Check first to see if you have a problem with the V812:

Air escaping from the case is normal if you are generating vacuum.  Escaping compressed air across the high performance venturi generates the vacuum.

Check air in pressure is set to 85 PSI or more. Put finger over white fitting and turn on system. Check vacuum gauge. Maximum achievable vacuum is dependent on altitude and barometric pressure. (low pressure = lower achievable vacuum) Normal at Sea level is 20"-25"+ hg.


Problems that can occur:

The V812 Vacuum Generator performance can degrade or completely stop if clogged by debris from a dirty compressor, excessive water in the compressor, or excessive dust is pulled into the system.


If there is excessive water in the compressor, drain per your compressor manual. Turn vacuum generator back on to dry out Venturi. If water continues to be a problem, a water separator is recommended.


If this is not the problem it is most likely that some debris is clogging the venturi.


The following shows you how to completely disassemble, clean, and reassemble the V812.

Steps to Repair V812 Vacuum


Step 1: Remove end caps with screw driver or thin tool.

Step 2:

2a: Remove Air-In brass fitting

2b: Check screen inside Air-In brass fitting for debris – clean if required.

Step 3:

3a: Remove vacuum filter (white fitting). Caution: Use wrench carefully on flats or more damage could result.

3b: Check screen inside filter for debris – clean or replace if required.

Caution: Screen inside filter is very fine and delicate.

Step 4: Remove valve handle

Step 5: Remove Vacuum Gauge. Use a 7/16” end wrench if required. Often twisting by hand will be all that is required

Step 6: Pull assembly out of the case. Note position of valve lever limiter (aluminum part on valve – will fall off).

Step 7:

7a: Remove blue hose from black fitting. This fitting is a press in fitting and the collar needs to be depressed. Note: In image, the pen is pointing to the collar that needs to be depressed to release the hose.

7b: Depressing both sides of the collar while pulling hose out of fitting.

7c: Hose removed. Collar shown is still depressed

Step 8: Disassemble On/Off Valve from vacuum venturi.  Use wrenches on flats.

Step 9: Shown completely disassembled


Step 10:

10a: Remove Knurled Cap from body, using wrench on flats and pliers if needed. Hand unthread maybe all that is required.  Note: there is a retaining washer that may or may not have vent holes and white muffler that may fall out.



10b: Remove White Muffler from Knurled Cap, push out with paper clip if required. Clean if required

10c: Venturi with muffler and retaining washer removed

Step 11: Remove center post. Pull straight out by hand

Step 12: Push out insert from threaded side with a paper clip.

Note: be ready for a very small part to pop out of the other end

Step 13: Venturi is now completely disassembled and ready for cleaning.

(shown with solid style retaining washer)

Step 14: Clean with isopropyl alcohol, swabs, rags, and compressed air


Step 15

15a: Insert small part (light silicone grease on O-ring if required)

15b: Using a slim line pen with pen retracted will help center and seat small part into hole

Step 16

16a: insert post into body (light silicone grease on O-ring if required)

16b: Press to fully seat

17: Install retaining ring over post (either as shown or solid ring)

18: Install White muffler into knurled knob – open hole facing out

19: Screw knurled knob onto body – hand tighten. Possibly will need a wrench on the flats to hold body from turning while tightening knurled knob.

Note: black portion is designed to rotate allowing easy positioning when installing into case.

20a: Reattach Vacuum Venturi to On/Off Valve Body (If Teflon tape is used – keep tape below the first few threads to keep the tape from shredding and clogging the Venturi).

20b: After tightening align the black hose fitting opposite from fitting on other side of valve. This can be done by just rotating the black portion of the Venturi which will rotate around.

21a: Insert blue hose into Venturi fitting

21b: Press hose to completely seat into press lock fitting

22: Assembled. Check to make sure other hose connections are secure

23: Reinstall Aluminum valve limiter into place and slip assembly into case

24: Reinstall Air-In Fitting and ONLY hand tighten at this point

25: Reinstall Vacuum Filter and ONLY hand tighten

26a: Apply Teflon tape or liquid thread sealer to Vacuum Gauge threads

26b: Leave the first few threads clear to keep tape from shredding and clogging venturi

26c: Reinstall Vacuum Gauge – HAND TIGHTEN ONLY.

Stop when aligned to read before bottoming out.

If Gauge does not align to read and has bottomed out – LOOSEN the gauge.

DO NOT OVER TIGHTEN. The Teflon tape will keep from leaking and does not need to be tight.

If desired a spacer/washer can be added over the Gauge threads to allow the gauge to bottom out at a higher height and be tight.  Still Hand Tighten Only.

27: Reinstall Valve Knob

28: Reinstall end caps – press into case

29: Tighten Air-In fitting with Wrench

30: Tighten Vacuum Filter – ONLY SNUG DO NOT OVER TIGHTEN

31: That is it!  FINISHED – with the tools you used


Connect clean compressed air at 85psi or more to Air-In

Put finger over white Vacuum Filter opening

Rotate Valve to full ON

Check Vacuum typical at Sea Level 20"-25"+hg


NOTE: Air escaping from the case is normal from inside the case. The internal Venturi uses compressed air to create vacuum.




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