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Topic: 1991 GV U300 What air fitting do I need (Read 341 times) previous topic - next topic

1991 GV U300 What air fitting do I need

I was trying to refresh my air system
Rebuild 1991 GV GAST 5HCD-10-M500X Onboard air compressor

When wet tank drain is open, both front and rear tank pressure drops. So first step is to replace check valves.  Bought 4 Bendix 227871 SC 1 check valve from ebay at $11 each free shipping.



It was not an easy job to take off the old fittings. Certainly the check valve is beyond rescue. There is so much rust.


When I took the check valve with the Tee fitting, it was seized so bad that I broke one of the fittings. As you can see from the above picture, it seems like check valves=> reducer => Tee fitting. The reducer was broken.

The tube connected to the Tee has SAE J844 Type B 1/2 so I assume the T is 1/2 compression fitting. Nut I am not sure the thread to the reducer.

What reducer can I buy to connect from the check valve and the tee?
Is there any Tee that can connect to the check valve without the reducer?
Thanks




Re: 1991 GV U300 What air fitting do I need

Reply #1 –
When I replaced the check valves on my tanks, they also had reducer bushings between the compression fittings and the check valve.  I believe the thread on the check valve is 1/2" NPT (male and female) on both ends.  The compression fitting thread going to the reducer is probably either 1/4" or 3/8" NPT - I don't remember which.  Either way, the reducer bushing should be easy to find at Home Depot or Lowes in the brass fittings dept.  Take the check valve and the "T" with you to the store to get the correct part.

Part Number Collection  (Reply #89)

Re: 1991 GV U300 What air fitting do I need

Reply #2 –
If you wanted to get rid of the reducer bushing, they do make 1/2" tube x 1/2" tube x 1/2" NPT "T" fittings.

New-Line Hose & Fittings

 

Re: 1991 GV U300 What air fitting do I need

Reply #3 –
Quote from: Chuck & Jeannie –
When I replaced the check valves on my tanks, they also had reducer bushings between the compression fittings and the check valve.  I believe the thread on the check valve is 1/2" NPT (male and female) on both ends.  The compression fitting thread going to the reducer is probably either 1/4" or 3/8" NPT - I don't remember which.  Either way, the reducer bushing should be easy to find at Home Depot or Lowes in the brass fittings dept.  Take the check valve and the "T" with you to the store to get the correct part.

Part Number Collection  (Reply #89)



Thanks!

By looking at the pictures, I think the parts are different for 93 and 91. I think I needs a 1/2 npt 1/2 compression fittings tee.
To save time, I am going to buy many fittings and find one then return others.