Boomer 35 HST charge pressure testing

[mklingenmeyer]

I’m trying to fix a 2011 Boomer 35 that’s leaking fluid from the hst.
I want to test the HST charge pressure before I split the tractor. The manual says I need part number

380003163 TOOL​

To screw into the test port. However the tool appears to be unavailable. Can anyone suggest an adapter to test this? Or know the thread size?

I just got a complete service manual for the tractor. Troubleshooting says for hst leak first thing I should test the charge pressure. So I should probably test this before I go ahead and split the tractor.
I doubt this is the problem but it could be. It mostly leaks when running but I think a little comes out when sitting.
Not sure what causes high charge pressure but I guess I’ll figure that out if it tests high.
I posted this in New Holland section but figure this will get more eyes on it. Thanks

 

[dfkrug]

Can anyone suggest an adapter to test this? Or know the thread size?

Looks like it is an extended adapter so that you can access the test port. Take out the test port plug to see what the thread is. If you must use a socket wrench with extension (no access from the side) to get the plug out, weld up your own Special Tool so that you can connect up your gauge.

BTW, before you split the tractor, text all 3 HST pressures (charge, forward and reverse). Sometimes F and R use the same RV. I do not
know Shibaura HSTs.

Extra high pressures can happen when you get contaminants in the RV.

 

[mklingenmeyer]

Thanks. Yeah I have the instructions to test the high pressure forward and reverse also. The port isn’t too deep so I should be able to get something rigged up.
I just need to find a test kit that’s not crazy expensive or gauges and fittings that fit.
They call for 300psi gauge for charge pressure but 100 maybe works. They say 10,000psi gauge for the high pressure.

 

[dfkrug]

No need to buy any special test kit, unless you are starting a career doing heavy equipment mechanic's work. The gauges and adapters are not expensive.

If you don't weld, you can piggyback several adapters to reach as deep as you need to go. The test adapter does not have to be crazy-tight, and it is for only 50-150psi.

Also, your 3 test ports are likely to use the same fitting.