HST Pressure Tests. B7200 HST

[cb750k8]

Hi
I intend to carry out pressure tests on the HST(Hydrostatic Transmission) of my tractor generally as per the service manual but with home made hoses. I am sourcing gauges at present. The HST is fine, some noise but I understand that is normal. I am not familiar with HST's.

I have some queries.

1) Has anyone carried out these tests?
2) Anyone know threaded connections are BSP, NPT, Parallel or what and what sizes
3) Is access to the connections (5 off) reasonably easy ie without a major tear down?

.PDF from service manual attached
Thanks in advance.

 

[Stubbyie]

I '''think''' you're going to find all the 'pipe' threads are British Standard.

Caution is in order because if you're almost-but-not-really-correct the pressure may easily blow out your adapter and strip the female threads. And lose fluid and perhaps damage you.

Most if not all these threads are similar enough they can be mis-identified if not careful.

Does the Workshop Manual list items needed to conduct these pressure tests and their respective threads?

Please post back your experiences so we may all learn.

 

[North Idaho Wolfman]

Stubbyie, I thought the same thing about the treads, they should be BSP, But my L3450 has 1/8 NPT fittings on the test ports for the GST.
So check them twice, and don't force a fitting into place.
I just got a couple simple pipe plugs to test first before I committed to buying the "right" fittings.

 

[cb750k8]

All
Thanks for the responses.
HST test equipment, extracted from manual, attached.
A "bag" of hydraulic hose and fittings is on its way to me. I will sort through this and whatever is not available I can obtain in the local hydraulic hose shop. They can also do crimping etc.
It may be some weeks before I can complete these tests but I will keep all informed of results.
Cheers

 

[Stubbyie]

Refer to the PDF posted previously in this string and note the different threaded adapters. I had not noticed this previously but a similar page is in my WSM.

Apparently Kubotas may be found with different threaded ports--whether just for the hydrostatic system or otherwise on the tractor I don't know.

Caution with those adapters, as the link below points out what may be subtle differences.

LINK:
http://www.engineeringtoolbox.com/thread-standards-d_776.html

Please post back your continuing experiences so we may all learn.