M22 Pressure washer fittings

[46MGTC]

Should I be able to "assume" that all 1/4" M22 threaded high pressure hose fittings would use the same size o-ring? I've got a 7 year Generac One-Wash 3100 psi unit and the hose o-rings are starting to deteriorate. So far I can't locate a specific Generac part number for the ring. I got some generic power washer rings from a friend and with these fitted I can't attach the hose as the ring OD is too large to seat in the female fitting.
Seems a bit odd that there is no standard for these fittings.
Any ideas?

 

[csp]

I wouldn't make that assumption for any product that uses an o-ring.

 

[andyvh1959]

Unless Generac developed some form of custom fitting (not likely), M22 thread is a standard thread size for a number of threaded hydraulic connections. But a "1/4" M22 threaded high pressure hose fitting" is a bit of an incomplete description.

Assuming you mean 1/4" ID hose, with a 22mm thread connection end, is an odd combination. Is it a female swivel nut connection for the hose to the pump or wand? 22mm on 1/4" hose is an odd combination, but not impossible. 22mm threaded connections are more common to 1/2" ID hose, which in metric size is 12mm or 14mm ID hose. The hose end may be a style similar to an ISO 12151-2 spec, which is common to metric hose ends. O-ring material may be nitrile, may be viton, EPDM or silicone. If the washer is for hot water, the o-ring material should EPDM or silicone.

I suggest taking your hose to a local Parker Store, as they'll have a selection of various specification and material o-rings. If you have enough of the original o-ring, they should be able to match the size, section and material. If not a Parker Store, a local hydraulics distributor should be able to help you.

 

[LS6 Tommy]

They are all M22 thread, but the ID of the female part of the inlet connector can be either 14mm or 15mm.

I just went through a smilar thing when I got a new hose for my freebie pressure washer. The inlet for the washer was M22 x 15, most hoses are M22 x 14.

Tommy

 

[46MGTC]

Thanks for the input. I think I know how to proceed.