Schrader valve details

[Tony Smith]

I have been buying replacement Innertubes for 11.00-20 tyres. There are relatively cheap Korean and Indian made innertubes getting around, but they are designed for Dual wheel applications on offset rims and have quite long valve stems. The valve stems are bonded to the tube and can't be easily changed. This is fine if I want to maim passers-by like Ben-Hur's Chariot, or rip the stems out on obstructions. But I don't!

A little more pricier, Michelin make a range of heavy duty truck tubes with replaceable valve stems. The "Standard" stem supplied with the tube is also a long one for Dual wheels (on the left in the pic below), but there are other sized stems available for Single wheel applications like the Blitz (the short one on the right is perfect for both 16" and 20" CMP wheels). Or at least there should be, but demand is low and the Michelin Importer does not have a lot in stock. In fact, it seems I got the last 2. But I do have a few of the stock "Standard" stems which should be able to be cut shorter and rethreaded for the valve.

Which brings me to my question. Does anyone know the thread sizes for the Internal thread for the valve unit, and the External thread for the cap? And the valve seems to seat against a taper within the valve stem at a fairly steep angle, would anyone know this angle, or are there tap and cutter kits available for this job?

[sth65pac]

Tony,

ahhhhhhhhhhhhhhhh Valve, Schrader.

A schrader valve thread is .302-32

http://www.schrader-bridgeport.com/i...Id=5&Itemid=59

http://www.ari.org/std/individual/720-2002.pdf

http://www.schrader-bridgeport.net/b...cation_id=1148

Taps & dies http://www.tapcousa.com

MS288889 Is the Mil Spec

Any other info PM me & I will look into it...

Ian

[Tony Smith]

Originally Posted by sth65pac

A schrader valve thread is .302-32

http://www.schrader-bridgeport.com/i...Id=5&Itemid=59

Any other info PM me & I will look into it...

Ian

Who thunk up that size???? And that first site gives this info:

"Standard valve cores (OEM/aftermarket)
These valve cores all have .206"-36 threads and are compatible with existing U.S.A. and E.T.R.T.O. housing standards."

[Alex Blair (RIP)]

Originally Posted by Tony Smith

Who thunk up that size???? And that first site gives this info:

"Standard valve cores (OEM/aftermarket)
These valve cores all have .206"-36 threads and are compatible with existing U.S.A. and E.T.R.T.O. housing standards."

Tony..
As an old refrigeration mechanic,I have been installing these in all types of applications..
Your tube valve stem is steel and vulcanized into the rubber tube right to the tube surface itself..so ..cut your valve stem down..install an extended tube refrigeration schraeder valve down inside the steel base and then wrap the tire rubber stem in a wet rag or heat displacement gel and silver solder a new extended tube valve into the stem..make it any length you wish..
and it comes with a new cap to boot..
Use the cap to remover the valve before welding and blow out any oxidized surface before reinserting the new valve core..

Schrader Valves

One irrefutable fact about refrigeration systems is that sooner or later, they all need at least one access port. Testing, evacuating, charging - they all require access to the refrigerant circuit. That is where the lowly Schrader valve comes in. If you are changing out the compressor (or any other component) in a small refrigerator, you are going to want to solder a couple of these fellows in place (one on the high pressure side, one on the low).

Note: Use the valve cap (supplied) to remove and replace the valve core during soldering.

Part No. Price Description Qty
Avail.
096-0034 $4.35 Schrader Valve - 1/4" OD stem 47
Quantity:
096-0035 $6.35 Schrader Valve - 3/8" OD stem 4
Quantity:

http://www.rparts.com/Catalog/Major_...oid_valves.asp

[Tony Smith]

Originally Posted by Alex Blair

Tony..

Your tube valve stem is steel and vulcanized into the rubber tube right to the tube surface itself..

Alex, the Michelin truck tubes use BRASS valve stems which come in different lengths and screw onto the innertube. See the pic in my first post. Great system if only the importer would carry the different length stems. I'm hoping to cut the longer stem to length and rethread it for the valve insert.

[Alex Blair (RIP)]

Originally Posted by Tony Smith

Alex, the Michelin truck tubes use BRASS valve stems which come in different lengths and screw onto the innertube. See the pic in my first post. Great system if only the importer would carry the different length stems. I'm hoping to cut the longer stem to length and rethread it for the valve insert.

Tony..
These would be ideal to use with the insert able extended tube refrigeration s valve..
Cut them what ever length you want and use the 3/16ths OD extended tube Ref.schraeder valve,which would slide right inside the original brass valve stem..with low temperature silver solder and Bob's your uncle..
I still have an arm load of them in my tool box and if you fly me over I'll rig you up as many as you want...
I'll be bringing my own snake ..shark..and spider repellent...Comes in 30-'06...

Notice the melting temp on the Easy Flo..
430Deg..farenheit..
I've had sunburns hotter than that..and wimmen...

Stay Brite Low Temperature Silver Solder
This is a versatile non-toxic and low cost silver solder of great
strength for working at low temperatures. It has excellent affinity
for all ferrous and nonferrous alloys. It has more than 5 times the
strength of ordinary tin-lead solders. Can be used for all metals
except aluminum. Stay Brite solder is a composition of 96% tin and
4% silver and will melt at 430°F. The finished joint will be silver in
color.
Kit contains 1/2 oz. of Stay Brite silver solder with 1/16" wire
diameter, 1/2 oz. flux, and applicator

Tensile strength is 70,000PSI and I have soldered joints that have been tested to over 1400psi(nitrogen bottle pressure) so they do hold tire pressure...