Two simple questions that came up when mounting tires at home

Two minor questions that came up today when I was showing an inquisitive teen how to mount & balance his own tires for the car he recently got for free from a neighbor.

1. The teen asked me why this slit in the typical air chuck...
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2. The kid asked me what the practical difference was between choosing between two air valves, one for up to 65 psi and the other up to 80 psi for a typical 30 to 40psi nominal economy car tire such as his are:
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In both cases, I told the kid that I don't know the answers and that I'd ask folks on this newsgroup who know more than I do about such things, so I'll point the kid to this thread, when/if reasonable answers ensue.

I did hazard a guess that I suspect the slit in the chuck is perhaps to "let air out", although I'm not sure why we'd want to do that except, I guess, if we use the chuck as the air-release mechanism (similar to the "nib" on the back of a typical pencil-type air pressure gauge).

Likewise, I told him that it doesn't seem to matter all that much which pressure valve we use for his passenger car tires, AFAIK, where I like the brass valve, which happens to handle higher pressure, but I didn't see that it mattered for a passenger car, particularly since they were both essentially the same price.

One happens to be a "bolt in" type while the other is "snap in", but I didn't see that as a practical difference - do you, and one was slightly shorter but only because O'Reillys didn't have the same lengths in stock for the two types.

The specs on the back of the O'Reillys packages are:

XtraSeal 15-4600 Tire Valves 1-1/4" HP 0.453" TR600HP o Max cold inflation pressure is 80 psi o Rim thickness not to exceed 0.205" (5.2mm)

XtraSeal 15-4142 Tire Valves 1-1/2" HP 0.453" TR414 o Max cold inflation pressure is 65 psi o Rim thickness not to exceed 0.156" (3.96mm)

The slot is just like a slot in the head of a screw. It is used for assembly, disassembly

The valve stem is for different rims. Typically truck rims are thicker and heavier and tires have higher pressure.

Hi rbowman,

<slaps head!> That makes a LOT of sense!

o Here's what my old chuck looks like, with the slotted "head" taken apart.

It's only two pieces (3 in total, including the body). o I had never noticed that slot before as I've never needed to take it apart.

Thanks!

Thanks Ed,

Interestingly, there was no steel spring inside when I unscrewed the face.

There was just the screw-off face, the round body, and a "pin" that had a rubber grommet around it (which must act as the "spring").

What the package said was completely clear to me, which was only that it specified only a MAXIMUM thickness and pressure.

I was asking about the unspecified MIMIMUM thickness and pressure, which, I suppose, can only be garnered from experience.

In _my_ experience, admittedly only about 30-odd tires, I've used both types in passenger car tires with nary a leak - but Clare says the brass valve stem "might" leak in a thin rim, even though a minimum spec wasn't specified on the package.

I would have gotten what I normally get, which is 1-1/2 inch brass 0.453" diameter bolt in 60psi valves - but the store didn't have any and this was an emergency mount and balance.

To be clear, the ones I normally get have TWO diameters, because they come with two rubber grommets, one for 0.625" holes and the other grommet for

0.453" holes as shown in this photo from a prior mounting & balance:

Notice, for example, in this photo there are TWO grommets where only one is used, depending on how big the hole is:

Those are the valves I normally use - where in about 30-odd mounts, I haven't had a valve leak yet.

The question wasn't ever about the maximums, since _all_ the valves sold in that store had maximums well above this particular vehicle's spec - so - based on the spec - EVERY valve "fits".

The question was about the minimums, which are unstated on the package.

So many decisions!

See, this is why I take my car to Wally's Service Station and have Goober do my tires.  It's just easier.

The last one I took apart was a Harbor Freight dual head that had a few more pieces. It wasn't curiosity I was trying to get it to work. The solution was buying a real one from NAPA.

The HF compressor is still functioning although I removed the regulator after it blew its guts out. The semi-engaged threads in the pot metal body were not salvageable. The hose and connectors in the accessory pack are functional.

I did find there are at least two styles of 1/4" male connectors. Of course, I bought the wrong style.

Hi rbowman,

Thanks for that additional information, where I assume the "rubber grommet" is the "spring" in this ancient Sears chuck from, oh, it has to be from the

1970's when I first did major body work and painted a car which is why I bought that Sears 220VAC 20-gallan wheeled compressor in the first place.

The chuck doesn't work all that well lately, so I bought this new one to replace it, where when we were replacing the chuck, the kid asked the question, where I _encourage_ all intelligent people to not be afraid of asking questions so that they learn (as do I), from the answers from more knowledgeable people.

Hence I appreciate your experience that you relayed about HF tools.

My experience with HF is similar, in that there are 3 categories (IMHO): o Outright crap that isn't worth a penny (e.g., their 100' air hoses) o Stuff that's crap - but it's worth it (e.g., their tire mounting tools) o Stuff that's ok - so it's a good deal (e.g., tire irons & wheel weights)

Funny you mention the air compressor is still working, as mine is an ancient circa 1970's 220VAC 20 gallon Sears air compressor, which is still going strong (many hoses later).

My biggest problem is _finding_ air hoses that are good but not too expensive. If anyone has a good source for them, let us all know.

I bought the HF yellow plastic coiled hose for short distances, which sucked, as did the black rubber-coated reinforced vinyl 100' hose from HF.

That does drive me nuts that the quick connectors are of different styles, where I only need one, and it's "whatever I've got", which is, I don't remember, but which dates back to the 1970s when I first bought the air compressor.

We once went over the various styles, many years ago, on a.h.r, but I forget offhand what our conclusion was as to the "right" kind to get.

I just want the kind of connector that fits "whatever I've already got" although I _am_ interested in why they have the different types, where all these differences are great, but it still has to fit what I've already got.

I realize that there are criteria that result in different designs but the engineer in me is offended when the main criteria seems to being slightly different from the other company's design. I have a collection of oil filter cap wrenches, all of which are almost, but not quite, the same. Even if the filter itself is for the same applications the different manufacturers have to march to their own drummer.

There are people who like to learn and there are people who don't. o And that's OK.

For example, here's a picture of 3 of my chucks - do you have any advice for how to repair the oldest one, the one at the left, which, I _thought_ was simply missing a rubber grommet - but which seems to be missing a spring (although, I've never taken it apart)?

Only the brand new chuck, in the middle, has an actual spring.

Can you post a picture of the insides of your chucks, so we can compare?

Hi rbowman,

I agree with you that simply having a different size for no good reason than to make it incompatible with others, is a marketing sham.

We should strive to not fall prey to those shams, where, I admit, I must have a dozen different oil filter wrenches myself, from the cap type to the strap type for my non-BMW vehicles (the bimmer has a different kind of oil filter setup).

I just snapped this picture of my disassembled chucks, where you'll note two things of related import. <

>

One is that only the middle (brand new) chuck even _has_ a spring, which may be why I'm unhappy with the oldest chuck from the 1970s's when I bought the compressor to paint my old Japanese sports car.

I have no idea where the spring went, where it's impossible that anyone else has ever had possession of the chuck - so - maybe - perhaps - decades ago - I may have taken it apart and somehow - perhaps - lost the spring?

I can't see the spring leaving on its own.

I could have sworn that I would have had the right sized spring in my box of things, but a look there found everything but the right sized springs. Since I take apart EVERYTHING that breaks, I am surprised I didn't save more of the springs - but alas - I'll have to buy some since I see now that the real problem with the chuck was that I didn't know how to repair it. (And I hate waste - where I feel too many people waste our earth's limited resources by throwing them out instead of fixing them.)

Anyway, the second thing is that the fittings I have on hand are from a batch I bought from HF on sale perhaps a year or two ago, where the red label says that they're "Industrial 1/4 inch Brass NPT M" fittings by a company named "Kobalt" with a SKU of "8 79686 00455 4"

A google search finds this:

I guess that means my fitting "type" is "Industrial", whatever that tells us.

Pretty much, that means I need to _only_ get "Industrial" fittings when I need new ones, where the old ones don't ever wear out - but they seem to hide with the socks.