Wanted: Fitting Air pump

[Larry Mass]

Hi all I am looking for the fitting that screws into the top of the air pump on my f60. The fitting attaches the steel line to the top of the pump .
Cheers larry

[Larry Mass]

Would any one know the size and thread of the fitting on the top of the air pump on a f60 cab 13.
Larry

[r.morrison]

Hi Larry: I have 2 of those pumps that I think you and I talked about a couple of years ago. I can send you some photos etc. to see if that helps you out. Or you can buy them off me. PM me your email address and we'll see what we can do.
Cheers....Robert

[r.morrison]

Gentlemen: In regards to Larry's dilemma, we both talked and thought we'd give this a shot in the dark. Larry is looking for a special "bolt" that fits into a CMP Air Pump. I have a pump here and am willing to "LOAN" Larry the "bolt" so he could manufacture one. As per the attached photos, it's a bit of work....not like we've all faced this problem. Anyway I thought I would post some photos of said bolt and see if anyone recognises it and is willing to part with it...you know, people like Rob Love and his beloved secret "dump"!

PM me if you can provide any info or contact me through this entry.

Cheers and many thanks....Robert and Larry

[rob love]

Would that not just be a banjo bolt as used on the brake systems of the m35, m37 and m135? There were a couple different threads. If you can measure the threads and let me know what they are, I'll check my banjo bin.

[Grant Bowker]

The cross groove on the end of the banjo opposite the hex looks a little unusual, but if the thread and other diameters and lengths match, surely the banjo could be modified to add the groove.

[rob love]

My thoughts as well Grant.
Now that I think about it, I have a compressor hanging on an old 3 ton out in the back 40. I could have a look in a couple days when it warms up and possibly compare the bolt with the spares that I have.

As an aside, in government supply lingo, the bolts were catalogued as " bolt, fluid passage".

[Larry Mass]

Thanks guys yes the thread looks like a(fluid passage bolt) the challege is to find the right diameter. I tried the bolt from the rear brake cylinder in hopes it would fit but of course it was to small but it did look like the right thread .
Thanks again
Larry

[Mike K]

Hi Larry

Bit of a long shot...

Maybe you could ask around and find someone close by who does hobby machining. Have a look at the Canadian metalwork forums.

https://canadianhobbymetalworkers.com/

That bolt could be made on a lathe. I can do it but I'm on the other side of the planet. Get a ruler or better, callipers and count the number of threads over 1/4 inch, multiply that number by 4 and that gives you the threads per inch (TPI)

These guys are in Saskatchewan https://canadianhobbymetalworkers.co...atchewan.2713/

[kevin powles]

What is the thread diameter?, looks similar to banjo bolts also found on carburettors. If you can tell me the thread size I’m sure they are available here in the uk, just got to file the slot in?

Kevin

[r.morrison]

Gentlemen: Thanks for the input. I've sent the "bolt" off to Larry and he can provide you all the measuements later next week (God willing no postal strike!). Better it comes from one source.

Again, the input is very much appreciated by both parties.

Cheers....Robert

[Larry Mass]

I have just picked up the fitting that Robert sent me I did some measuring the bolt has 18 threads per inch and is 1/2 inch in diameter, hopefully there is some other applications that uses that same size and thread.
Cheers
Larry

[Mike K]

Originally Posted by Larry Mass

I have just picked up the fitting that Robert sent me I did some measuring the bolt has 18 threads per inch and is 1/2 inch in diameter, hopefully there is some other applications that uses that same size and thread.
Cheers
Larry

Hi Larry

That seems to be a oddball BS electrical fitting thread.. or conduit thread.

It doesn't measure up as being: BSF, SAE, UNF, UNC or NPT, BSP..

18 tpi 1/2" is a very unusual size. Measuring threads is a tricky job, I've been caught out a few times , I now use a magnifying glass and callipers. The thread cutting is done on a lathe , you don't need to begin with a bolt with a specific size thread, lathes have the ability to cut many sized threads , both Imperial and metric. This lady explains it https://www.youtube.com/watch?v=q7scadYptTI

[rob love]

I see 1/2-18 taps and die available online including Amazon. The thread is listed as unified extra fine, or unified S, which is a non standard thread which is for specific engineering requirements. I also see that thread listed on some hydraulic fittings, but didn't go too deep down that rabbit hole.

[Larry Mass]

Corection on the diameter ot the blt size it is 9/16 not 1/2 inch but it is 18 threas per inch i used my thread gauge to verify thanks guys, I am still hopeful to find something.
Cheers
Larry

[Mike K]

Originally Posted by Larry Mass

Corection on the diameter ot the blt size it is 9/16 not 1/2 inch but it is 18 threas per inch i used my thread gauge to verify thanks guys, I am still hopeful to find something.
Cheers
Larry

Ah, OK. Being an air line fitting, there is a chance it is a 1/4" NP fitting , which is also 18 TPI but is around .020 smaller than 9/16 “

I do have stored away somewhere, a couple of the CMP Chev tyre pumps, in pieces. Do these have the same fitting ?

Found this pic of the Chev version,it does have a similar bolt.

Edit: had a look and all I can find in my junk is a pump that is missing it's cylinder . So I don't have a banjo bolt that I can use as a sample.

Found this.

https://www.grp4fabrications.com/1-4-npt-banjo-bolt

https://www.proflow.com.au/proflow-f...hnimZQkyqms7WS

[Larry Mass]

That does look like the same bolt the head on the pump looks the same as well, would you have a spare bolt I could buy
Larry

[rob love]

9/16-18 is National Fine thread.
Afraid the banjo bolts I have are either 1/2" or 7/16th.
Thay are made commercially. See here: https://www.fittings.space/gsa29-u09x18m

https://www.jegs.com/i/Fragola-Perfo...50160/10002/-1

[Mike K]

Looking at the pics posted by Rob, it probably is 9/16 UNF but there is a chance it could be something else .

[Hanno Spoelstra]

Larry,

If it is of any help to you, I could take the bolt off my pump and have it replicated here in The Netherlands at my friendly machine shop?