Pedcock thread size

[RebuildD1105]

Searching for the thread size for water drain cock hole in a Kubota diesel D1105-E engine. My water pedcock broke off and I need to chase the threads prior to installing a new part. I believe the replacement part is Kubota 15841-73020. I purchased a replacement that came in a bag marked as Onan 185-5490 Cock-Assy. Do you know this thread size or can you direct me to who might?

 

[dlundblad]

Can you take the part to the hardware store?

Should be a tapered pipe thread.

 

[DustyRusty]

Can't say exactly what yours is, but many in the automotive field us 1/8" NPT (National Pipe Thread). I have also seen 1/4-28 machine thread, and checking the O'Reillys website, I see the following sizes listed:
M10-1.25
M12-1.25
M14-1.50
5/8-18 Inch

This leads me to believe that there is no universal size. Back in the 1960's, the common size was 1/8 NPT. If you have to rethread the fitting, then the choice is yours. Just pick the one that you can get a tap easily, and won't be too large.

https://www.oreillyauto.com/shop/b/cooling---heating-16773/radiator-drain-petcock-11358/fc5e9fcf4fd6

 

[North Idaho Wolfman]

It's probably BSPT, it will be the same size as NPT but a different thread taper.

 

[GeoHorn]

Take it to a machine shop if you don***8217;t have a thread-gauge, and they can use a thread gauge to tell you what it is. (Most likely 1/8 NPT. One way to determine is to take it to a hardware store and see if it will thread into a 1/8NPT fitting.)

 

[North Idaho Wolfman]

Take it to a machine shop if you don***8217;t have a thread-gauge, and they can use a thread gauge to tell you what it is. (Most likely 1/8 NPT. One way to determine is to take it to a hardware store and see if it will thread into a 1/8NPT fitting.)

Most likely 1/8 or 1/4 BSPT, Kubota engines almost never come with NPT fittings.

 

[TheOldHokie]

Did you ever find the thread spec? I'm facing the same issue exactly, but I'm in an isolated region and will have to ship in the correct tap.

Measre the OD with calipers. Compare that to the thread charts for NPT and BSPT.

Dan

 

[Henro]

Measre the OD with calipers. Compare that to the thread charts for NPT and BSPT.

Dan

That, and even better, start a new thread rather than continuing one that is almost five years old.

You might get more responses that way…

 

[fried1765]

Searching for the thread size for water drain cock hole in a Kubota diesel D1105-E engine. My water pedcock broke off and I need to chase the threads prior to installing a new part. I believe the replacement part is Kubota 15841-73020. I purchased a replacement that came in a bag marked as Onan 185-5490 Cock-Assy. Do you know this thread size or can you direct me to who might?

What is a "Pedcock" ?

 

[DustyRusty]

That is Canadian for Petcock. Eh???