Propshaft Welch Plug Repair?

[AHM]

Hi All,

I am changing the UJ's on the propshaft and have noticed that the welch plug is missing (wouldn't have crossed my mind if I hadn't read this form).

Does anyone have any tips on fixing it?

Thanks,

Simon

[ardee_selby]

Simon,

It appears that folks on here have had another yoke to use.

It gets a mention of being in Brian Bucklands book, but don't have it to hand and can't recall what it said

However, individual plugs can be obtained e.g.

http://www.ebay.co.uk/itm/Cup-Core-Plug ... 68c7b4a007

http://www.ebay.co.uk/sch/i.html?_from= ... elch+Core+

Or a motor factor in your area? Fitted with a smidgeon of sealant?

Sorry, don't know the size. Anyone?

Good luck - Richard

[alan.barker]

i would suggest that you spot weld the plug in place then put sealant. To be be sure you don't loose the oil from the gearbox.
Alan B

[Sea Ranch]

I'm pretty sure I'm interupting the response to a joke (welding a welch plug . . .) and I'm sorry.

I'd laugh, but for the life of me I can't figure out what a Welch plug is and where it's used!?!?!?!

Randy

[prezoom]

The welch plug is in the end of the yoke, which slips over the splines and into the rear of the transmission. If the plug is missing, gear oil can escape and increase rust resistance of the chassis. Similar to a shoulderless freeze plug.

Rob

[mikealdren]

Sea Ranch,
maybe Welch plug isn't a term used in the US. The plug is a (slightly) domed disc that fits tightly when hammered into a hole of the right size. They are typically used to seal access to water jackets in cylinder blocks. You can apply welch plug sealant to ensure a watertight fit.

In my view, they should never be welded, you would not be able to get them out again or replace them. Plugs in the block do corrode and need replacement, I would certainly replace them as part of an engine rebuild.

Hope this helps
Mike

[ardee_selby]

...but for the life of me I can't figure out what a Welch plug is and where it's used!?!?!?!

Randy

Here's the sort of thing...as fitted to a Holden.

Cheers - Richard

[bcmc33]

The Welch plug is a US invention................

http://en.wikipedia.org/wiki/Welch_plug

[alan.barker]

the question is why was the plug missing . I would say it is because the engine and gearbox assembly have moved back. Maybe in an accident, so the output splined shaft from the gearbox can bottom out . In a cylinderblock i would never ever dream of welding but this is a different situation. The counterbore for the location of the welch plug is likely to be damaged. Two spot welds will make sure that it can not be lost again. For me i hate doing a job a second time and prefer "belt and braces", if you see what i mean
Alan B

[AHM]

Thanks all,

wikipedia (and Mike) - "when struck with a hammer... expands to fit"

I'll try that as the first method, with some sealant for good measure.

Alan, Accident - no. More likely knocked-out in assembly/dissasembly and the counterbore is perfect.

Thanks,

Simon

[billwill]

I've always known those as CORE PLUGs, because they fill up the hole caused by the core of a sand mould, used to cast the metal piece.

[frearther]

Where did the "welch" part of the name come from?

[ardee_selby]

Where did the "welch" part of the name come from?

"The Welch plug was originally designed by the Welch Brothers of the Welch Motor Car Company of Pontiac Michigan in the early 1900s"

Per Brians link to Wikipedia, above.

Richard

[Sea Ranch]

Aren't we just the most inquisitive, informative and interesting bunch of guys anywhere?

Must be the life of the party any/everywhere we go!?

Thanks to you all!

[AHM]

I thought that ?2.74 was a bit steep for a 1" steel disc. And armed with a comprehensive discussion of the origins and design of the Welch plug, all I needed was a 1" steel disc to manufacture said Welch plug. washers have a hole in and making a disc didn't appeal. Then I remembered the Wikipedia article "...drove a quarter or half dollar into the hole."

2p

Job done!

A socket and a small nut provided the necessary press tool to make the dish. Then press to unmake the dish as per answers above.

Thanks,

Simon