4AD engine Freeze Plugs

[ucantucan]

I can't seem to find the proper size freeze plugs for my engine. It looks like I need aprox 1.171 inch ( 29.75mm) plugs. Does anyone have a source for these or alternate ideas, short of re-spot facing the case?

Thanks

Greg

[mikeyr]

Standard plugs worked fine. I put them on a 1" socket upside down and smacked them in the middle to make them the right size. Basically I could not get the right size either and I got brass ones, put them and made them fit, pretty easy and still no leaks after 20+ years. You just make them more concave or convex depending on how look at them and it will shrink them the tiny little bit that is required, standard ones are just a tiny bit too big. You HAVE to do with brass, if you get steel ones you will have to fight with them to shrink them, like heat with a torch and then smack them...much easier with brass.

[BRG]

The number is Dorman 565-021 for brass. One thing with shrinking. I use a small ball peen hammers round end against the plug and strike the flat end of the small ball peen with a bigger ball peen hammer. This lessens the chance of striking off center and damaging the freeze plug.
BRG

[Mark Thompson]

The Dorman 565-021 is no longer available. Does anyone have a recommendation for a 4AD head freeze plug?

Mark Thompson

[Stephen]

Hi Mark,.. I had the same problem last year when rebuilding my 4AD motor, and the welsh plug or freeze plug as you call them, in the correct size is almost, or impossible to find.
You may find some new old stock at a swap meet, but I gave up after attending numerous large swaps and finding nothing.
I ended up finding some plugs that were, just a little oversize, and ground them down.
If you have a grinder, hold the plug between your thumb and forefinger, loosely and put the edges to the grinder, the force of the spinning grinding wheel will rotate the plug. The tighter you hold it the less round it will turn out, with some trial and error, you will be able to get the plug to just the right size to fit the opening.
I then put some "Stag" (which is like red oxide gasket goo), on the edges of the plug, used a socket on a short bar, gave them a whack and they expanded out to a nice tight fit.
Hope this helps.
Stephen

[Mark Thompson]

Thanks Stephen,
Do you have any specifics about the plugs you adapted? Size? Brass or Steel? Concave or Plug? Brand? Model No.? Website? Store?
Best Regards,
Mark

[Stephen]

Hi Mark .. I am not going to be much help to you unfortunately ..
But I just measured an old block I have here and the size comes up at 29.32 mm or 1 5/32 "
You can only use the dome type plugs. as the recess for them in the block is very narrow, and the standard deep side plugs of today with the straight sides will not fit, sides are two long, and even machined down the radius on the edge prevents the plug from fitting correctly.
I bought mine from a swap meet, ( not much help am I ) I do not know where you can get the dome freeze ( welsh) plugs in the US., and the size I ground down were 32 mm as that was all I could get at the time I needed them.
Because they were hard to find, (and I am sure I will need some more in the future) I buy all I can find now at swap meets, and have a small collection of various sizes.
If you get stuck, let me know and I will post a few over to you to play around with, I measured a few that I have and some are very, very close to the size required.
If you want some PM me with your postage detail..
Regards
Stephen

[Stephen]

PS.. I used brass and steel, as beggars cannot be choosy