Thread: Replacing Welsh plugs on truck

While you are at it, look for one in the end of the head. Usually the end you can not get at..........
Put some antifreeze, antirust in it.

Dj, just to make it interesting check a service manual and see if there is a welsh plug in the rear of the block in between the block and where the bellhousing bolts on, quite a mission to replace if it has one there. Anti freeze / coolant usually takes care of the corrosion problem which you have failed to maintain.

Regards Mike

I've cut a hole in the firewall to get at the one in back of the head then just covered the hole with a plate

Have bought anti freeze/coolant to put in, I have only had this truck a short time and that was how it came. Will be getting a good going over soon and all the little bits and pieces sorted out

Interesting to note, these plugs are also called Welch plugs and freeze plugs. and back in the old country some people called them pennies. Apparently a penny was the right size for some of the holes and they were used to replace the old ones.

"Freeze plugs" is a popular misnomer. Frozen coolant will crack the block, not push out the plug. They're actually used to plug the holes left by the lumps of sand holding the sand core in place while casting the engine parts.

Joe

Originally Posted by joe greiner

"Freeze plugs" is a popular misnomer. Frozen coolant will crack the block, not push out the plug. They're actually used to plug the holes left by the lumps of sand holding the sand core in place while casting the engine parts.

Joe

I actually had a Bedford truck in England and didn't have anti freeze in it, just water and a hard frost did exactly that, the plugs pushed out of the block and the block itself was intact, only had to install new plugs. I know this isn't their primary function but have seen this happen on numerous occasions in the uk

Originally Posted by munruben

I actually had a Bedford truck in England and didn't have anti freeze in it, just water and a hard frost did exactly that, the plugs pushed out of the block and the block itself was intact, only had to install new plugs. I know this isn't their primary function but have seen this happen on numerous occasions in the uk

Happens often enough to justify the terminology, I guess. Probably a threshhold where the remaining frozen coolant would still crack the block; maybe in the far north, such as Scandinavia, Alaska and such. Nice to know they sometimes work that way, though. Thanks, John.

Joe

A motor mechanic friend of mine gave this tip on installing welsh plugs. Use a socket that fits tight in the plug [ I had to grind a socket to fit my plugs tight] and you can control the angle of entry easily. You can add an extension piece to the socket if it is hard to hit.
les

Originally Posted by echnidna

I've cut a hole in the firewall to get at the one in back of the head then just covered the hole with a plate

You too huh?

Mick

No flies on us Mick

Originally Posted by echnidna

No flies on us Mick

No, but you can see where they have been.

don't forget the "stag".

krikey that stuff has been arround a long time & is still remarkable stuff.

its food safe too.

cheers

Originally Posted by joe greiner

"Freeze plugs" is a popular misnomer. Frozen coolant will crack the block, not push out the plug. They're actually used to plug the holes left by the lumps of sand holding the sand core in place while casting the engine parts.

Joe

Hence the Australian common name "Core Plug"