Freeze plug or ? on my NOV 1929 motor
 

I just recently bought a late 1929 long block from a local old timer. I am building it to put in my 30 coupe due to the existing motor having poorly repair freeze crack...

While cleaning this new motor, I noticed two steel "plugs" which almost look like a ass end of a .45 cal. The plugs are drilled to go into the water jacket. They are located above and between 1 and 2, 3 and 4 cylinders drivers side of the motor. Is this a stock plug to block a hole when machining? Or is this something that someone did later down the road to drain? Or....

Matt

Re: Freeze plug or ? on my NOV 1929 motor
 

Here are some pictures

Re: Freeze plug or ? on my NOV 1929 motor
 

May be "chappets" (I think I have this term correctly spelled) which are steel or cast iron "spacers" which hold the core in place during pouring of cast iron. VERY commonly used on intricate or involved cores to prevent shifting.

Normally these are sort of "absorbed" by the molten iron and you don't really see them on the rough cast surface.

I would certainly pressure test the block you have simply to assure a good starting point for your further work. This test will reveal any flaws. Don't go too high on pressure lest you upset an existing "rust joint" which will henceforth be a leak - at least until the rust joint re-seals (that is if it re-seals.)

Joe K

Re: Freeze plug or ? on my NOV 1929 motor
 

Matt, I think it looks like stitching.

Re: Freeze plug or ? on my NOV 1929 motor
 

I worked for 41yrs in ford foundry in Cleveland and they resemble a chaplet but really don't think so. Chaplets have holes all around the edges for expansion so as not to distort during pouring. I think they are plugs for a small rust through My opinion RAY

Re: Freeze plug or ? on my NOV 1929 motor
 

I've seen them before on rebuilt engines, the rebuilder installs them in the water jacket, if the owner over heats the engine, the center of plug pops out and the rebuilder is no longer responsible for the work he did on that engine.

Re: Freeze plug or ? on my NOV 1929 motor
 

That is the casting wire to hold the molds together when the iron is poured. The excess gets cut off and this is what is left behind. I would recommend getting the block pressure tested as most often the block will leak around the wire.

Re: Freeze plug or ? on my NOV 1929 motor
 

Thank you for the reply. They look like they were in there from day one. I feel you guys are right about them being chaplets. They are equally spaced, and lookin down into the water jacket with the head off I see a raised pc of casting almost like a square. Not drilled through like a stitch repair. Learn something new everyday!

I might sound ignorant here, but is there a way to pressure test the block with it stripped down? I will be taking this down and using some of my b motor parts to make one strong motor.

Re: Freeze plug or ? on my NOV 1929 motor
 

After the rebuild I will be doin a cycle of this through the water jackets/ coolant system.. I bought it for the other motor, but that is too far gone for this to help. I’m sure it won’t hurt!

Re: Freeze plug or ? on my NOV 1929 motor
 

Many of the books show use of a "blanking plate" cut from 3/4" steel plate. Think the head gasket WITHOUT the annular slots connecting the head water jacket to the cylinder water jacket.

One could use a plain steel plate with holes only for the head bolts, but the view of the cylinder bore is obscured at the place where you MOST want to inspect the bore - at the cylinder head juncture. (This is where you'll see valve seat cracks which radiate inwards to the cylinder bore.)

I have made a blanking cover from a couple of layers of 3/4" plywood - this will work but you need a very "squishy" (low durometer) gasket between the wood and the block - the plywood tends to buckle between the bolts under any pressure. I made a head gasket from inner tube.

Between the blanking plate (however you get it) and a hose clamp/plug on the water (lower) jacket inlet you can put a couple or five pounds on it and find most anything you need to know.

I would not use air lest there be some portion of the jacket "ready to go" - and it does - and you get it in the face. ("Gee, it was only 5 psi! - 'Gee, its only 25 stitches...")

Joe K

Re: Freeze plug or ? on my NOV 1929 motor
 

Snyders has a "Block Testing Kit" I have one used it several times. Works great. Just be careful - as Joe K says.

Re: Freeze plug or ? on my NOV 1929 motor
 

Thank you guys I will have to read up on it. Seems like it needs to be done to confirm I’m working with good parts.

Matt