Datsun Roadster Forum-311s.org

Well, the water coming out of the block drain was a little too chunky for my taste, so I pulled the freeze plugs. Wow, I've seen some rust before, but this looked like it was full of corn flakes. Will flush it out ASAP.

The question is does anyone know the size of the freeze plugs on the side of the block? I'm measuring 35 mm, or 1 3/8".

Any input appreciated, including cornflake removal tips. Thought of milk, but then they get all soggy.

Thanks
Dave

and, does anybody know where to find brass freeze plugs? That's what I've always replaced them with in the past, but never in a datsun.

Thanks, Joe

NAPA carries the brass, Now if we can get the size....

The size for the six plugs is 35 mm (p/n 00933-13500 superceded by 00933-1355A)
The single larger rear one is 44.425mm (p/n 11019-32200 superceded by 11019-32201 )
The other plugs are for the oil galleries


Hope this helps.
Ray B.

thanks, that's what I measured, just wanted to confirm

Well the cornflakes and an amazing amount of crusty white crap came out, also the dog was thoroughly entertained watching me spray myself repeatedly with the hose.

I'm glad to get the stuff out, now the radiator can stop being a giant coolant filter!

I saw Dorman also makes a copper bolt in expanding type freeze plug. Might make a great sacrificial anode and slow the aluminum corrosion. anyone remember their galvanic corrosion nobility chart?

Read an article a while back that made alot of sense. He reccomended using only distilled water along with the antifreeze to reduce minerals in the coolant and to get a neutral Ph. Dollar a gallon, why not?

Deionized water is your best source ( Hey Culligan Man ). You only need a gallon each time, so cost it's a concern. The use of a good coolant system flush would be a good idea at this point. But be fore warned of water pump, heater core and radiator leaks that may occur after you get the system cleaned out and properly mixed. Its the natural of the beast, that stuff you refer to as cornflakes, makes good sealant, although bad for your engine! Jersey water, got to love it ! I'm from Philly originally. Expanding freeze plugs, not a good idea ! You want the freeze plugs to go first, then you know there a problem ! Brass, bronze or steel, your choice. Steel seals well, as it expands and contracts similar to cast iron.

My couple of cents,

JC

The water you use can be distilled water. It can't much clearer than that.

The deionized water, I have never seen it on any shelf. Maybe becuase I never looked for it personally. However, I do know where to get oodles of it. In the science lab at the college. It comes out of a endless faucet. The next time you head to campus, just clean out a 2 milk jugs the take it home. I do.

I guess I'm getting older, the next time I go to campus will be to start my daughter in college next September. But in my youth, I do recall removing jugs that were labeled something like "Ethanol".....but I don't remember much after that.