Replace block drain with bolt? (1 Viewer)

[Oregon LC]

I removed an old block heater from the PO that was plumbed directly to the engine block via a steel nipple. Worked good never saw any leaks.

Now that the steel nipple is gone I need to find something to properly plug the hole. The hole I'm referring to is on the driver's side where the factory block drain once was. The attached pic is the block drain from my 77 which still remains original.

Can I just use a brass or steel bolt to plug the hole? Or will it possibly restrict the flow of coolant for other areas of the block? I'm not sure if this is a water jacket or just a drain in the bottom of the block?

Thanks

 

[Steamer]

You didn't mention if your missing one or both parts of the two piece block drain. ToyotaMatt has the complete drain valve. "LINK" (Post # 3) The threads in the block are 3/8" BSPT (British Standard Pipe Threads) You can make a starndard easy to find 3/8" NPT pipe plug work but it's not right. The thread count is one thread off. If you do that, make sure it's brass so you'll distort the plug threads and not the block threads. Better off to just get the right valve.

 

[Oregon LC]

You didn't mention if your missing one or both parts of the two piece block drain. ToyotaMatt has the complete drain valve.

@Steamer Yes I am missing both fittings. And thanks for the information about the thread pitch.

 

[Dizzy]

You didn't mention if your missing one or both parts of the two piece block drain. ToyotaMatt has the complete drain valve. "LINK" (Post # 3) The threads in the block are 3/8" BSPT (British Standard Pipe Threads) You can make a starndard easy to find 3/8" NPT pipe plug work but it's not right. The thread count is one thread off. If you do that, make sure it's brass so you'll distort the plug threads and not the block threads. Better off to just get the right valve.

Are all of the original fittings BSPT? I'm thinking about the intake manifold, the sensor(s) on the head, the thermostat vacuum meter, the fuel pump, etc.

 

[GA Architect]

Click here for the missing part: 96431-03833 (supersedes to 96431-53828)

 

[Steamer]

Are all of the original fittings BSPT? I'm thinking about the intake manifold, the sensor(s) on the head, the thermostat vacuum meter, the fuel pump, etc.

All that I have checked are BSPT and I believe that all the pipe thread fittings are BSPT. All BSPT thread pitches are different than NPT except for 1/2". They share the same pitch (thread count) but the taper is slightly different. Also the angle of the threads are slightly different. Using 1/2" NPT in place of 1/2" BSPT works fairly well. But getting the proper BSPT is best.