Any idea where these (I think) engine plugs go?

[Michael L.]

Guys,

Please take a look at the attached pics of presumed engine plugs and enlighten me as to where they go. I think the larger one goes in the drivers side cylinder head (as pictured) but no idea about the others. Not even sure if they're engine plugs. Thanks.

Mike

[Jimmy P.]

Re: Any idea where these (I think) engine plugs go?

Guys,

Please take a look at the attached pics of presumed engine plugs and enlighten me as to where they go. I think the larger one goes in the drivers side cylinder head (as pictured) but no idea about the others. Not even sure if they're engine plugs. Thanks.

Mike

Not real sure, but the smaller ones look like they could be used to plug the manifold after the smog tubes are removed! That would be my guess for those four. Can't really tell the size from the picture.
Regards,

[Jim D.]

Re: Any idea where these (I think) engine plugs go?

Could be oil galley plugs in the back of the block or possibly coolant drain plugs on each side of the block.

[Michael L.]

Re: Any idea where these (I think) engine plugs go?

OK. Don't think they are from the smog tube holes, as the smog pump and tubes were in place when the engine was disassembled, although that was one consideration I had. I guess could be oil galley plugs but I'm guessing my engine shop just replaced them with new if they weren't in there when they went to assemble it. Manifold is on already so no way to check unless I take it off which I prefer not doing. I'll check the side coolant drain plugs again but don't think they seemed to fit anywhere there that I could see.

You think I have that larger plug in the correct location?

Mike

[Patrick H.]

Re: Any idea where these (I think) engine plugs go?

They sure look like coolant plugs to me. Usually these live at the very lower edge of the block, 1 per side.

I replace them with brass, as they love to rust in place.

[Joe L.]

Re: Any idea where these (I think) engine plugs go?

Mike------

The large internal hex head plug looks like the one used on the cylinder head as you have shown. However, it's NOT used on the left, forward position as you appear to have shown. That position is used for the engine temperature sender for 1969. The plug is used at the right, rear position. From what I can see of it, the internal hex appears to be somewhat damaged. If so, replace it.

The smaller plugs appear to be the coolant drain plugs used on either side of the block. The corrosion damage on the inner end further supports this. However, there are only 2 of these per engine so I don't know why you have 4. Except for the coolant drain plugs, I know of no other application for this size and configuration plug on a small block engine. I agree with Patrick. Use only brass plugs of the same configuration for the block coolant drain plugs.

By the way, on another subject, the valve spring caps (retainers) on your valve springs do not appear to be stock-type from what I can see of them. Also, if you are using stock-type o-ring valve stem seals, then you MUST also use the stock-type metal oil shields under the caps.