Replacing a freeze plug and valve spring concern

[slomove]

I am having some moderate engine rebuilding done (ZX1/Zetec-E) and I got the head back, looks like new. The engine builder installed new valves because the old ones were heavily pitted and the remaining flange was too thin after grinding. The only thing that worries me is that they insisted that the new valves need no new, higher keeper groove that the previous engine builder put in to avoid coil binding of the stronger Kent valve springs. They are sure it wont bind even with the stock grooves. Well, we will see.

 

Now I am going though some of the removed pieces and found the steel freeze plug in the bottom of the Raceline water rail thermostat housing is almost rusted through. It is about 1.1" diameter.

 

Where can I get a new one and is it easy enough to pound in? I would hate for it to start leaking on a trip far away from home.

[xcarguy]

You might be able to do a match with Dorman:

 

http://www.dormanproducts.com/catalog/hardware2006/127-130_Sec8_Part1.pdf

 

Replacing the plug is no hi-tech event. Pretty straight forward. I've replaced them using hard wooden (oak) dowels, steel bars, sockets, etc. be sure and use sealant. Here's an example:

 

http://m.youtube.com/watch?v=FCAo250tF44

[James A]

I have replaced a number of freeze plugs with no issues, there are several good YouTube videos on this.

[TheDingo8MyBaby]

You may want to give raceline a ring and make sure you get the correct size. You may want to consider brass as it is less sensitive to corrosion and they tend to be a bit softer for easier installation.

[slomove]

You may want to consider brass as it is less sensitive to corrosion and they tend to be a bit softer for easier installation.

 

I was wondering about that. But looking at the table of galvanic potential, I find there is about 200mV between the aluminum rail casting and a steel plug but 500-600mV between aluminum and brass. Or does that matter anyway? Maybe I should try getting an aluminum plug?

 

Or maybe not worry about it because it took anyway 16 years to rust through.....

[coffee break]

I was wondering about that. But looking at the table of galvanic potential, I find there is about 200mV between the aluminum rail casting and a steel plug but 500-600mV between aluminum and brass. Or does that matter anyway? Maybe I should try getting an aluminum plug.

 

Fresh coolant has corrosion inhibitors that should address that issue.

[slomove]

Fresh coolant has corrosion inhibitors that should address that issue.

 

I know but I am not aware that the engine ever had bad coolant. But then, somebody had the car 5 years before I got it and drove it only 600 miles during that time. Who knows what that does.

 

Anyway, I found it a bit confusing to order online and ended up turning my own plug from 1/4" aluminum sheet. That way I could make it fit exactly and hopefully eliminate the corrosion.

[TheDingo8MyBaby]

Didn't realize it was an aluminum rail (guess I should have)?

 

Either way, aluminum should be a good choice. Brass would make your rail the anode.