[FaceFaceMan]

1991 Lude B21A1 (damn bastard) Si ALB <--(being deleted)
138K miles

Half way through my auto to manual swap. I'm now addressing the motor. Timing belt, water pump, gaskets etc.
I noticed when I pulled the motor for the swap, I found what I learned was the cap for the block heater plug laying in a cavity around the plastic intake resonator above the steering rack sub frame.
At some point, someone made this repair. (Many years ago)
It looks like a rubber expansion plug for testing plumbing. I drove this car for a few months to shake it down and fix most of the common issues before deciding to do the swap. (only 4 gears in auto?! At highway speed!? Like Jem and the Holograms, truly truly truly outrageous.)
It never dripped a drop of coolant. Only once I got it bolted to my engine stand, sure enough I see pic related.

And here's a closer image of the plug I took tonight. (the first pic was weeks ago before I wiped the drip and took a wire brush to "dust off" my water pipe)

My question here is, has anyone used this style replacement? (Yes, I did a search in the forum and read through several arguments about what a freeze plug is vs an expansion plug from casting blah blah)

Funny thing is, I found a site that listed the exact OEM plug minus the bolts and when I ordered it they emailed the next day to tell me they forgot to update their site and it was of course discontinued. Par the course right?

My gut tells me to try and use a similar style rubber plug. Is this some home made janky fix? I'm not against it but I know once I try and loosen that bolt, even with a treatment of "knock-er-loose", I'm at the point of no return.

Just curious if anyone here has come across this particular issue.

 

[1funryd]

Nope, its not a common issue since most of us do not deal with super cold temps.

 

[luzer]

Pretty sure I have one or two stock plugs in my parts bins if you're interested in one. Of course it would need a new o-ring.

 

[FaceFaceMan]

Nope, its not a common issue since most of us do not deal with super cold temps.

That makes sense. Just curious in general if anyone had seen this application of a replacement plug used, even in other platforms. I lucked out with my Lude. It originated in NY but made it's way down south maybe around 20 years ago? Aside from some fender well rust I'll attack later, she's very much intact. There's fluid film underneath and made pulling the heat shield for the exhaust underneath a blessing. We don't see those low temps down here in the south east either. I worked flat rate many years ago and had snow bird cars coming from Florida back up north for repairs. You touch a part and it crumbles into dust. Hopefully they get paid very well up north with all the salt damage. I'm thankful I can turn wrenches for fun now rather than having to pay bills.

 

[FaceFaceMan]

Pretty sure I have one or two stock plugs in my parts bins if you're interested in one. Of course it would need a new o-ring.

I appreciate the offer. After more research today I decided I think I might have a solution. I found some cheap expansion plugs (or test plugs in the plumbing world) as well a pack of freeze plug replacements that might work online. I'm confident one of the two should work according to what I've read. The temporary ones have survived for years in some engine blocks. I'll know soon enough and perhaps make a new thread if it works. I've been documenting the whole process so I might make a video too. Thanks for the reply. I might be interested in them just to have an oem solution down the road. Or you might wanna ebay them yourself. As everyone knows, these parts are very few and far between. Just look up what people are charging for a flywheel bolt for a 3rd gen! Something something supply demand. I'm labeling and boxing up everything I'm deleting and storing it.

 

[FaceFaceMan]

I'm responding in order to make sure this thread has closure. My solution worked. I purchased this 34-38mm neoprene expansion plug. I hope this helps someone in the future.

My Lude started up north, but made it's way down the east coast many years ago well after whatever cold weather it experienced. I thought NY because of a radio sticker I haven't peeled off the back bumper but discovered the original dealership billfold from New Jersey in the glove box. Along with service records for the past decade since it's been in NC.

This medallion of what I believe to be Saint Maria was in it. Could anyone translate it for me? It will of course stay in the Lude for blessings.

Thanks again to this forum.