12a overheat- need advice
 

Ok. I need some help. I was driving my 83 fb home for the holidays. Everything was fine for the first 45 min of the ride. Then, almost simultaneously, my low coolant alarm went and smoke started to come out of the hood. I was not paying attention to my temperature gauge but the engine was obviously very hot. I could tell I had blown one of the gaskets inside the engine because a steady drip of oil/gas/coolant was falling from the engine block. I towed it home and disassembled the engine. I'm afraid the aluminum rotor housing was warped by the heat.

The front rotor housing was the worst of the two. When place on a granite inspection table (which was certified flat), it had a very slight wobble. The difference in rotor housing width was .2mm (out of its .06mm tolerance). There was warpage on both side in the inner coolant jacket (see in pictures).
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The rear rotor was not that bad. It was in the .06mm tolerance and only had the coolant jacket warpage on one side
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So, I just need some advice on what to do now. Is this housing salvageable, or do I need to look for a new engine? My dad works at a metal fab shop and offered to take the warped housing and true it up with a mill (I'm not sure that such a good idea though:scratch:). And that still does not fix the coolant jacket. Just looking for some general advice. Thanks in advance.

I don't think its worth the risk to re use any warped parts. I have a set of 12a housings id be willing to get rid of if you cannot find anything local.

When my last motor blew an apex seal at 213,000 miles, I just bought a junkyard motor for a couple hundred bucks. It has served me well.

The biggest risk with that is that the coolant seals might be bad from sitting. This was the status of my replacement. After installation it started shooting all of the coolant out the exhaust. A $4.00 bottle of Alumaseal took care of that though, and I've been good for 30 some thousand miles.

It's worth considering if you need to go cheap. If you have money to burn, then find a good block to rebuild. Sounds like yours is probably toast, but there are others on here with more experience in rebuilds. I've never done one myself so far. :)


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Thanks for the reply. I don't mind doing a rebuild. I've done one before. I guess I'm on the hunt for a new engine. Do I need to replace the whole engine block or just the rotor housing? And on a different note, how difficult is the 13b swap? I would really like for my fb to be fuel injected.

since the rotor housing is aluminum, you could fix that warped part, but if that melted, what else did?