While attempting to install my temp gauge sender in the easy location on the thermostat housing I snapped off one of the bolts holding on the filler neck which had completely seized. A couple drill bits and extractors later the second half of the bolt is still stuck in there.

I don't want to drive the car to a shop since I know it will leak coolant, so how hard is it to remove the thermostat housing? Anybody know a good how-to? Also, will I need a new gasket for the thermostat?

 

Are you referring to the one of two bolts on the top?

If so, just go to a auto store and get a 1mm Helicoil. You'll drill out the rest of the bolt/socket with a 1/4" bit, then recoil it.

Don't ask me how I know about those...

 

Yeah, I had the brilliant idea to remove the filler neck so that I could tighten down the sender without hitting the neck. Didn't work. Ironically I was originally trying to avoid having to drill anything.

Thanks I'll try that. Part of the problem is that I tried to extract it and broke off the extractor in the bolt. So now my bit won't drill into it at all. So I was thinking of trying from the bottom since the bolt goes all the way through.

 

The same thing happened to me. I didn't want to deal with the drilling either, so I just bought a new housing off ebay for $50. I still have my old one with the 2 airpump bolts and 2 thermostat housing bolts broke in it.

 

How hard was it to remove the housing? I'm concerned about breaking other bolts that may also have seized that are more critical/important. Is the airpump bolted to the housing such that if the bolts break they're just stuck in the housing? Are there any bolts going through the housing that could break where the stuck part is in the engine or something worse?

I'll take a look tomorrow night when I have the car, I'm just trying to do some thinking before making everything worse.

 

Well, I started out doing the hose replacement, but wound up replacing a whole lot more because bolts started breaking during the disassembly. I made it a point to use anti-seize compound on EVERY bolt that went into any aluminum part. I really don't want to go through that again.