240z Thermostat Housing on a 280z
 

I searched and didn't find anything so thought I would mention something I just did if anyone is needing help.

In my 280z, the PO snapped off a bolt in the thermostat housing. He had the top on with RTV and a huge hose clamp. I took it to the machine shop to get it drilled out, and they had to cut off the edge of the threads, weld it up and retap it. When they did this they resurfaced the face and ground out the thermostat groove. While researching I noticed that the 280z housings are super expensive and hard to find, but the 240 housings are cheap and available brand new.

In case anyone is wondering, the 240 will fit the 280 (not a surprise I know), but it also has only two sensor holes. One fits the Temp. Sender and the other will loosely fit the Temp Sensor (an M12 fine thread bolt fit pretty tight in there which I believe is the same thread as the sensor), so I had to RTV grey the threads. It does NOT have a hole for the Thermotime switch. If you have deleted your CSV and EGR group, this housing will work.

There is one caviate however. The Temperature Sensor is too long and will hit the thermostat. There is a way to turn the thermostat so the sensor will only hit the bottom part of the spring. I have yet to test it, but I believe this will not affect the operation. If it does cause the thermostat to fail, I will post it. Hope this was helpful.

Have you thought about a used one? :D They are a-plenty.

I applaud your research though.

You mean from a junkyard? We have an all z junkyard but it's about an hour away through some always ridiculous traffic. Last time I was there it was slim pickins. However if this one starts leaking from the sensor hole I'll probably bite the bullet and drive down there.