Internal Thermostat

[Foster48x]

Hidy ho! We’ll it’s time to get back to work on the old Fiat and I need some advice from the experts. I just found out my 80 FI has an internal 180 deg thermostat in the head and a 190 deg 3-way external thermostat? I thought you either had one or the other?

I’ve read some about people doing internal t-stat conversions on the FI cars. I’m thinking the PO may have tried it since the car was missing the 3-way external thermostat and only had 2 radiator hoses when I bought it. So my question is since I’m planning on keeping my external should I just eliminate the internal? Or should I keep them both?

Rick

[So Cal Mark]

eliminate the internal stat

[Foster48x]

One it is then. Thanks Mark.

Rick

[manoa matt]

Did you discover the 2nd thermostat by chance/accident? Or were you trying to figure out a weird cooling system issue?

Just curious how did the FI engine perform with 2 thermostats?

[Foster48x]

I kind of found it by accident after addressing some overheating issues. I was flushing the system with the external thermostat and all three of the radiator hoses off and noticed that no water was coming out of the radiator tee. I took the tee off and found the stat.

I haven’t gotten everything back together yet but I’m hoping my issues were due to the internal stat trapping air in the head causing the radiator to boil over. I’ll let you know how it runs with only one stat compared to two when I get it back together.

Rick

[vandor]

I’m hoping my issues were due to the internal stat trapping air in the head causing the radiator to boil over.

That would do it... I've seen this before (2 t-stats), plus external ones installed the wrong way around, or totally gutted...
Amazingly, none of that worked

[Fiat88]

I also had found two thermostats installed, one in the head and one external. Just kept the external as advised by the forum.

[GDR76SPIDER]

Hi all. I've searched the forums a bit but haven't found an exact answer. People have mentioned removing the internal t stat. Where exactly is it located in the head?? Is it where the outlet "t" is?

[4uall]

[GDR76SPIDER]

That's one of the pics I saw while searching. Wasn't 100% sure tho. Thanks

[4uall]

Had it not been for my friend (who knows wayyyyyyyy more than i ) I would have never found it. At the time I did not have a replacement gasket so I used a gasket sealent. Good luck

[GDR76SPIDER]

Awesome! Thanks again, I'll be sticking my nose on there tonight and removing it. This forum is amazingly helpful, which explains the low amount of posts I have ( so many questions answered in the archives).