I recently completed installed a new head gasket, had the valves redone and got the head decked, added a weber carb, and desmogged my 22r. It has been running great, but I have only done a few short drives with it. I took it out today and after about 15-20 minutes of running, my temp started getting high. I didn't want to wreck my new head gasket, so I shut her down well before reaching the red line on the temp gauge. I had to make a couple of cool down stops to get her home. It started making some valve noise too, once it got good and hot.

During the head gasket job, I replaced timing chain guides, water pump, and thermostat. So I am a little baffled by the heat issue. I thought it could be running to lean, so on the way back I actually gave the mixture screw on the weber (which I had adjusted according to the factory instructions) about a half turn more rich. I am beginning to suspect that I may have gotten a bad thermostat, as it seemed really good on the shorter 5-10 minute drives. Does anyone have any ideas about this issue?

The valve noise is probably a separate issue, but I did adjust them to spec cold after installing the head. I also idled it for about 10 minutes after the head was installed and re checked the valves hot... Perhaps I should get it hotter and then recheck the valve clearance?

Thanks for the input. This has me a little frustrated.