82 Owners cold startup?
Burning Brakes
Joined: Mar 2010
Posts: 938
Likes: 15
From: Valdosta Georgia
Well Dub I replaced my 180 deg stat with a 195 and the temp gauge would go up to 210-220 then drop down to 175 and do that over and over. So thinking I had a defective stat I bought another one and that one is doing the same thing as well. Have any idea what's going on? The 180 deg stat did not do that..
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
You probably have a bit of air in the system. Like Dub said if your reservoir and hose are good, it will work itself out. When it cools, check the level in your radiator and top off if needed, also make sure the reservoir is filled to the "Cold" mark (since the engine should be cold when you check the rad) then run it again. When I rebuilt my engine I filled the block through the thermostat mount until it topped off, then filled the radiator and let it sit overnight. When I checked it the level had dropped as the air worked its way out. I also drilled a small hole in the thermostat in case there was any air still in there. I've had no issues since. Once before when we replaced the timing chain and gears we didn't purge the system on refill and I got the same fluctuating temps you are describing. After the engine cooled I topped off the rad and reservoir and that fixed the issue. I'm sure Dub will chime in here as well and correct any mistakes I may have made on the process.
