Engine temperature will flux between 190 and 230 back and forth pretty commonly! It never overheats and I have bled the cooling system time and time again! This is a 455 I’m guessing around 1978 model and wondering if it needs a thermostat with a small hole bypass in the thermostat? Any suggestions greatly appreciated!

 

Keep it simple, start by jacking up the passenger front of the car as high as possible overnight, leave the radiator cap off. If there is any air in the system it will naturally work it’s way out. If that doesn’t help, replace the thermostat. Most likely you just have a lazy thermostat that is slow to react to temp changes.

 

It is a Junk Autozone thermostat but only a couple years old! But it has done this ever since that thermostat has been installed! And yes that is how I do it is raising up the passenger side front but have drove it for quite a few miles and it always does this!

 

DING DING DING. We have a winner.

 

AutoZone is great for oils, supplies, things like that. I don’t have much faith in their repair parts, especially if it has the words “DuraLast” on the box. Unfortunately, it seems like all the good name brands most people trusted have either been sold to other companies, or have really let quality control go.

 

It all boils down to money. Companies found they could manufacture cheaper in foreign countries (China) and ship to US for less money. Quality of the product doesn't matter, money does.

 

X2 guys do don't know how many frustrating times on the 64 F-85 build up I have installed "new" parts that fail out of the box or a short time later. Or just as bad they put the wrong part in the box....oh well I'm sure glad I don't do this for a living.

 

It's not just China my British sports cars were a joke! Parts were bad out of the box, rubber stuff would dry rot over a summer and metal parts had to be trimmed before it would fit or seal. Made me want a Japanese sports car.... Tedd

 

The small "bleed" hole is probably a good idea. Put the thermostat and a known good thermometer in a pot of water on your stove and "watch" what it does as you raise the temperature.