I bought an Edelbrock 8604 thermostat (180 degrees for small block Chevy) - when I boiled it on my stove, using a digital thermometer, it didn't begin to open until around 187 and fully open at around 195. I figured, okay screw the high performance high flow Edelbrock nonsense and see how an AutoZone unit performed. Went and got a Failsafe brand 180° thermostat and boiled it. Began to open at 186 and didn't fully open until around 200. What's the deal here? Anyone have a suggestion on a reliable, proper functioning thermostat?
I was never worried about the actual temperature, just Verified it opens before the water is boiling. Edit: at what temp did it fully close at?
Stant has always been good for me. I have not bought any recently because the ones I have are still going strong. I do know that they were bought out and folded into the MotoRad company so I’m not sure if the quality suffered. I have bought a few for my old tractor recently and they were way off as far as opening temp. They were an off brand name from a tractor supply house.
I never did a temp test but a friend suggested I use one in a lower range than the OEM specs call for. He learned that from another guy. We have the same, and more modern, engines and mine runs 205 - 210 on hot days just fine.
IF they're actually opening at a higher-than-designed temperature, AND IF a lower temperature thermostat opens at a higher-than-designed temperature, then get a lower temperature thermostat.
Evey thermostat that I have every tested worked exactly like that. Unless your temperature measurement equipment has a recent calibration certificate, there is no guarantee that it is in any way accurate. Even a laboratory-grade T or K-type thermocouple has a accuracy range. Home-grade stuff? You'd be lucky if it is +/- 10°F
Complete combustion is more likely to happen when the coolant is over 205°F. Below that you are dumping fuel out the tailpipe. Cooler is NOT better!
I'm pretty sure that it's a Stant but the 180 thermostat in the 250 in my 48 would open between 180 and down the road at highway speeds maintained 183 on a mechanical gauge most of the time. Big problem now with a lot of parts is the assortment has been cut down and we are seeing all too many one size fits all units no matter what the unit. Thermostats, spark plugs or anything else that we used to be able to get and exact heat range out of is now lumped into a between X and Z somewhere unit.
I have been using this brand for a while and have no issues. Slightly more money but worth it in my mind. https://flowkoolerwaterpumps.com/collections/thermostats
I just changed one that stuck. Driving home at night with the outside temp in the mid fifties and I look down at the temp gauge and it’s 215. Car has never been that hot even at 100+ outside temperatures and getting stuck in traffic.
here is the best thermostat made. And made in the USA https://www.summitracing.com/search...obertshaw-series-high-performance-thermostats
Verify your test equipment when you think some thing Off,! If you are really into Monterey things , keeping notes , test you will see moving temp sensor in different locations will give deferent readings , The Fan air flow will give different reading @ front of engine vs rear, even air blowing across front end on cylinders will be cooler then father back , Adjust thermostat to yr liking ,, Most engines like 215 -225 ish temps , but other factors are needed to control temps @'different air flow across Rad , I prefer to use a mechanical fan , but a clutch or electric much better to keep temps sufficient /steady. Coolant type plays apart on cooling temps.
I haven't noticed this late temp opening myself? I've tested some using my Fluke meter with a type K thermocouple and they opened very close to the stated temp rating.
The 'stats I've purchased lately have been lousy. The temp stamped on them is way off. Does Dole still make good thermostats? I try to keep an eye out for NOS.
I usually use Robertshaw stainless thermostats and test them to be sure they are what I think they are. I haven’t had any problems.
The older I get the less I know. Young Wipper-Snapper straightened me out the other day. He stated that his engine shouldn't reach 210 degrees because he just installed a 180-degree thermostat. I'm ready for some ice cream and a walk/trip up a flight of stairs.
I believe that thermostats start opening at the temp they are rated at... I read that somewhere years ago....160 starts opening at 160 and is completely open by 180...Normal operation....180 does the same and so on...
I only use the robertshaw style from Mr gasket. They have worked well for years. Ivs had more problems with accurate temp gauges lately
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