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I watched a 1hr video on how thermostats were made & yep I totally agree there are probably just a handful of places that actually make the thermostat part itself. Then they get shipped off to say Gates, Dayco, Murray, Motorad, Britpart, and all the OEM manufactures.
D2’s aren’t the only vehicle that can sometimes be hard to get the air out of. Jeep WJ 4.7L V8 is picky, and so are most small Honda/VW’s that have crazy routed coolant hoses.
It could take 3 good attempts to get the air out if there was a big enough air pocket in the system be it in the heater core, intake manifold, or in the radiator.
I do so many 180F thermostat installs in TX that it isn’t even funny. Not one single bad thermostat! A brand new thermostat is either going to open or stay closed. It’s not going to just partially open or close. That could happen with crap in the cooling system or an old original 20 year old thermostat, but if a brand new thermostat doesn’t open it’s because the thermostat is surrounded by air vs coolant.
I highly suggest removing the upper radiator hose off the T, then filling it until the lower hose has coolant flowing out, then install the thermostat. That usually will get rid of a large air pocket in the radiator. Which will make the thermostat to open. Then you can bleed the air out with several cool down/top off cycles.
I just did my friends new to him 04 that he drove to me. He had temps of 220F at idle... I let it cool down enough that I could depressurize the system, flush it, and install the 180F (gotta love a hot engine bay lol), I slapped in coolant, burped it, let it cool for 30min, and then drove that sucker! Temps were 188-193F and idle was 200F. That’s 20F cooler & I honestly rushed it, but the key is to burp it, and fill the radiator until coolant flows out then install the thermostat.
Agree...
The other thing no one accounts for is the crap they mount in front of the grille. That can also restrict flow and cause issues, but hey, knock yourself out!
I had a bad Britpart 180 stat, was getting circulation but I assume the thing wasn't opening all the way. Tossed in old Motorad stat, didn't overheat, put back Britpart, overheated. Exchanged for new one and no issues after that.
ok, had to wait till today for parts and time.
pulled the old tstat. as I was disassembling saw no signs of leaking from water pump, or other plumbing points. underside of rover has stayed dry since towed back.
though I'd test the old tstat, so tossed it in a pot of broiling water. It never seemed to open, but sure contaminated the pot w/ what looked like copper metallic powder.
Should i reflush the engine(I did a full distilled water flush when I swapped the rad, and changed from orange to green)??
thought I could only use distilled water in the engine?
there does seem to be a lot of scaling in the engine inlet pipe throat. not to the point of blockage... just a lot of barnacles on the pipe walls.
You can flush with hose water but its not a good idea generally to drive with hose water etc. Clean out stuff as best you can, it can only help!
Chances are, those deposits are from someone using hose water in the engine for extended periods of time -- its the minerals in the water being deposited where as distilled has none
ok, so after replacing the tstat w/ an OEM unit from AB, I filled the system(burping w/ the bleeder screw) and idled up to temp w/ heat blasting. Temps held, but no hot air. shut off and waited 45 minutes. topped off the reservoir and brought it up to temp. this time the heater was blasting hot air, and I drove the rover around the block several times... temps remained in the middle of the idiot dial. my working assumption is that the Thermostat must have failed, likely due to all the metallic buildup inside the unit.
think im going to buy a "soft spring" tstat and keep it in the back from now on.
next up...lets see if the pressure tester can tell me if my head gasket is still good, or otherwise find out where the slow leak/ consumption is coming from.
metallic gunk that came out of old tstat during boil test.
ok, so after replacing the tstat w/ an OEM unit from AB, I filled the system(burping w/ the bleeder screw) and idled up to temp w/ heat blasting. Temps held, but no hot air. shut off and waited 45 minutes. topped off the reservoir and brought it up to temp. this time the heater was blasting hot air, and I drove the rover around the block several times... temps remained in the middle of the idiot dial. my working assumption is that the Thermostat must have failed, likely due to all the metallic buildup inside the unit.
think im going to buy a "soft spring" tstat and keep it in the back from now on.
next up...lets see if the pressure tester can tell me if my head gasket is still good, or otherwise find out where the slow leak/ consumption is coming from.
metallic gunk that came out of old tstat during boil test.
1. Theres probably more air in there. Look inside the stat and see if the two holes have any clogs.
2. I doubt your stat failed. Stats are technology that have been working perfectly for years, the failure rate is no where near this forum makes them out to be. The real problem is air.
3. Jacking up the front can help move the air through the heater pipes and the intake, it changes the angle of which the air has to move. You have to bleed more and sometimes multiple times.
4. You cannot use the gauge to tell anything. By the time the gauge moves to a higher spot it is too late.
5. Get yourself a gauge that reads real temps. Then and only then, you'll see your progress.
6. You will put in a new stat and wind up with high temps. This isnt because motorad sent you a faulty unit, it's because the system still has air.
