Engine running too cold XD

Stoffauge

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Good morning guys,

I did have cooling issues like hell ( 250+ after maybe 10min driving) resulted from a totally clogged old radiator. Replaced it with new high performance aluminium 3 row radiator, complete flush of engine block with all plugs out and new thermal fan clutch (OEM). Also replaced the original (and new Tstat (195 from STANT) with a Mr Gasket HIGH flow 180 (MRG-4367). Now the engine didnt get above 160maximum; more like 150. Too cold if you ask me. Put back in the 195 original normal flow Tstat but it seems to be stuck open because the engine now won´t heat up at all (slowly climbing up to 150 while rolling in a city but as ssoon as I hit the gas on the interstate or open road it goes back down to 100-120. Upper Hose and radiator gets warm kinda right away after starting engine . I am just wondering why the Tstat seams to be broken because i checked it before and it was closed and the spring was working good (although it has seen temperatures around 250+). Put in new Gasket and then Tstat within housing in correct direction ("to rad" faces up - that you can see that side when looking in the tstat housing). Housing (More Information for MOTORAD CH4830) a new piece also with correct flange etc and tstat fits good.

Don´t know , would just buy a new 195 Motorad normal flow tstat to see if mine is really broken although it looked very ok. Read that some tstats have a function that they lock in wide open after getting like 235-240 and will never come back ("fail safe" feature by name) and have to be replaced but I couldn´t figure out that my tstat from STANT got that feature and it was closed obviously also.

Any advices on that one?
Don´t really know what tstat to choose: 180 normal flow, 195 high flow /normal flow....
Just want my Engine to run in the 190-200 range.

Right away leaning towards this one as the best of two worlds. Higher temp but also high flow with jiggle pin (More Information for MOTORAD 2006195)

Fabian

P.S: got to Temp gauges - good working oem in dash/speedo and new autometer with all new wiring and sending unit great working.
 
I run 195 never had an over heating problem, even sitting in the Woodward dream cruise traffic.
 
Tstat but it seems to be stuck open
open the radiator cap and see if the coolant is flowing. if it is, your tstat is open. want to know if it works? drop in a pan of water on the stove with an appropriate thermometer. if it opens crooked, it's likely going to hang up. thermostats today are junk. they should sell them by the six pack. that way you might get one that works.
 
open the radiator cap and see if the coolant is flowing. if it is, your tstat is open. want to know if it works? drop in a pan of water on the stove with an appropriate thermometer. if it opens crooked, it's likely going to hang up. thermostats today are junk. they should sell them by the six pack. that way you might get one that works.
I checked it at the top of the rad and its not really flowing but it´s moving slowly and gets warm at the top right away. so i guess it´s somehow "leaking" not closing properly.

I know what you mean what do you want to expect when they sell these for like 2,50?

Gonna get a 195 one from Motorad. Didnt try them yet so they´ll get a chance. Don´t know which one to try else: Mr. Gasket 4367 was working but engine somehow staying at 155 and stant after 50miles already broken.
Or is there any magic trick to install them right or in a different way that they work better or more reliable?
 
IF you are concerned about the thermostat's operation, you can test it in a pan of water on a cook stove, with an accurate thermometer. Hang the thermostat over the edge of the cooking pan with a piece of heavy wire and use insulating gloves to touch the wire with. Of course, the water temp in the pan will need to approach (and maybe slightly exceed, for good measure) its boiling point (212 degrees F).

When I put an OEM-style composite radiator (plastic tank and hi-efficiency aluminum core) in my '77 Camaro 305 years ago, it took a full 45 minutes for the thermostat to open on a 75 degree F afternoon. Until it did, just a trickle of coolant under the radiator cap, but when it finally opened, a full flow. With a normal 180 degree F thermostat. I had the luxury of having a temp gauge in the car, too, so I could verify what was happening.

I used to seek out the RobertShaw-style thermostats (now Mr. Gasket sells that style) as that was what Chrysler used OEM. I always felt better about them being OEM and such, but the normal style seems to work just fine for many people and that is what Chrysler later went to, OEM. Key thing is that the thermostat works as designed.

As to thermostat temperature, the standard/normal temperature used to be 180 degrees F on almost every vehicle (except some mid-50s Buicks which had over-heat issues, so they used a 160 t/stat) until the later 1960s when emission controls dictated a 195 degree F thermostat and an operating temperature right at 200-210 degrees F (according to the factory temp gauge in my '77 Camaro). EITHER one would work well for you.

High Flow thermostats are good to have, but not always needed for many customers. A judgment call, to me, coonsidering that the normal ones work as good as they do for most customers. BTAIM

Just my experiences,
CBODY67
 
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I seem to remember something about a "skirt" on the thermostat? Good ones have it but cheap ones don't.
 
the motorad "fail safe" thermostats have 2 additional stainless clips visible on the bottom side ....when the thermostat opens "too far" from too much heat those clips catch the edge of the disc...and hold it so it can no longer close when things cool off...but the thermostat can still fail in the closed position so i really dont see an advantage to the design
 
I seem to remember something about a "skirt" on the thermostat? Good ones have it but cheap ones don't.
I suspect that "skirts", like "bleed holes", might be more about the quality of the fluid flow. Needed by some, but not others?
 
Stant closed up shop ...been dealing with some cooling issues on a 454 chevy but my problem is it only uses a 44mm thermostat...which robert shaw doesnt make...after the "fail safe" motorad not opening at the right temp i tried to find another kind ...from 3 different auto parts chains over here (dealing with this on the road)...their websites showed different styles (3 arm robert shaw style, ones with a jiggle pin,all high flow premium ones)...in different house brands...but when i picked them up they were all conventional 2 arm ones, no jiggle pin and all marked motorad... one of the high flow ones had a plastic ring inside of it that looked like it would actually restrict flow...hopefully your experience with the larger diameter one will be better cause with my small one it looks like keep buying motorads till you get one that actually works
 
Ordered a 195 high flow with jiggle pin made by Motorad and gonna check it first in a pot with water and will tell if u got first results . Will be my third time finding a working tstat and hopefully three times will be my Charme
 
so i guess it´s somehow "leaking" not closing properly.
leaking. that occured to me during the day. that the flange of the thermostat might not be seated properly or the gasket could be too thick keeping the water neck from forcing the flange into its seat the coolant is flowing so something is wrong there. keep in mind that the heater core radiates heat also. if the blower is on, it contributes to cooling. if you pull the thermostat again, an easy way to refill the engine is to fill it through the thermostat hole before you drop the thermostat in. that way you know that there will be no steam pocket behind the thermostsat.
 
leaking. that occured to me during the day. that the flange of the thermostat might not be seated properly or the gasket could be too thick keeping the water neck from forcing the flange into its seat the coolant is flowing so something is wrong there. keep in mind that the heater core radiates heat also. if the blower is on, it contributes to cooling. if you pull the thermostat again, an easy way to refill the engine is to fill it through the thermostat hole before you drop the thermostat in. that way you know that there will be no steam pocket behind the thermostsat.
That what I thought too but whats the best and safest way to set it up right? fill it up through the neck, put on the gasket (I do use fel pro) and I do use gasket sealer a bit on top of that gasket, then put the thermostat on top of the gasket and bolt on the housing.

Or do you put the tstat in the housing first and both on top of the gasket? Does it really make a difference because the tstat fits perfectly into the housing on the flange......

Can´t be that tricky.... :confused::confused::wtf:
 
I drill a couple of small holes in thermostats to alow air to bleed out before thermostat opens
 
I bought a tstat with a jiggle pin that should do the job but good advice though!
 
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