Thermostat

[Livin' in the 80's]

Originally Posted by Dynomite

Depends on how much you drained......and depends on the concentration before and the concentration you now want (Low Temperature Protection).

I usually go for -20 deg more or less with Zs not driven in winter but under cover in shed/garage. If you are in warmer climate you may go a bit less antifreeze but anti freeze also does serve multiple purposes (anti rust, raises boiling temperature) in addition to obvious protection from freezing temperatures. I usually will refill with a gallon or a bit more of antifreeze and about gallon or bit less distilled water then top off white plastic overflow container under passenger headlight with pure antifreeze within an inch or two of top of that plastic reservoir. This is if you only removed a bit of coolant for Plenum Removal...I have TB coolant blocked so do not have to remove any coolant for Plenum removal.

Which white plastic reservoir I check after each of two or three heating cycles to make sure it is still topped off. I check before and after refilling/re-filling with 5 ball tester (I recall) and shoot for 3-1/2 balls floating (that is 3 balls floating and the 4th ball in suspension).

3 balls floating.......-10 deg F and +261 deg F
4 balls floating.......-25 deg F and +266 deg F

Now if you drained more coolant as in replaced water pump and radiator.....use more than 2 gallons approaching 3-1/2 gallons coolant more or less. If you removed engine and are now replacing coolant......use more than 3 gallons.....maybe approaching 4 gallons more or less of coolant. but do remember to go through several heating cycles after coolant replacement to top off with in 2 inches of top of that plastic coolant overflow under passenger headlight. You fill the coolant using the Top Black Reservoir just in front of the passenger side windshield under the hood.
OR

I am only replacing the thermostat. I would think that this will pretty much drain the entire system as the housing is mounted low on the frame rail. No?

[Dynomite]

Originally Posted by Livin' in the 80's

I am only replacing the thermostat. I would think that this will pretty much drain the entire system as the housing is mounted low on the frame rail. No?

No.......there is coolant trapped around the cylinder liners and in other places in the engine simply because the water pump is higher than the thermostat as well as coolant trapped on ALL wetted areas of the Coolant System. The Engine coolant can only drain from a removed thermostat through the water pump. Also the inside of the radiator is not dry...it is wet and coolant still resides in an otherwise drained radiator. And....you have the Heater Core which holds coolant including the Heater hoses.

[XfireZ51]

My experience w thermostats, Fluidyne rad, and 1/8" holes was documented
here:
http://www.zr1.net/forum/showthread....ght=Thermostat

My particular issue began w installation of Fluidyne and driving in colder climes. At ambient temps of anything below 55F, I could not keep temps up. The coolant temp continues to drop whenever driving. Coolant temp would increase at idle.
On any drive it became necessary to cruise in 5th rather than 6th just to keep coolant temp up. Once into the summer driving season, the issue resolved itself. Some specifics. Fluidyne rad, 180F thermo w 4 1/8" holes, underdrive pulleys.
I ultimately bought another stock thermo from Jerry, and put in 2. 1/8" holes.
Temps at cruise stabilized at 185-190F in cold weather. Idle temps will creep up slowly but I surmise that's due to the underdrive pulleys. I think it could become an issue in the more severe driving conditions of hot, crawling traffic.

[Livin' in the 80's]

Originally Posted by Livin' in the 80's

I just emailed Stephen Woodward at Prestone and asked if it meets the GM spec.

Here is the response I got from Prestone:

Good Morning Craig,

GM 1825M is an old specification for standard, conventional green antifreeze. We recommend the Prestone Antifreeze/Coolant in the yellow jug for any application calling for that specification, but you could also use the Prime Conventional Green Antifreeze/Coolant if you want a coolant that more closely resembles the factory fluid. Please let me know if you require anything further.

Sincerely,

Aaron Jones
Prestone Consumer Relations Representative
Phone: 203-731-8191
cid:image001.png@01CDC249.2F757380

[Livin' in the 80's]

I just talked to Stant and the 14068 is now discontinued. More to come.

[HAWAIIZR-1]

Originally Posted by Livin' in the 80's

Here is the response I got from Prestone:



Good Morning Craig,



GM 1825M is an old specification for standard, conventional green antifreeze. We recommend the Prestone Antifreeze/Coolant in the yellow jug for any application calling for that specification, but you could also use the Prime Conventional Green Antifreeze/Coolant if you want a coolant that more closely resembles the factory fluid. Please let me know if you require anything further.



Sincerely,



Aaron Jones

Prestone Consumer Relations Representative

Phone: 203-731-8191

cid:image001.png@01CDC249.2F757380

Thanks fir sharing. I'm going to check one more source here and might have to settle for this one. Now, to drill or not to drill...that is the question.


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[Roadster]

Originally Posted by Livin' in the 80's

I just talked to Stant and the 14068 is now discontinued. More to come.

Jerry's has them in stock according to his web site. There are units available with the gasket shown on ebay and supposedly Gates 33068 is an exact duplicate of the Stant 14068. So there are parts still available.

[Livin' in the 80's]

Originally Posted by Roadster

Jerry's has them in stock according to his web site. There are units available with the gasket shown on ebay and supposedly Gates 33068 is an exact duplicate of the Stant 14068. So there are parts still available.

The ones on ebay are not the correct ones. Ordered one and sent it back.

[Dynomite]

Summit Racing has 180 deg Stant 14068 thermostat as does Marc......they are not in stock at Summit and will be shipped directly from manufacturer. I ordered one to test the market


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[Roadster]

Funny you should mention that I did the same thing from the PepBoys online store for the Stant and the Gates version from an eBay retailer.....should be interesting.....

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