Heater flow/temp issue?

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tayto

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be warned the mr gasket high flow stats are HOT garbage!
 

L31MaxExpress

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be warned the mr gasket high flow stats are HOT garbage!
Something changed on them recently? I ran them for years in everything except my L31 and never had a bit of an issue. Only reason I never ran them in my L31 is they do not have the coolant block off ring on the lower side that shuts off the water bypass when the engine is up to temperature which would allow a 5/8" diameter hose worth of hot coolant to return directly to the water pump full time. The L31s always got a Delco until they stopped making the OE units and out-sourced to cheap garbage. Along that same time frame I discovered that the L31 liked running cooler than 210*F and started using the Stant sourced Murray Ultras in 170*F. Recently the 170F Ultra was discontinued and 170F is only available in the Murray Plus line. I have tried both the 170F Plus and the 195F Ultra. Going down the highway the 170F stays cooler. Around town at prolonged idle and low speeds the Ultra is made to have a larger opening thus flows more coolant. This past summer, the 195F Ultra actually kept my 383 cooler around town than the 170F Plus. The 195F parks itself right around 198-201*F. The 170F was anywhere between 178F and 222F.
 
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454cid

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I don't think Robertshaw has made automotive thermostats for quite some time. Unless maybe they make them specifically for FlowKooler? I'm guessing FlowKooler licenses the name. It used to be that you could get a Robertshaw at a parts store. I have a one kicking around without a box, that I think is for my Buick LeSabre.
 

tayto

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Something changed on them recently? I ran them for years in everything except my L31 and never had a bit of an issue. Only reason I never ran them in my L31 is they do not have the coolant block off ring on the lower side that shuts off the water bypass when the engine is up to temperature which would allow a 5/8" diameter hose worth of hot coolant to return directly to the water pump full time. The L31s always got a Delco until they stopped making the OE units and out-sourced to cheap garbage. Along that same time frame I discovered that the L31 liked running cooler than 210*F and started using the Stant sourced Murray Ultras in 170*F. Recently the 170F Ultra was discontinued and 170F is only available in the Murray Plus line. I have tried both the 170F Plus and the 195F Ultra. Going down the highway the 170F stays cooler. Around town at prolonged idle and low speeds the Ultra is made to have a larger opening thus flows more coolant. This past summer, the 195F Ultra actually kept my 383 cooler around town than the 170F Plus. The 195F parks itself right around 198-201*F. The 170F was anywhere between 178F and 222F.
we went through 2 of them in friends 92 gmc, before i put an ac delco back in (which had the stant "S" logo stamped on it). i had been warned previously by a local speed shop to avoid them, but figured i'd try them anyway. both got cocked sideways and hung open. didn't get any pics so I don't really have any evidence... i personally run the flowkooler in my truck for 3 years, so far so good.
 

1990Z71Swede

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Turns out AC Delco thermostats ARE available, it's just that the European parts stores gets all confused with the fitment guides for a C/K1500 :rolleyes:

Now if I could just figure out what gasket to use I would be golden... :)

But I do have a sneaking suspicion that the rubber style gasket is used from 1992 and onwards. (from 88 on 305 Camaros)
Because I found this which appears to be the same thermostat but including the rubber gasket:
 
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1990Z71Swede

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I beleive the Gates thermostat will be a rebranded Stant. However Stant has been purchased by Motorad, and Motorad's products are hit and miss. Motorad makes a lot of Orielly's cooling products. A thermostat from Motorad, Gates, Stant is probably ok. I've purchased a few Motorad thermostats and they've been fine. I don't know if Motorad has comepletly replaced Stant's thermostats with their own or not. Stant used to be one of the best brands.
Well, in the Gates box that says made in the U.S.A, there was this. You sir, know your thermostats, for sure. :):worship:
 

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454cid

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Well, in the Gates box that says made in the U.S.A, there was this. You sir, know your thermostats, for sure. :):worship:

Its from parts shopping myself, and looking up company histories. Often times, the Stant name has been visible in Gate's pictures.
 

L31MaxExpress

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Its from parts shopping myself, and looking up company histories. Often times, the Stant name has been visible in Gate's pictures.
Which is somewhat to what I was alluding to earlier. It is also the same discussion previously on Vortec Injector Spiders. There are only a few companies that make everything now. Some people claim Napa is better, some Autozone, some say AC Delco, pick your poision. Most of them travel down the same assembly line and get packaged in the box for whoever is retailing them. Often it is even a plain white box.
 

Schurkey

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There "can" be "genuine" parts, Aftermarket (quality) parts, and bottom-feeder "knockoff" parts. It was that way decades ago--there was always someone who made the part cheaper and was willing to sacrifice quality to do it.

Things got infinitely worse when Dirtbag Clinton gave China "Most Favored Nation" trading status. And Congress helped companies offshore.

We're approximately at the point where the Genuine parts, the quality aftermarket replacements, and the crappy knockoffs are made in the same factory by the same workers; but instead of bringing the quality of the knockoffs "up", the quality of the good parts went down.
 

GoToGuy

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As your not going the high performance engine route, or live in the Mojave Desert, a 195° F. , Thermostat, and standard truck water pump will be satisfactory. The Gates products are a quality product.
Just be a little cautious when selecting ACDelco products, as they have three levels of part quality. Playing the discount part high margin game?
If you believe that your HVAC fan runs at correct RPM but does not feel like the volume of airflow is inadequate, there may be debris in fan box blocking airflow. Leaf matter, fuzz gets through the fresh air intake and can build up. Just a maintenance tip.
Good luck.
 
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