65' 365hp - Correct Thermostat

[David K.]

Hi guys;

I'm ordering a new thermostat from Long Island Corvette & see several choices (180deg, 195deg and 160deg). Which one is correct for my 65 365hp?

Thanks in advance.

NB - I just read a previous post which confirmed the 180 degree unit. The post confirms the Robert Shaw #330 - 180deg "Balanced Flow Type". Is this the way to go ?

[Edward J.]

Re: 65' 365hp - Correct Thermostat

David, I would go with the 180 degree, I am sure that is what the factory used. 160 to cold and 195 to hot.

[Wayne M.]

Re: 65' 365hp - Correct Thermostat

Page 31 of the '65 owner's manual; "Your Corvette engine cooling system is equipped with a 180 degree thermostat"

Now if it needed a 160, here's plenty .

Here's a closeup:


c

[Ken A.]

Re: 65' 365hp - Correct Thermostat

I'll take 10, if they're cheap!

[Stuart F.]

Re: 65' 365hp - Correct Thermostat

I'll take as many as you want to get rid of (I'll pay shipping too - notice I use "too" with two "0's").

I only recently changed back to a 180 from the 160's that I'd used since my first coolant change back in the 60's. The first 180 I put in stuck closed and My engine was only saved by my SHP by-pass. The second one is a Robertshaw type and that's working well, so far. Visual observation of my temp gauge shows little if any increase in operating temperature. My engine has 47,000+ miles on it and it hasn't been apart since new (over 50 years). When I remove my rocker covers to adjust lash, the top of my heads look like new, I.e. No sludge, etc. What can I say.

Stu Fox

[Philip A.]

Re: 65' 365hp - Correct Thermostat

At the risk of sounding sacrileges, isn't any branded auto part store thermostat suitable here? I do not think this is a "corvette" part that needs to be obtained form a corvette supplier. Am I missing something?

[Harry S.]

Re: 65' 365hp - Correct Thermostat

At the risk of sounding sacrileges, isn't any branded auto part store thermostat suitable here? I do not think this is a "corvette" part that needs to be obtained form a corvette supplier. Am I missing something?

Philip, your probably right. I like the Robert Shaw because when it fails, it fails open.

[David L.]

Re: 65' 365hp - Correct Thermostat

My 1965 Chevrolet Parts Catalog (May 1965) lists GM # 3156280 as the thermostat part number in Gr. 1.246 for 65 ALL, CORVETTE models as well as older models (180 degrees poppet pellet type). GM # 3156280 appears in my 1963 Chevrolet Parts Catalog (Oct. 1962) only for 63 ALL, CORVETTE models (exc. 292). GM # 3156280 was replaced with GM # 3033780 in April 1977 as per GM Parts History. The NOS thermostat in the photo below is stamped "DELCOSTAT" and "CF" on the top and "HRD" and "180" on the bottom. This thermostat was also correct for the 70 Camaro Z28 but not the 70 Camaro SS350.

Dave

[David L.]

Re: 65' 365hp - Correct Thermostat

Here is a photo of the bottom of the thermostat.

[Joe R.]

Re: 65' 365hp - Correct Thermostat

Here's the Robert Shaw (Flow Kooler) thermostat Stu mentions:

http://www.summitracing.com/parts/bra-330-180

It appears Summit doesn't have it right now, but it is on ebay.

Joe

[Harry S.]

Re: 65' 365hp - Correct Thermostat

This is who makes them........

http://www.flowkoolerwaterpumps.com/store/Thermostats/c22/index.html

[Joe L.]

Re: 65' 365hp - Correct Thermostat

Hi guys;

I'm ordering a new thermostat from Long Island Corvette & see several choices (180deg, 195deg and 160deg). Which one is correct for my 65 365hp?

Thanks in advance.

NB - I just read a previous post which confirmed the 180 degree unit. The post confirms the Robert Shaw #330 - 180deg "Balanced Flow Type". Is this the way to go ?

David------

For your application the original thermostat was a 180 degree. That's what was used then and that's exactly what I recommend now. 160 degree is too low for a modern engine (and, even 50 year old engines are modern in this context) and a Corvette cooling system will only be able to maintain a 160 degree temperature if the ambient temperature is frigid.

However, I do not recommend the poppet-pellet type thermostat (the type that Wayne pictured). The Robertshaw 330-180 is the way to go.

[David K.]

Re: 65' 365hp - Correct Thermostat

Thank you gentlemen;

I'll source the Robert Shaw unit (180deg).

Regards from Montreal; David

[Mike E.]

Re: 65' 365hp - Correct Thermostat

Did something change on the design of thermostats? I can remember my dad having to replace them regularly in a couple of his sixties Chevy station wagons. Back then they would fail closed and the car would overheat, not good! Then in the late 1970's the failure mode seem to fail open. I had a 79 Corvette that was a daily year round driver. One year I froze halfway through the winter until someone recommended changing the thermostat. Sure enough it fixed the problem, nice and toasty warm after that.

Mike

[Joe L.]

Re: 65' 365hp - Correct Thermostat

Did something change on the design of thermostats? I can remember my dad having to replace them regularly in a couple of his sixties Chevy station wagons. Back then they would fail closed and the car would overheat, not good! Then in the late 1970's the failure mode seem to fail open. I had a 79 Corvette that was a daily year round driver. One year I froze halfway through the winter until someone recommended changing the thermostat. Sure enough it fixed the problem, nice and toasty warm after that.

Mike

Mike------


Thermostats are now and always have been a MAINTENANCE ITEM.