Thermostat

[hogv8]

How many of you guys with carbed engines run a thermostat . If so do you have holes drilled in the thermostat , how many and what size hole .

Thanks , Jack

[Sonny]

Isn't the purpose of the small hole(s) basically to prevent an air pocket from forming possibly leading to erratic and inaccurate temp readings?

[Carl La Fong]

I've been following the thread on the other board with some interest and amusement. Yeah, I still check in there daily, but I only answer via PM.
All, liquid cooled, automotive engines are designed to be run with a thermostat. I don't think there is any mystical magic involved in their use or function. A 140 stat will not allow an engine to run cooler than a 180. That's simply the temperature at which they open. The cooler stat will open sooner, but the engine will reach whatever temperature that the radiator, fan, ambient air temperature, load, timing and fuel mixture dictates.
That being said, I don't have one in my engine. It didn't have one when I bought it and I figured, "What the hell." Here in sunny SoCal, it has never overheated, even with the Jabsco. Since I added the home brewed, belt driven, water pump, it runs about 100 degrees above ambient air temperature.
I have heard about drilling holes in the flange of the stat for years. I've always heard that a 1/8 hole is good. I doubt that 2 holes would hurt. It may slow down the warming up process a bit.
As to the theory about bypass, gasket shrinkage, water manifolding and so on, I remain somewhat skeptical. Mostly due to the inability of The Grand Poobah to link two words together into a cohesive and intelligible thought. As I read it, using the Google Adrian translator, the stock BH water manifold does something that the Chevy waterpump doesn't do. What that could be remains a dark mystery, to me. The Jabsco, combined with the BH plumbing pushes coolant into the engine. The stock GM pump does exactly the same thing. I don't know what this "bypass" deal is. Having built my own pump and manifold, I do have some familiarity with the cooling system. I also am quite certain that a little hole, or two, in the thermostat is not going to cause or alleviate overheating, gasket shrinkage(???) or head bolt loosening.
Additionally, (there's always more, huh?) I cannot, for the life of me, figure out why F/I and carbed engines would have any different heating or cooling issues. The engines are, nearly, identical. The cooling systems are identical.
I just think that a proper cooling system will work without a lot of monkeying around. I always felt that the Jabsco pump is a compromise that works pretty well. I knew I could do better, but it was only to satisfy my need to try something else.

[hogv8]

Thanks for your input John . I don't run a thermostat either but I have some concern about my engine running too cool here in upstate NY state climate . Cursing on a normal summer day (about 80 degrees ) my engine seldom gets over 160 degrees unless I'm in traffic , lower on cool days . Do you think I should be concerned ? Should I install a thermostat so I'm running closer to 180 while cruising ? If so do you think I should drill a hole or holes ?

Thanks , Jack

[Carl La Fong]

I've always understood that 180, or so, is optimum temperature. I'd stick a stat in it, if you're concerned. A hole or two, as I stated, probably wouldn't hurt. I should do the same. On cool days (65-70F), I sometimes run at 150-160. An engine that runs too cool will sometimes have problems with condensation and sludge

[3FOR2]

John..
Thanks for your post. I've really had to bite my tongue, and keep from posting a reply on the other site. Basically, the way I read it, Adrian said anyone that has paid beaucoup bucks for a new FI BH, the factory frigged it up, and you have yourself a timebomb. I just wanted to ask, am I the only one that questions this? Nice to know maybe I'm not crazy... Pat.

[Carl La Fong]

Adrian listens to people and believes everything they say. We had a heated argument about Nesco transmissions and how they sap 30% of the horsepower. I believe that a transmission, like a water pump, an alternator, a power steering pump is a parasitic device. It will require a given amount of power to operate, not a percentage. It makes no sense, whatsoever, to think that the same parasitic device will require different amounts of power. I used the example of the prime mover in the Queen Mary. If you could connect it to a Nesco and it could survive, do you think it would use 48 thousand horsepower out of the available 160 thousand? The answer was, "Yes". I finally gave up
I said I wouldn't goof on Adrian any more. I guess I fell off the wagon.
If you want, you can read all about it here
http://jkcallin.blogspot.com/2013/11/ot ... n-low.html

[Sonny]

As I stated on the other board my Stant SuperStat 180* keeps my temps pretty close to the 180* mark most of the time. Overall my temps vary between 165*-195* and that suits me just fine. I'm having a hard time grasping how the absence of a 1/8" hole could possibly cause catastrophic engine damage before the thermostat begins to open up on it's own. The factory normally drills a hole in the thermostat for the purpose of preventing an air pocket, not for preventing head gasket failures.

[3FOR2]

"I used the example of the prime mover in the Queen Mary. If you could connect it to a Nesco and it could survive, do you think it would use 48 thousand horsepower out of the available 160 thousand? The answer was, "Yes". I finally gave up"

Now that's funny!
.
.
.

[hogv8]

I've always understood that 180, or so, is optimum temperature. I'd stick a stat in it, if you're concerned. A hole or two, as I stated, probably wouldn't hurt. I should do the same. On cool days (65-70F), I sometimes run at 150-160. An engine that runs too cool will sometimes have problems with condensation and sludge

Thanks John

[wag]

I've never used a thermostat, not needed.

[SQ4MN]

ON THE OTHER HAND ACCORDING TO ADRIAN IF I HOOKED A NESCO TO A MODEL AIRPLANE ENGINE IT WOULD ONLY REQUIRE 1/1000 OF A HP TO TURN IT.

[CanuckHoss]

Thermostats are pretty much a must up where we are if you want to ride earlier in the spring and later in the fall.

I have had bikes without thermostats and they would not go over 110 -120 degrees on the highway when riding in the cooler temps which I prefer as i don't like the 100 degree stuff...been told those temperatures are not great for a motor.

[GordonBH]

It's always difficult tapping into a large resevoir of opinion/knowledge - with any data set provided by a large group of contributors you will get conflicting outcomes. As a result we often take the majority rule.

The oil and transmission fluid threads are good examples of the lack of definitive outputs. As the boy genius accurately spotted I am an over-thinker and frustrated engineer and seek precision so when I ask how to change all the trans oil I hope to get one way to do it. Now I have to choose between them so I've decided to go with the full replacement (why only do 2-3 Qts?) and the running engine method to max the amount of oil in there.

Anyway I might have hijacked the thread but somehow feel this forum will just smile and let me off with it.

So to get back on track, I'm getting a 180 and drilling a 1/8" hole in it as we are heading for mid-40s soon then down to mid-30s until Spring.

[Swiss V8]

I added a 160° thermostat on my SB but without hole. It takes a while to open and therefore the temperature in the motor goes higher than the fan thermostat (185°) and turns on my fan which is annoying.
As soon as it is open on a cold day (below 55°F) the temperature stays around 165° while riding out of town, without it dropped to 110° - 120°.
I might just add a hole or two when I get to open the water system again...

On the BB I decided to NOT mount a thermostat as the water temperature rises quite quickly. Therefore no question about a hole or not...

[hogv8]

I think 165 degrees in 55 Degree temps if perfect . That should mean that it would probably run about 180 in 80 Degree temps .

That's the reason I didn't like the 180 degree thermostat I tried . It would run 175 - 180 in 55 degree temps but in 80 degree temps it would run about 180 -190 degrees . I think a 160 is the way to go with a couple of 1/8" holes .