When is it too hot

How do I know when my Mav is running too hot. I have a 180* thermo. Normal running temp when going down the road is about 190*. Now that daily afternoon temps are in the mid 90's and getting hotter, the car idles at lights with the temp climbimg up as high as 210. Is this something to be concerned about? How much higher could I let it go before it is something to worry about?

Thanks

 

mine runs at 210 as well.....people say its ok....but not for a long time

i dont like any temps in my engine over 200....so i get concerned

 

I hate to see 200, but don't really know what is "safe"

Mine spews into the overflow tank around 220, so that is definitely too hot.

 

Short answer, It varies, depending on build tolerances.

another short answer, I get a little iffy when mine goes over 215-220. Most of the time it'll bump 215-220 when playing, then drop to 190-200 as soon as I stop. If it hits 220 during general use, I don't like it at all.

btw, one Saturday a few years ago it hit 250+ and stayed there for 20 minutes or so. replaced the main and rod bearings cuz I was scared and couldn't afford a full rebuild... no worse for the wear than it was before.

 

Water boils at 212 degrees. Pressurizing it raises the boiling point but personally I'd keep it under 200 if possible. There's no reason why a stock motor should run hotter providing the cooling system is in proper working order. A properly sized radiator, fan, shroud, water pump and clean passages should keep things cool. I have 10:1 compression but with the high quality Griffin radiator and electric fan, temps stay easily between 170- 190.

 

Just a thought and some insight. Newer cars run in the 200 to 230 range. You just don't see it cause the gauge just says N O R M A L. No problems running 210. Also if your car stays cool when driving but heats up at idle it could be one of theses things TIMING, not enough airflow at idle through rad, or waterpump flow is limited. or your cap is crap

 

When I worked at an auto parts store I recomended alot of people with heating problems like that while running a 160 thermostat to run a 180. My explanation in auto class is that with the 160 the water is moving too fast through the block and head to exchange the heat. It worked for most people that tried it. This is of course after you have tried a shroud and either a better fan, or a new fan clutch.

 

One guys says flow is limited, the other says to slow it down a bit.

Which is it? We have heard both arguments.

Personally, as an experiment, I took my 160 cut a bunch of holes in it (6@1/8" dia) around the flow hole, and solved my problem (which is really a lean fuel mixture, this was a bandaid fix). I noticed that with NO thermostat, I continued to overheat. but with a "modified hi-flo" stat (ie extra holes, but still some flow restriction), it ran cooler than with none or with a replacement.

I would guess somewhere between "hi flow" and "slow flow" lies the answer.

 

Late model cars also run a higher pressure cap as well ...

 

What is the correct pressure

What is the stock radiator cap pressure, I think mine has a 16 psi, but it is an aftermarket.

 

13 lbs was factory ... a 16lb cap raises the boiling point an additional 6 degrees or so ... as long as you don't blow out a hose or heater core ...

 

If you're worried about it at all, higher temps mean better fuel economy as well, as long as it isn't too hot. Burns less fuel, burns cleaner, but makes less power.

I'm not worried if mine peaks at 210 in normal driving, as long as it goes no higher.

 

Heater core? What's that?

I have seen guys drill holes in the t stat before and I have also seen the stat come with one in it already, if it doesn't have one I don't put one in it cause then I become confused with what my temp actually is and what it could be and why it is and why it's not and why why why, you know?

 

i tried my engine with a 160 stat....no stat....currently 180- stat... and i had a 195 in the original 170 engine...

of course...i had the 15 inch fan then and no shroud....so once i get the engine running i will be in a better place to answer

but every "expert" i have asked all say the same thing... allow the water to cool off in the radiator before going back to the engine...ie slow down the water....ie.... a higher stat and underdrive pulleys....

then other people say the opposite...so i am in the same predicament as you guys...what is the truth..

truth is...whatever works....dont fix it.... it works...
lol
frustration...and its late...im off to bed....ttyl

 

13 to 17 lbs is typical from what I have seen. Either way you can always step up to a higher pressure cap