Hi all

i want to make "after shut off cooling curcuit"..or however this is called

so, i want to run a small electric pump in the a/C heater curcuit and one fan, until the coolant temperature is down to 180F (where my thermostat closes anyways)

the background is.. a friend of mine runs a Chevy pickup (modified) and also have this setup in it...

its amazing, how often this pump and the fan come on, after he shutted of the engine...

so, it seems, its a good amount of heat, that moves to the heads after shut down...

my question, is there a switch( on/off) available, that tuns on, at lets say 190F and off at 180, or sth in that ballpark?

a 3/8" threading would be the icing on the cake, since i have a spare hole in the cylinder head..

thank you

 

Yes. I don't have such a book, but I used one at a parts store to buy my fan switch. In the back of most parts books, you will want one that shows fan switches, there is a numerical section that lists the specs of the different switches. You will have to go through them, one by one, to find the, on, off, thread size, and connector style, you want/need. Low temp fan switches are sold by the Corvette specialists for $20.00 to $50.00. Before 1990, the Corvette aux fan was "fan switch" activated, but the temps were higher than you want. There are stock applications for what you are looking for. I think I paid $8.00 for mine, and I got what *I* wanted.

RACE ON!!!

 

Totally unnecesary.

 

What is totally unnecessary? The switch? If so, for which purpose? His or mine? Or do you mean saving ~ $40.00?

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I mean that the whole apparatus is unnecessary.

 

My exercise was simply to have my fan come on at a lower temp. I merely was advising on how I obtained my fan switch. I wasn't commenting or making a judgment on, the merits of corvette90's project, but just advising him that it could be done with stock parts. I don't see much of a need for it either, but maybe his circumstances...

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I agree. My comment wasn't meant as a dig to you. Just seemed like a lot of trouble to fix something that wasn't broken.

 

When I installed electric fans on my '79 I used a wire that had continous power and got tired of having the fans turn on and off until the coolant dropped below the temp the switch was set to. I finally wired them to power that was turned off when the key switch was turned off.
Bernie

 

Heat soak,I think that is what this is called, can be a concern I suppose. If so, why not keep the fans running until some acceptable temp was reached. Continued cool air would bring temps down without the need for circulating coolant. I would be more worried about some small pump leaking than heat soak.

 

That is very slow and inefficient. I use a manual switch on my fan to cool the engine between rounds at the drag strip. First, I spray the exterior of the radiator with a garden sprayer. Then I let the fan run for about 10 minutes. After the 10 minutes, the temp gauge has barely moved. I fire up the engine, for between 30 to 60 seconds, to circulate the water from the block to the radiator, while I watch the temp gauge drop like a rock. Two to three cycles like that and the gauge is reading 150° to 160°. By the time I drive through (I don't have to push) the staging lanes and do my burn out, the temp is back to 170° to 175°, just where I like it for staging. The point of that story, is that without a circulating pump, the fan running won't do any good after a short while. If I had an electric water pump, I'd run both and not have to re-fire the engine.

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Hi all

i dont say, that is the ultimative mod...

anyways...i give you an example..

the Audi 5000 turbo uses such a small electric pump to circulate coolant after shut off...ok, its also for the water cooled turbocharger, but also for the head...

now, lets compare..

the Audi cylinder head is small compared to an chevy head, and very small compared to the combination head-intake-head on a chevy...
álso, when you shut off the engine, the heat goes upwards in the head, the block contracts, the head-intake combo expands...

also, i´ve talked with some people that really know this Audi cars, and the say, this pump curcuit is very very important to avoid cracks between the valves in the cylinder head...now, compare the distance between the valves in the Audi head vs a Chevy perfomance head...

the Audi head have much more meat between the valves...

also, a lot of newer cars utilize this pumps...just for fun?? Don´t think so..


also, these pumps dont run when car is running..only, when shut off...

so, if you think, its a worthless mod, dont flame me..
opinions are welcome!!

 

no more opinions?

 

Make up your mind. Do you want no flames or do you want opinions?

Actually, I gave no opinion or made any judgment, I only gave advice on obtaining a switch and stated fact from experience.

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Open the clamshell and park in the shade............

And while we may not give the Corvette designers and engineers much credit at times, (like the #8 plug access) I'm sure if this was that big an issue, they would have addressed it.

 

Wasn't talking about the fans. It was the added inline water pump!

 

Your skin has to be thicker than that. How many millions of small block chevys have survived without this mod? I expressed my opinion. I get jumped on here all the time. Doesn't ruin my day. Maybe you should buy an Audi.

 

Then he can modify the Audi by removing the water circulation pump like Corvette owners removing their smog pumps. The grass is always greener.

RACE ON!!!

 

I have wondered about doing this also...or some-thing along the lines. I have just never found a fesable way to do it.
I can attest that out of the 100+ small block chevy engines i have torn into over the years as many as 90% of the iron heads cracked (very minute) at least one head between the number 3,5,4 or 6 intake and exhaust valves. I have only seen a couple of aluminum heads crack there but have noticed that this same area doesn't grind the same when doing the valves? this leaves alot of questions in my mind as to what is realy going on and i have heard many different ideas on why this happens. Shut-down heat soak is in the top 5 but i don't know if it is the ultimate culprit(most likely just one good way over heating period).
I say encourage the guy... Maybe he will stumble onto an easy solution from some other place than i (or others here)have looked... I usually refuse to even look at forign auto makes.
If there were an easy add-on to do this i would test it against amp draw and if it did not cause any rael drain i would do it asap. A little extra peice of mind neber hurts.

 

ROFL

JAKE