Heating, water pumps and fans discussion

[kencombs]

All the discussion on these subjects bring to mind a question regarding pump efficiency.  I'm sure that later design pumps are available that move more water at given speed than our older ones.

 

Has anyone identified such a pump that could be adapted to our 218/230 engines.  Lots of similar things have been done for more modern engines, like BB Chevy on Mopar early hemis,  so adapter design should be doable.  I'm thinking that impellers with more vanes or different shaped vanes are common in lots of applications.  The trick is to wade through all the possibilities and select some that could be adapted,

 

Any ideas?

 

I typed out a fairly long discussion of electric fans and lost it.  Later maybe.

[Sniper]

When I bought a new pump for my 230 I also bought a new pump for a BB MoPar.  My thinking was that the flathead pump would have two vanes, like my FSM shows.  It has a nice 6 vane pump with a cast impeller.  My original thinking was that the BB MoPar pump would have a better impeller and that I could play swap the impellers.  But the BB MoPar pump had a stamped steel 6 vane impeller.  Not sure it would have done anything for me so I didn't do the swap.  So I got to thinking that a smaller pulley would increase the pump speed.  Since the engine RPM limit is low, comparatively speaking, I wasn't worried about cavitation.  Issue is finding that pulley.

 

Other than that, I have nothing.

[keithb7]

I’m reading these cooling threads. Taking it all in. I’m second guessing my thoughts about what I think is “getting hot”. 200F to me getting pretty hot.  But not to some others here. Being as 212F or so is boil over point isn’t it? Depends on system pressure (cap), elevation, % of glycol, etc.  

 

I agree, if I keep driving and air is moving through the rad, it doesn’t boil over.  Again, pending my travel speed and ambient air temp. My water pump has multiple vanes. 
 

I firmly feel that my cooling system is in tip-top shape. I’ve been through it all. Boiled the block. New WD tube. New W pump, belt, hoses, thermostat  re-core’d the rad all fins new & clean. New rad cap.  It all works well as a system . To re-state the obvious, it still gets up to 190F up the hill home. It ain’t even summer yet!

 

Edited April 16, 2022 by keithb7

[Sniper]

A 4 bladed fan with no shroud probably doesn't help. 

[sidevalvepete]

Keith.... maybe, as the mopar tech suggests, is your temp gauge reading correctly?

Edited April 16, 2022 by sidevalvepete

[keithb7]

Good point @sidevalvepetecould be out a bit. Yet my 170 thermostat seems to regulate nicely when steadily cruising on the hi-way. Seems to read steady in the 170 range on the gauge.
 

I like the idea of a 6 blade fan and a shroud.  

[rallyace]

My recently rebuilt 218 engine runs quite well at 185 F with a 185 F thermostat. I have not had any cooling issues. I did install a new pump with a cast impeller and a new water distribution tube, and the block and head were boiled out and clean on the inside. We even pulled out a couple pieces of the wire that reinforced the casting cores out of the head.  On a 90 degree day in a parade it will get close to 212 F but I have not had any issues. If it gets close to 200 a quick run up of revs to about 1800 RPM will bring the temp right back to normal. I should also mention that I have a three core aluminum radiator.

Edited April 16, 2022 by rallyace
additional information

[Doug&Deb]

My Coronet with a 180 thermostat runs 190 in anything over 70 degrees Fahrenheit. On a hill or stopped in traffic it gets to 200. No overheating. I have about 10,000 miles on a rebuild and I’m running an aluminum radiator. I also have a Stewart Warner temperature gauge under the dash so I believe it’s accurate. I’d rather run hot than cold. It’s better for the engine.

[wagoneer]

I’m going to get rid of the 4 blade finger chopper , and put a 6 or 8 blade 6v electric pusher fan on the front of the radiator. 
 

I found a 6v fan controller, temp sensor that screws into a plastic hose connector , and fans with shroud perfect to fit in the large gap in front of our engines (at least the c38/40s).

 

The fan with a complementary alternator to stabilize my power should solve any heating issues that aren’t internal, and the controller should allow it to run only when needed even at idle . 
 

I’ll put an override switch internal to power it on as needed.

[Bryan]

And remember the temperature gauge is connected at the back of the engine, which is the hottest point. Would be interesting to have an extra gauge connected at the middle or front. 

Edited April 17, 2022 by Bryan

[Sniper]

Not sure I'd point a torch at a mason jar full of moonshine, lol

[Bryan]

Water Pumps in Automotive Engine Coolant Systems - ASE Certification Training HQ | ASE Certification Training HQ    Says about 33 to 125 GPM. Edit: From other sites this is too high. 

 

Can a water pump have too high a gpm rating? - CorvetteForum - Chevrolet Corvette Forum Discussion  

 

Added: https://www.chevyhardcore.com/tech-stories/fuel-cooling-ignition-tech/tech-feature-what-you-should-know-about-electric-water-pumps/

 

Seeing other discussions about electric pumps having a constant flow rate, vs mechanical which increase at RPM.  Electric pumps being rated at no back pressure unlike mechanical.  Booster pumps causing issues with flow of stock pump if lower output.   HP vs needed cooling. Etc

Edited April 17, 2022 by Bryan

[Sniper]

1 hour ago, Bryan said:

Can a water pump have too high a gpm rating? - CorvetteForum - Chevrolet Corvette Forum Discussion  

 

lol, the old "moving too faster thru the radiator to cool the coolant" BS.

 

If that were true the coolant would also be moving too fast thru the engine to pick up heat.  Then your oil pressure would go away, rods would knock, pistons would melt, rings would stick, lol. 

 

The number one variable in calculating heat transfer for convection is temperature differential.  Here's a nice online calculator to determine that rate.  Note, time is not a variable.

 

https://www.engineersedge.com/heat_transfer/convection.htm

 

If you really want to geek out on it, read the article associate with the calculator.

[James_Douglas]

Ok,

 

There used to be an industrial water pump business on San Francisco Bay. The owner was into old Dodge Trucks. Now this guy built pumps you could walk into they were that big. He also did all kinds of smaller industrial pumps.

 

He decided that he did not like the impeller on the MOPAR flathead water pumps. So he designed one of his own. He cast them in bronze and then he ordered up from his supplier a Swiss sealed bearing and shaft. Basically all new guts and much better quality.

 

I have one someplace in my stuff. He was on his last legs and his son did the work on a pump for me. What happened was the housing which has to be bored for the larger bearing cracked after 5 years.  I pulled it and never got back to building a pump with the the guts.

 

It did move a lot more water.

 

They moved the business to Tracy California (https://armspumps.com/ ) one could call and see of they still have any of the impellers and the matching bearing-shafts and will build a pump if you send it out to them...

 

James

[kencombs]

28 minutes ago, Sniper said:

 

lol, the old "moving too faster thru the radiator to cool the coolant" BS.

 

If that were true the coolant would also be moving too fast thru the engine to pick up heat.  Then your oil pressure would go away, rods would knock, pistons would melt, rings would stick, lol. 

 

The number one variable in calculating heat transfer for convection is temperature differential.  Here's a nice online calculator to determine that rate.  Note, time is not a variable.

 

https://www.engineersedge.com/heat_transfer/convection.htm

 

If you really want to geek out on it, read the article associate with the calculator.

That red sentence is one of the reasons I plan to run a higher temp thermostat.  more heat is transferred to the air through the radiator if the entering temp is higher. 

 

That moving too fast conclusion has been reached by many when the radiator was restricted and water poured out the overflow or open cap at higher speeds.  Especially true with flathead Fords with two pumps.  They quickly overcome a clogged core and therefore 'the water was moving too fast'.

[kencombs]

4 hours ago, Bryan said:

And remember the temperature gauge is connected at the back of the engine, which is the hottest point. Would be interesting to have an extra gauge connected at the middle or front. 

 

 

Easier way is to buy one of the infrared temp gauges.  Point it at head in various spots as well as the radiator.  Very illuminating.  On most engines I've checked the hottest spot was not remote from the pump or thermostat surprisingly, but near the thermostat. 

[Bryan]

30 minutes ago, Sniper said:

 

lol, the old "moving too faster thru the radiator to cool the coolant" BS.

 

If that were true the coolant would also be moving too fast thru the engine to pick up heat.  Then your oil pressure would go away, rods would knock, pistons would melt, rings would stick, lol. 

 

The number one variable in calculating heat transfer for convection is temperature differential.  Here's a nice online calculator to determine that rate.  Note, time is not a variable.

 

https://www.engineersedge.com/heat_transfer/convection.htm

 

If you really want to geek out on it, read the article associate with the calculator.

Yep, some people on that site were calling it.  Read the article.   The best transfer would be trying to get the water as cold as possible next to the hot surface.  Plus a rough surface (larger area) and turbulent flow.  Only place you cool the water is the radiator.  In a radiator it'd be opposite than the motor block.  The cooler air temperature flowing thru the fins, cooling the metal. The hot water passing heat to the metal. It would be delta T of the water and the fins.

[Bryan]

3 minutes ago, kencombs said:

Easier way is to buy one of the infrared temp gauges.  Point it at head in various spots as well as the radiator.  Very illuminating.  On most engines I've checked the hottest spot was not remote from the pump or thermostat surprisingly, but near the thermostat. 

Now that I think about it, you're right. The water would continue to absorb heat on its trip back to the front.  It goes in the D tube, and even at the rear is pulled towards the Thermostat in the front. 

[Bryan]

If I were the wild type I'd probably use the existing pump body, take out the impeller, and hook some kind of electric booster pump to the input of the body. It amazes me that they only have a constant RPM electric motor for pumps.   Electric bicycle hall effect motors have a throttle. Seems like you could rig something that would respond to increased motor RPM.  More RPM input, electric motor increases speed.  I wouldn't do that but thinking about it is fun. ?

[Sniper]

16 minutes ago, Bryan said:

It amazes me that they only have a constant RPM electric motor for pumps.

 

They were originally designed for drag racing so sophistication wasn't needed.  You could use a PWM controller to vary the speed based on temperature.

[Sniper]

40 minutes ago, kencombs said:

That moving too fast conclusion has been reached by many when the radiator was restricted and water poured out the overflow or open cap at higher speeds.  Especially true with flathead Fords with two pumps.  They quickly overcome a clogged core and therefore 'the water was moving too fast'.

 

Yes, that also plays into the lower radiator hose needs a spring to keep it from collapsing claims.  If your lower hose is collapsing you either have a rotten hose or a restriction to the pump.  The spring put there by the factory was to allow the vacuum fill they use to work properly by keeping the hose open during the fill process.  That's it.

[Booger]

8 hours ago, Sniper said:

Not sure I'd point a torch at a mason jar full of moonshine, lol

SC? Moonshine? Not a chance : )