Get a high flow water pump or stay with stock?

[Paul G]

Right now I have the motor apart doing some other work. This would be the time to switch out the water pump. It's a mild street built 360, 727. Decent tune. I have been fighting heat ever since I got the A/C working. Understand that I am in  Phoenix . In the summer with the A/C on high and it's 115 outside I cant keep the engine below 220 to 225. Wants to run at that or even higher when idling at a light. At speed it settles out to around 205. It has a big newer stock type A/C radiator 26" I believe, 50/50 mix, 5 blade viscous fan, stock shroud, 160 stat, and bottle of Water Wetter. If switching to a high flow pump will help I want to do it now.

BTW, Since last summer I have switched out the trashed out torque converter and installed a small in-line tranny cooler. Those items may have helped out as well?

Opinions? Will a high flow water pump cause more problems?   

[BigBlockSam]

I cant keep the engine below 220 to 225. Wants to run at that or even higher when idling at a light. At speed it settles out to around 205. It has a big newer stock type A/C radiator 26" I believe, 50/50 mix, 5 blade viscous fan, stock shroud, 160 stat, and bottle of Water Wetter.

sounds similar to my set up . when i do a motor i always switch to a hp water pump . last summer at 100 degrees temp out side .my 440 charger , stuck in traffic ran at about 215 and went down to about 205 when moving . 

[tan top]

 

i use one of these in mine  http://chucker54.stores.yahoo.net/milodon2.html
along with a 180  degree thermostat & a 50/50 mix with antifreeze  , 

[BigBlockSam]

i use a 165 thermostat . i want that water circulating as soon as possible

[terrible one]

I wonder if the Milodon HV pump that is $90 on Summit and Mancini Racing is not just a $33 GMB pump. When I first inspected my Milodon HV when I got it I noticed that it has GMB cast into the housing.

Check it out, 1st pump down is the Milodon HV #16260 and the 3rd pump down is the $33 GMB # 120-1200. They look the same from what you can see and like I said, my Milodon HV pumpwas clearly cast GMB. Has anyone else noticed this?  

http://www.summitracing.com/search/make/DODGE/engine-size/6-3L-383/engine-family/Mopar-big-block-B/Part-Type/Water-Pumps-Mechanical/?Ns=Price|Asc

[Paul G]

That made me think! What water pump do I already have? 

I went and looked at it. It is stamped GMB Japan on the bottom of the lower hose housing. Summit shows GMB makes a standard volume and a high volume pump for the small blocks. Both look the same. I wonder which one I have? I hate to replace a high volume pump if I already have one on there. How many water pump makers are there anyway? GMB may be making all of them?

A new Milodon high flow pump and stat is under $100. I am going to do it anyway. Or I will be kicking myself next July when the engine is running over 225 again.     

[charger2fast4u]

I would either go with a Milodon or a GMB I haven't made my mind up yet on which to get when I replace mine. I've read the GMB flows better due to tighter propeller/housing clearances more area to move more I am interested how the GMB matches up to the Milodon in propeller sizes? Reason I ask this is because of this thread check it out anyone do a side by side comparison of these 2? I'm interested if the GMB actually is better or not?      http://www.dodgecharger.com/forum/index.php/topic,75835.0.html

[hemi354az]

Did you read  -Overheating issue resolved....interesting read !- near the top of the Engine Section ?
I tested a lot of these pumps Pages 8 and 9 above. I'm in Shopsdale off 101 at Shea. Call and you can come by and see all the pumps tested. (XXX)8608772. Cruser.

[bull]

Stock. It's my opinion that the Chrysler engineers knew what they were doing. The so-called high volume water pumps have next to nothing over stock when it comes to GPM rates as far as I'm concerned, based on what I saw posted by hemi354az here: http://www.dodgecharger.com/forum/index.php/topic,60599.175.html Some of them are much worse but from what I've been able to gather, if you really want aftermarket stuff, Mancini is the way to go.

The housing is very important too and the stock housing is more than adequate based on comparisons to some so-called high volume housings out there on the market, especially the one made by 440 Source.

[Dans 68]

Stock. It's my opinion that the Chrysler engineers knew what they were doing. The so-called high volume water pumps have next to nothing over stock when it comes to GPM rates as far as I'm concerned, based on what I saw posted by hemi354az here: http://www.dodgecharger.com/forum/index.php/topic,60599.175.html Some of them are much worse but from what I've been able to gather, if you really want aftermarket stuff, Mancini is the way to go.

The housing is very important too and the stock housing is more than adequate based on comparisons to some so-called high volume housings out there on the market, especially the one made by 440 Source.

  For a stock or mild build the original unit is the best choice.

Dan

[tan top]

I wonder if the Milodon HV pump that is $90 on Summit and Mancini Racing is not just a $33 GMB pump. When I first inspected my Milodon HV when I got it I noticed that it has GMB cast into the housing.

Check it out, 1st pump down is the Milodon HV #16260 and the 3rd pump down is the $33 GMB # 120-1200. They look the same from what you can see and like I said, my Milodon HV pumpwas clearly cast GMB. Has anyone else noticed this?  

http://www.summitracing.com/search/make/DODGE/engine-size/6-3L-383/engine-family/Mopar-big-block-B/Part-Type/Water-Pumps-Mechanical/?Ns=Price|Asc

do you know what  i think i had that on my one  , i remember the pump having , china or japan cast into it also , though this was strange & took a grinder to it  
had a anti cavatation plate welded to the back of the blades

[b5blue]

Keep in mind ignition timing can effect cooling.

[elacruze]

The forgotten ingredient in all these cooling threads which I think is applicable here is to note that viscous clutch fans

*don't actually engage until 220-225 degrees*.

<edit> See my post below, apparently I've been looking at worn-out clutches myself. They are variable speed, not on-off.

It doesn't matter when your thermostat opens if you have little or no air movement. Also, performance deteriorates over time if there is any fluid leakage whatsoever or if the valve spring gets rusty or damaged. Have you stood outside with the hood open and verified that the fan clutch engages at all?

I believe the MP viscous kit engages at a somewhat lower temperature, but I haven't verified that scientifically. For your car, in Phoenix with A/C, I'd add an auxilliary electric fan. Add a pusher to the front of the condenser with relay and toggle and I think you'll see a nice temp drop.

Does the temperature act this way when it's cold out? If so, does it take longer to get high? If I'm right then cold temps should help you noticeably but won't completely solve the issue.

[Ghoste]

You could be right about the lower operating temp for the MP unit.  My car ran much cooler after getting mine back in.  The other factor in my cae that would make a big difference though is that flex fans do wear out.  I had an older factory one and I'm  sure the blades were likely flattening out at a lower rpm than they did when it was new.

[Paul G]

Does the temperature act this way when it's cold out? If so, does it take longer to get high? If I'm right then cold temps should help you noticeably but won't completely solve the issue.

With just the A/C turned off in the summer it stays around 205. Dont really know about driving it much in cool weather?

I think I am going to pull the pump off and see how many vanes it has, and what style before I buy anything. I also thinking that a high flow stat in itself may help a bit?  

What about the clutch? I can turn it by hand easily, but cant make it spin by hand, maybe one blade length. It has more resistance to turning in one direction than the other. Sound normal?  

Did you read  -Overheating issue resolved....interesting read !- near the top of the Engine Section ?
I tested a lot of these pumps Pages 8 and 9 above. I'm in Shopsdale off 101 at Shea. Call and you can come by and see all the pumps tested. (XXX)8608772. Cruser.

From what I see in your report, more vanes is better. No?

[elacruze]

Here's a quick diagnostic from the Hayden website-

http://www.haydenauto.com/Fan%20Clutch%20Tutorial-Part%203/Content.aspx

More specifically;

http://www.haydenauto.com/upload/HaydenAuto/Documents/Cat_Hayden/2007-hayden-fan-clutch.pdf


Thermal Fan Clutch
 Varies the fan speed with temperature of the air behind the radiator. 
 Engaged (high speed) operation provides maximum cooling
 Disengaged (low speed) operation provides fuel savings and noise reduction.
 Greater life expectancy than a non-thermal clutch
 Briefly engaged at cold start-up.
 Engages at about 170° radiator air temperature (about 30° lower than coolant temperature).
The air temperature coming through the radiator is sensed by the bi-metal thermal
spring on the front of the thermal fan clutch.  It expands and contracts with the change
in air temperature operating a valve inside of the clutch.  When cold, the silicone
drive fluid is pumped from the working area to the reservoir.  When hot, the valve opens
allowing fluid from the reservoir to be transferred to the working area thereby increasing
the fan speed. The clutch disengages as the air temperature decreases, closing the valve
and allowing the silicone fluid to be pumped back into the reservoir.
A thermal fan clutch is engaged on a cold startup because the fluid drains into the
working area when the engine is shut off.  The fan clutch will slow down shortly after
startup as a result of a pumping action produced by a difference
in speed between the shaft and the body of the clutch.
Most models are designed to duplicate original equipment performance. 
Some Chevrolet/GMC truck models are specifically designed to engage at lower
temperatures than the original equipment parts that they replace.

[Paul G]

This is the water pump I have. I count 8 vanes. It is a GMB. Could it already be a high volume pump?

Next pic is the fan and clutch. Fan #4140063, clutch 4095704. I think they are the Mopar Performance package? The clutch sure looks like the standard duty Hayden from the links above.

Would the Hayden clutch #2747, heavy duty, be a better choice for max cooling at idle? The clutch is about 1 1/2" from the radiator at it's closest point. I am also thinking of putting a 1/2" spacer to get the fan just a little closer to the radiator. As it is now most of the fan is outside the shroud, closer to the engine.

[elacruze]

FWIW I don't think you have a water circulation problem. I think you have an airflow problem. Your fan should be about halfway out of the shroud for maximum effect, so a spacer may help a little. Does your fan clutch pass the criteria in the links I posted? Try letting it sit and get hot, then put a kitchen fan in front of the radiator to see if that by itself lowers the temperature. Is your radiator properly sealed to prevent hot air recirculating from the engine compartment? Stuff some towels/cardboard around the edges where air might come back around front while stationary.

I have to admit that I know little about the construction of small-block water pumps but it appears that yours has room for a larger diameter impeller? I don't remember what the block side looks like. After a lot of noggin-thumping I bought a GMB for my Big Block.

If you have a circulation problem, you should be able to prove that by revving the engine in neutral when hot and see the temp drop.

More to consider is how hot and clean your A/C condenser is. If your system is hotter than optimum, you're adding heat to the radiator. ditto with the transmission-do you have a loose converter? Trans heat also translates directly into coolant temperature if you have an internal cooler in the radiator.

As others have said, ignition timing can affect temps too-if you're too retarded at idle, you pass combustion into the exhaust ports which is picked up by the coolant-which may get better with RPM as both airflow and timing increase. 

Always interested to know the root cause.

[elacruze]

<snap>

[oldcarnut]

I changed out the stock fan clutch in my 70 RR and put in a torqflo 922797 from Autozone. It was listed as a severe duty fan clutch at the time but is used on a lot of big Buick cars and Dodge trucks and others.  It's thicker than the stock and was pretty stiff to turn.  It helped with cooling for me.  I didn't have problems but it decreased the clearance between the radiator and clutch end as its a lot thicker but if all else fails you can take a look at one at the store for yourself.  Hopefully it will still do the job once the nosecone etc is mounted on mine.

[charger2fast4u]

Elacruze I been wanting to ask you what made you go with the GMB pump over the Milodon?  What kind of tests/research did you find out to make your decision? Also how much more efficient is the Milodon and GMB pumps over the stock pump? Are they worth upgrading to? And how does there housings match up to the stock one? Are the ports wider for more flow?

[Paul G]

FWIW I don't think you have a water circulation problem. I think you have an airflow problem. Your fan should be about halfway out of the shroud for maximum effect, so a spacer may help a little. Does your fan clutch pass the criteria in the links I posted?
I never heard it pick up speed as the engine reached extremely high temps idling in the garage. Nor does it start out at high speed from a cold start as they say it should. On top of that, an old timer I was talking Mopar and over heating issues with at a car show last summer felt that my clutch should have had a bit more resistance to turning by hand.

Try letting it sit and get hot, then put a kitchen fan in front of the radiator to see if that by itself lowers the temperature. Is your radiator properly sealed to prevent hot air recirculating from the engine compartment? Stuff some towels/cardboard around the edges where air might come back around front while stationary.
I added an electric pusher fan in front of the A/C coil. It comes on with the A/C, or by a toggle switch. It does more to keep the A/C cool at idle than cool down the motor. Well worth the effort just for the A/C advantage. It did make a small difference at cooling the motor idling in the garage.

I have to admit that I know little about the construction of small-block water pumps but it appears that yours has room for a larger diameter impeller? I don't remember what the block side looks like. After a lot of noggin-thumping I bought a GMB for my Big Block.

If you have a circulation problem, you should be able to prove that by revving the engine in neutral when hot and see the temp drop.

More to consider is how hot and clean your A/C condenser is. If your system is hotter than optimum, you're adding heat to the radiator. ditto with the transmission-do you have a loose converter? Trans heat also translates directly into coolant temperature if you have an internal cooler in the radiator.
The A/C is a new install. My old converter was toast. No stahl and vibrating badly. Changed it out for a TCI 11" at the end of the summer, also installed a small aux tranny cooler. Summer heat had passed by then.

As others have said, ignition timing can affect temps too-if you're too retarded at idle, you pass combustion into the exhaust ports which is picked up by the coolant-which may get better with RPM as both airflow and timing increase. 

Always interested to know the root cause.

[greenpigs]

I have heard both sides on wp & went with a GMB stock aluminum replacement pump. If I had a higher HP level to keep cool it would make sense to get the high volume pump, but I am going with GMB. If I am lucky I might have 325 HP to keep cool. As elacruze stated having a proper amount of the fan in the shroud is important as well.

[Paul G]

I am going to drop by Napa today and have them pull a stock pump and fan clutch off the shelf to compare to mine. I need an intake gasket set from them anyway.

[elacruze]

Elacruze I been wanting to ask you what made you go with the GMB pump over the Milodon?  What kind of tests/research did you find out to make your decision? Also how much more efficient is the Milodon and GMB pumps over the stock pump? Are they worth upgrading to? And how does there housings match up to the stock one? Are the ports wider for more flow?

I'll keep this threadjack to a minimum since it's a different engine. I'll update my water pump decision in my engine thread later, after taking some photos. Read this, if you haven't;
http://www.dodgecharger.com/forum/index.php/topic,60599.175.html
One member with a motorhome did some extensive testing on BB pumps, and the results are interesting. Suffice here to say that I went with the GMB because I believe it best fit my cooling strategy (100% at low speeds, with no consideration for high RPM power loss, and $$/warranty as second consideration).