another 440 cooling topic....

[dutch]

my 440 runs a very steady 190` while driving, but at idle it creeps up slowly and won`t stop rising. I shut it down after 7-8 minutes at 225`.
 
-440 little warmed over. Headers
-727 with seperate cooler only.
-timing at idle 12`
-emissions checked perfect at idle.
-new 440 source stock replacement waterpump. Original cast iron housing.
-180`thermostat, new and checked before installation. Has a small hole in the lip to release air.
-new fanclutch and Original 7 blade fan.
-new 26" alu radiator 2 row. new 16 lbs cap. aftermarket overflow bottle.
-fanshroud ,Original made to fit this rad.
-100% coolant. the red long life stuff. ( from Porsche so I guess that would be fine)

Last season I purchased the rad from the local moparshop and they told me it would be a good replacement since his friend had a 700+ hp 511 indy engine using the same one with no problems. I asked him what his thoughts were on my issue and he advised to purchase a flex fan ( solid mounted) and a lower temp thermostat but I`m not so sure if that`s the way to go...? any thoughts?  I`m thinking the rad may hold not enough coolant causing it to run through too fast and not cooling enough.  I don`t want to spend hundreds on another radiator unless I`m 100% sure that will solve the problem.
The fanclutch is set at exactly 1" from the rad core. The fan was not very far, maybe 20% inside the shroud so I added a plastic ring and it`s in about 90% now, but no real difference ,other than it takes a little longer to rise the temp, just a little.
So... anyone having an opinion on rad size , flexfan or anything I may have missed?  I hate to spend my summer looking at the damn temp gauge..... (which is also brandnew btw)

[HP_Cuda]

Dump the 440 source waterpump as I bought one as well and had to get a Milodon one. Big Difference!

Here is the difference:

Milodon is shown in the first pic and the 440 source in the second.

The Milodon pump will move alot more coolant than the 440 source which explains why at stop and go traffic your car goes up to 225.

B

[jhaag]

no on the flex fan, they don't work. no on lower thermostat, just regulate temp, wide open at 180, a 160 will not help your problem. pump may be part of the problem as HP said. I think your radiator is suspect. I don't think a 2 row is big enough for your application. I would also run a 50/50 mix for your coolant with some water wetter.

are you running stock pulleys? if you underdrive the wp, it will not cool as efficeintly.

[Strawdawg]

If the radiator is a crossflow design, then two tubes should work well as the tubes are probably at least 1" wide and may be a bit more.

I am not sure what percentage Porsche coolant is with regard to water but I would try a conventional coolant of no more than 50% mix.  The lower the percentage the better.  Nothing beats 100% water as long as it has a decent lubricant/surfactant package added.  If you don't have a good additive like RMI-25 or the one from Purple Ice, then run 20% coolant during the warm weather in order to get some lubricant to the pump seal and an additive as mentioned will improve the heat transfer.  This is usually good for about ten degrees of temp drop.

Say no to flex fans.  The fan should be about 0.75-1.00 from the core with about 75% of the blade inside the shroud.  Doubt this is your problem.

I am guessing that the first suggestion in the thread is the best, tho...get a better water pump that flows better.

As also mentioned, underdrive pulleys are bad for low speed cooling.

I doubt your radiator has a cooler inside the radiator so that would not be a potential problem

BTW, someone always mentions that maybe the water is flowing too fast and thus not allowing the heat to be removed-that is not correct.  If the water flows twice as fast, it gets back to the radiator twice as fast so the heat removal is the same....   Also, the faster flowing water creates more turbulence in the radiator tubes which is good for heat transfer.    Finally, the faster flow in the block maintains a more stable temp in the water jacket minimizing hot spots and potential detonation. 

[dutch]

thanks for the replies.  Steve, your theory on flow totally makes sense. and yes the rad is a crossflow and the rad block is little over 2" thick.  I`m using stock pulleys.
As for the coolant, I wonder if it`s my lack of tech english or difference in cooling liquids USA vs EU    As far as I know we have anti-freeze ( needs to be mixed with water) ,and coolant ( used pure only ) Are you saying I need to use anti-freeze mixed with water or..?  I worked at a Porsche dealership so I bought it there, assuming they use top notch coolant. crazy expensive stuff too 
As for the waterpump.... stupid thing is ,  I did order the milodon HV pump, but the shop overhere had it in backorder so the delivered the 440 source... I wasn`t happy with that but they assured me it would work just fine so I bolted it on anyways since I wanted to drive and had no clue how long it would take to get the Milodon.....   
So now I have the shop advising me to purchase a flexfan and I have to tell them they are wrong and they sold me a crap pump... 

Bryan; did you have the same problems with the 440 source pump? 
thanks guys, different pump looks like a good start then....

[Strawdawg]

I think your English is fine.  We tend to label whatever is in the radiator block as coolant whether it is pure water, or a mixture of anti-freeze and water.  We can buy a straight antifreeze and mix it with water, or we can buy a pre-mixed solution that is poured straight into the radiator without need of additional water.

With regard to the Porsche coolant, I am not sure what it is composed of-either chemically, or solution-wise.  New cars tend to run much hotter than older cars because it is good for emissions.

Sticking to the American glycols that are mixed with water at some point, the higher the percentage, the lower the freeze point which is good, but the higher percentage also raises the boiling point which sounds good but it also reduces the amount of heat that can be removed when heat is transferred to the water from the water jacket in the block and heads.  Pure water transfers the most heat but boils at a lower temperature whereas the glycols lowers the freezing point and raises the boiling point beyond that created by the pressurized radiator cap.  All those words to say it is a juggling act

The thermostat serves as a restriction which greatly increases the pressure within the block and heads.  If we think about it, we may have a coolant mix that boils at 275 degs when using a pressurized cooling system BUT the temperature in the heads may be much higher as combustion temperature might be a 1000 degs F or more.  The thermostat when combined with a good high volume pump may create a inside the water jacket of more like 50 psi which makes it hard for a hot spot to produce steam.  Steam in the cooling system does not transfer much heat. 

Think about a water pipe with your thumb over the end...you can feel the pressure increase behind your thumb as you reduce the opening size.

Anyway, I digressed, as usual, What I was trying to say is that I don't know how the Porsche coolant compares with what we use over here and if it has a high percentage mix to water, it may be quite inefficient when it comes to heat transfer...either out of the engine or into the radiator core....

If you can try pure water with an additive to keep the pump lubed, then you will find out what the difference might be....

The 440 has had restricted flow for some and others have reported no problem...From what I have read, I would not use one myself altho I would hope they have addressed the problem.

[dutch]

clear 
with that said,  what you think of a 180 stat and a more or less steady cruising temp of 195?  My feeling says it shouldn`t be that much over 180...?  Also ,Idling with the hood opened makes the temp drop a bit, but it will still stay at 212/215.  The 440 idles at 950 in neutral. In drive at 750 the temp will rise a lot faster.
I understand it takes a little time to get the temp down when it opens, but a thermostat is actually a temp limiter, right? and at 195 it is open all the time, so while cruising it already is too hot actually? 
I guess I`ll start with getting another pump and changing coolant to a 50% anti- freeze/ water mixture and see what happens then. While at it I will trim the shroud to have the fan in 75% too.

[Strawdawg]

clear 
with that said,  what you think of a 180 stat and a more or less steady cruising temp of 195?  My feeling says it shouldn`t be that much over 180...?  Also ,Idling with the hood opened makes the temp drop a bit, but it will still stay at 212/215.  The 440 idles at 950 in neutral. In drive at 750 the temp will rise a lot faster.
I understand it takes a little time to get the temp down when it opens, but a thermostat is actually a temp limiter, right? and at 195 it is open all the time, so while cruising it already is too hot actually? 
I guess I`ll start with getting another pump and changing coolant to a 50% anti- freeze/ water mixture and see what happens then. While at it I will trim the shroud to have the fan in 75% too.

If it were 38 degs C outside when it was running 195, then I would say it was normal but I am pretty sure that your temps are not in that range at the moment.  If it is running that warm going down the road, then it could be the pump not moving enuf coolant thru the system.  At a reasonable highway speed, it would not an airflow problem.

Opening the hood allows the trapped air under the hood to escape and this air is very hot.  Some say to remove the cowl seal from the radiator but this does no good while the car is moving as this is a  high pressure area...if anything, it will push the underhood fumes into the vent system.  It may help while the car is sitting still and there is no built up air pressure at the back of the hood so that can can move thru.  Normally, when moving, the air should move under the car and be sucked out.

Why don't you just drain the coolant out of the radiator into a pail and refill with bottled water?....this will remove about half the coolant.  Drive the car and see what the temp does.

I have a 22" aluminum two row radiator and my car runs about 190 on a 38 C day at 75 mph-guess that is about 120 kph.

If you were a Brit, I would say you had a left hand drive radiator in a a right hand car, but...   

[dutch]

 

hm...not even sure if the coolant mixes with water... I`ll look into that.
Not a lot of highway driving for me. Running 4.10s in the rear, most miles are done between 30 and 60 mph.
We had 68`outside today. Mid summers max about 86-93.  that scares me ... car -wise 
Thanks man, I learned a lot tonight 

[Strawdawg]

then you are turning a lot of rpm and not making much speed to match up so the engine is working harder and the air flow is not as good as one would like...that is not helping anything!   the fun factor is great tho!

[cudabob496]

see if problem goes away or is minimized if you increase your idle rpms

[dutch]

then you are turning a lot of rpm and not making much speed to match up so the engine is working harder and the air flow is not as good as one would like...that is not helping anything!   the fun factor is great tho!

jup...I know, and yes it is 

see if problem goes away or is minimized if you increase your idle rpms

cranked it up to 1200 ,didn`t make any difference 

[Strawdawg]

Is your clutch fan the thermal type of clutch?

[dutch]

yes

[Strawdawg]

The problem is made worse because you are running higher rpm at lower speed so the engine is displacing heat into the coolant more rapidly while the car is not always moving fast enough to get a high rate of air flow across the radiator core.  It's further complicated because a clutch fan is designed to decouple as the rpm comes up which is normally good because vehicle speed is enough to provide offsetting air flow.  The thermal clutch is intended to look at the air temp coming thru the core and "tighten" up but that is probably somewhat of a variable depending upon the clutch in question,.

A flex fan flattens out with increasing rpm and acts like a clutch fan so it is not a solution.

The cheaper electric fans like Black Magic and Flexlite appear to have good airflow ratings but they fall on their faces when put up against a radiator core because the motors are weak as evidenced by the lack of amperage pull.  The good aftermarket fans like Spal cost a lot of money for an experiment   If you lived a bit closer, I would pull a pair off one of my Buicks and see they would do on your car....the best buys over here are usually ones off a serious performance factory car so I wonder if Merc or one of the other high hp cars over there have a fan/fans that would drop in...most of them will take a good alternator for long term usage due to the current pull.  Know anyone with a good set of fans that you can borrow?  The chevy HHR fan was popular here a while back..but I think the Lincoln and Taurus SHO units are stronger.

The 440 Source pump problem was due to a restricted coolant passage as I recall.  Someone in the past posted a picture showing how small the passage was on the problem pump.

The coolant is an unknown.  Generally, straight water is the most effective coolant as we said and that is probably the easiest thing to try....

I hate to tell someone to spend money in hopes of fixing a problem like this.   One of the northern Canadians running 4.10's might have some valid info as to expected operating temps if we could find one to hold the speed way down

Is this an automatic tranny?  If so, I am assuming you are not routing the tranny fluid thru the radiator but are using an external cooler instead of one that is the radiator tank.