Cooling System Upgrade ???

[BorJansson]

With Ref to " Heath Diesel´s 6.5L Diesel Heavy Duty Cooling System Upgrade" ( MaxxTorque Article Published Spring 2009 )

I have in mind to install water coolig pump part nr. 88894035 and keep the single single thermostat housing.
But I can´t figure out if this pump fit on a 1994 6,5l diesel w. turbo and serpentine belt ?

I live in an area with winter and summer and temp. from -25 to +30 deg.C ( -13 to 85 F ) .
Light duty running and no trailer.
What is the recommended temp. on thermostat ?

...............................................
1994 Chevrolet K-1500 Silverado

[DennisG01]

I didn't see that part number listed on Heath's site, but...

With the way you are using your truck (and the relatively mild temperatures), are you sure you need to do this modification? Maybe you just need to clean out the fins of the radiator and other coolers? Possibly pull the radiator and give it a good flush, too.

[mrwilecoyote]

It's the 99+ Spin on Hub Waterpump. I think the fan Clutch was a Hayden 2886 SD for a Duramax Kodiak. I would have to check the book. Either a 2001 Dmax fan or a 9 blade steel from a 99+ 6.5TD will bolt up to it. Some swear by the Dmax fan. I have used both and saw no real difference but would say the 9 Blade steel "sounds" like it's pulling more air. I think I have tried everything you can try in cooling mods including retrofitting a GMT400 with a Copper Brass rad from a 93. The Dual Tsat provides no benefit unless you put a restrictor in the bypass.
First step as always is to remove the rad and clean the heck out of everything. The GMT400s were a poor design for airflow. That is the main reason they run hot. The improved waterpump does not really help as far as keeping the engine cooler towing because it does not matter fast you move the water, if the Rad is not getting rid of the heat then you are only circulating hot water. The reason the newer waterpump is better is because it balances the flow to he rear of the heads to keep the heat more even in the motor and prevent cracking. Before GM came out with the improved waterpump, Heath had a Bypass kit he used to sell that used the two rear block off plates on the heads and a return to the T stat housing to balance the flow but the 99+ Waterpump makes that unnecessary
I now run what in effect you could call a 6.5 setup in my old Squarebody.
I'm running the GM4 the "choking" turbo and I have run hard on the highway towing and I CANNOT get that truck over 200 and the egts so far have not passed 1,000 but the old K30's have way better airflow plus no oil cooler or a/c condenser blocking air. I have worked on a 94 K3500 that tows regularly with the stock GM cooling system and has never ran hot but the truck has no a/c.
In theory over 20 mph you should not need an engine fan at all but in reality the fan comes on with these rucks to "pull" the air through the stack of crap GM piled on.

[mrwilecoyote]

As far as thermostat the single system should have GM AC delco stat only. It blocks the bypass. Use of aftermarket will allow coolant to bypass the rad.

[mrwilecoyote]

Also be careful when buying aftermarket waterpumps. Most of the stuff is made in China junk. Here's some pics of one I bought from Advance Auto that did not line up with the timing cover....I ended up returning it and using a spare used one I had from my Dually. Note the differences.

[Kennedy]

There is no need to do the 1999+ style water pump. Only the hub was changed and that change was an assembly line speed/cost cutting improvement. There is no such thing as a Hayden fan clutch with anything other than factory stock calibration. The calibrations have been moved UP with each seties which is the wrong direction. The afformentioned bypass kit was debunked some time ago as being a pure crock of BS as is the balanced flow water pump. Yes there are still vendors out there that are full of it.

My recommendation is to do the high capacity water pump and dual stat setup but stick with the 4 stud water pump. The idea is to move more water through the engine picking up the localized hot spots caused by poor flow. The duel stat setup is necessary to provide additional outflow area during high RPM operation. For a cool climate I'd recommend the OE stats as providing the best heater output, primarily in low speed operation.


Your choice on clutches for your climate. I won't push mine for a cool climate but it's still a good idea. The 1997+ 9 wing steel blade is the best blade choice.

[BorJansson]

The rradiator(s) will be cleaned, in and outside.
I have owned this truk for abt. a year. Only easy driving, no towing. 160k miles on meter.
Past history I have no idea about.
During my time it has not been driving hot, abt. 170 - 180 F.
Then suddenly one evening temp raised to abt. 220 F and pressed out coolingwater
When I took the engine apart and examined the heads we foud cracks between valveseats in cyl. 1, 5, 7 and 2, 6, 8. Several cracks go also trough the seat. I guess the heads are junk.

It must have been runned hot sometime and I want to avoid it in the future.

............................................
1994 Chevrolet k-1500 Silverado

[Kennedy]

The valve seat area cracking can happen on a truck that is not overheated also. The localized hot spots and poor overall flow are to blame more than anything.

As for the radiator, if it was running Dex Cool it will likley look like new inside.

[mrwilecoyote]

There is no need to do the 1999+ style water pump. Only the hub was changed and that change was an assembly line speed/cost cutting improvement. There is no such thing as a Hayden fan clutch with anything other than factory stock calibration. The calibrations have been moved UP with each seties which is the wrong direction. The afformentioned bypass kit was debunked some time ago as being a pure crock of BS as is the balanced flow water pump. Yes there are still vendors out there that are full of it.

My recommendation is to do the high capacity water pump and dual stat setup but stick with the 4 stud water pump. The idea is to move more water through the engine picking up the localized hot spots caused by poor flow. The duel stat setup is necessary to provide additional outflow area during high RPM operation. For a cool climate I'd recommend the OE stats as providing the best heater output, primarily in low speed operation.


Your choice on clutches for your climate. I won't push mine for a cool climate but it's still a good idea. The 1997+ 9 wing steel blade is the best blade choice.

He has a 94. Even the 4 stud was upgraded in later years so I disagree about putting a newer water pump on. I also disagree about the bypass mod. I did it and noticed a difference. it's obvious if you look at the dual housing that there is nothing to block the bypass like the earlier single stat housing. This has nothing to do with vendors, I made my own bypass with a 1/2NPT tap and a 50cent pipe plug with a hole drilled in it.
Also Hayden makes a severe Duty fan clutch that has a better lockup than stock. I would post the book but the file size is too large.
I have owned e very variation of the 6.x cooling system personally and tried every variation of mods including your special calibration clutch.
In fact it's in the classifieds for sale right now as I no longer own a truck with a 4 stud WP. It worked fine but I now run a spin on.
I think the 9 blade works better too but not much and the Dmax fan blade is much cheaper.

[Kennedy]

The bypass cooling was debunked long ago. http://www.thedieselpageforums.com/t...ad.php?t=25230


The Hayden clutch is nothing more than a OE clutch with OE spec in a Hayden box.


The HO water pump is the HO water pump. The fan clutch attachment is merely a production line upgrade. Spin the clutch on and no more studs, nuts, lock washers and poor access to tighten.


There is no need to block off the bypass port of the stat housing. This port was always there and only blocked from 92-95 and never again. The 1997+ truck ran cooler with more uniform temps and much less chance of cracking the heads unless severely overheated where the prior models cracked even with soccer mom duties.

[mrwilecoyote]

The bypass cooling was debunked long ago. http://www.thedieselpageforums.com/t...ad.php?t=25230





The HO water pump is the HO water pump. The fan clutch attachment is merely a production line upgrade. Spin the clutch on and no more studs, nuts, lock washers and poor access to tighten.



.

yes, and he has a 94. Not the HO. I am still looking for the Hayden book.
The Clutch I used was not a 6.5TD Clutch.

[Kennedy]

The Clutch I used was not a 6.5TD Clutch.

The Dmax has a large air-air cooler up front and comes with an even higher engage temp than any 6.5 ever did. The later model clutches were cept up even higher so that now most every model year Dmax has been shown to overheat in extreme conditions. Some less extreme than others.



The old tried and true (written in the 1998 volumes as I recall) cooling upgrades using the HO water pump and the dual stat setup is still the best alternative. We have supported this for many years now by offering as a complete kit. Unfortunately there are some that want to push the screw on style hub as a better option which it is not and it disallows the use of the KD clutch. The KD clutch is the only one with a lower than factory spec engage temp. .

[mrwilecoyote]

I never said any of these clutches engage sooner or later only that they were severe duty which means they have a better lock up ratio than stock.
Here is the Hayden catalog. As you can see they make a few different models.
Standard Duty, Heavy Duty and severe duty. The differences are explained clearly in the catalog.
http://www.haydenauto.com/upload/Hay...fan-clutch.pdf
I had to post the link because it was too large to upload. Hayden is not a vendor they are a manufacturer and this is a spec catalog not a price so I believe this link to be in the forum rules as you yourself sell Hayden.
For the record I have never used head bypass setup but I did see it personally on Turbine Doc's truck. AFAIK he still runs it.
Also I went with the Spin on this time around because I had the WP off a 6.5 that handgrenaded and it was a GM factory Pump which costs well over 250$ for a quality one and it was cheaper to buy a 2886 Hayden than a new waterpump to use your clutch. Hence the reason I am selling it.
I used your Clutch on my 98 with a Steel 9 blade.

[Kennedy]

Hayden does make some fan clutches but not the diesel ones for the GM trucks. They repackage the OE clutches and call them their own. Stock calibrations, stock engaged speeds, just plain stock.

What happens here is some guy reads a thread like this thread, sees the recommendation that he needs the screw on style and a Dmax clutch then he goes out to tow and finds that the calibration is all wrong. Then I get to spend 1/2 hr plus or better explaining to him but in the end he probably can't justify spending the money to redo something that he just spent a bundle on.

I'm a pro-OEM type of guy in most cases, but the water pumps have gotten too expensive from GM so we've been doing aftermarket for years now. I have yet to have a warranty failure claim mor a legitimate not fit claim.

[mrwilecoyote]

I'm running a Hayden 2886, Dmax fan and the spin on WP. I have no overheating while towing problems and I'm running a small turbo and turned up IP. I'm turning 35's to boot so to say using a Hayden SD clutch is gonna cause overheating and that it won't engage right is wrong.
Either the 4 bolt or spin on HO WP with either fan and a Hayden clutch will make a big improvement over the older cooling system >97.
Aftermarket Water pumps are a crap shoot which is why I posted my pics so anyone reading this thread would check becuase it's easy not to notice how badly they may line up.

http://www.youtube.com/watch?v=1h_17...6rEUlfnbrRy3Iw
Two quads, Spare tire, Trailer, 100 gal of diesel in a transfer tank(cheaper in PA) Spare NV4500 and probably enough tools and parts to rebuild the entire truck. Was on my way back from PA. Speedo is off by 5mph. It was doing 70 . Pyro at 1,000 on acceleration and ECT 195. Pulled some big hills though upstate NY. No issues.

[greatwhite]

There is no need to do the 1999+ style water pump. Only the hub was changed and that change was an assembly line speed/cost cutting improvement. There is no such thing as a Hayden fan clutch with anything other than factory stock calibration. The calibrations have been moved UP with each seties which is the wrong direction. The afformentioned bypass kit was debunked some time ago as being a pure crock of BS as is the balanced flow water pump. Yes there are still vendors out there that are full of it.

My recommendation is to do the high capacity water pump and dual stat setup but stick with the 4 stud water pump. The idea is to move more water through the engine picking up the localized hot spots caused by poor flow. The duel stat setup is necessary to provide additional outflow area during high RPM operation. For a cool climate I'd recommend the OE stats as providing the best heater output, primarily in low speed operation.


Your choice on clutches for your climate. I won't push mine for a cool climate but it's still a good idea. The 1997+ 9 wing steel blade is the best blade choice.

Good advice.

[dixiepc]

So what's the deal with Evans coolant. They say that you can run higher temps. I can't find any thermostats that are hotter than 192 degrees. Is it even advisable to run at these higher temps.

[sctrailrider]

So what's the deal with Evans coolant. They say that you can run higher temps. I can't find any thermostats that are hotter than 192 degrees. Is it even advisable to run at these higher temps.

I run the Evans coolant in my 6.5, I don't run it to be able to run a higher temp, I run it because when towing things will tend to heat up more in these motors, the Evans doesn't boil and cause hot spots inside the heads like water base coolant does, there by the coolant stays in contact with the metal and doesn't form steam pockets/ heat spots. I also don't have a pressurized system either.