keeping the 6.5 cool

[stephen]

I am getting ready to put a new engine in my 95 suburban. I want to keep this one cool thinking of the dual themastate set up with the upgraded ho pump. my question is this should i go with clutch fan or flex fan? I had a bad cluthch fan on the old engine burned it up. Im leaning towards the flex fan .Any input would be greatly appreciated. tHANKS IN ADVANCE

STEPHEN:grouphug::mad2:

 

[ak diesel driver]

go with the 9 blade fan and the heavy duty low temp fan clutch or do the fan clutch mod

 

[Brooklyn Tow]

D=Max fan is night and day, compared to the 9 blade 20" steel.....trust me.

 

[bk95td]

The 9 blade fans are cheap in the junkyards. I've seen them for $20 on car-part.com. I don't think the dual stats do much. The thermostat[acdelco only] radiator and fan clutch seem to be the most important components. The rad needs to be taken out and cleaned on a regular basis[at least every 2 years]. You need to take the tranny and engine oil coolers loose and clean behind them along with the condenser.The HO pump helps some. The a/c didn't work on a couple of my trucks so I took the condenser out.
Anything that can lower exhaust temps will make the engine run cooler also. Free flowing exhaust,better air filter, more effecient turbo and water mist injection.

 

[WarWagon]

go with the 9 blade fan and the heavy duty low temp fan clutch or do the fan clutch mod

I have this 9 blade low temp clutch setup and it keeps the temps below critical. HO water pump and 180 T-stat too. A original 15 plus year old fan clutch that wasn't working also set my engine up for death by scuffing a piston.

Cleaning or replacing the radiator and condenser by unbolting the oil cooler to get at the mat behind it and pulling the radiator from the truck for cleaning can not be emphasized enough.

A dual thermostat is not necessary. HO pump is all you should do as this helps an uneven block water flow issue. The real problem is airflow or lack of through the radiator. Plugged/not enough fan soon enough etc.

A Dmax fan I am sure can be better. Airflow through the radiator is the problem with our trucks. However my sig setup works pulling a trailer WOT for extended grades.

A flex fan is noisy and I doubt will pull enough air at idle. The flex fan I put on my gas Yukon sucked power and allowed the AC to warm up some at idle. They can also wall off airflow at speed by going flat and blocking any airflow.

The low temp fan clutch runs enough to drive some batty - but it does the job and keeps her cool. Power and fuel economy are 2nd to that... At WOT with the AC on the only way the temp gauge went was down when the clutch locked up. But you have to have clean radiator/condenser for this to be true.

 

[Burning oil]

IMO: do the maintenance like Barry said, get the Dmax fan as Luis said, HO pump WW refered.
If you do all that then also go with 195 Tstat you can increase mpg over 1mpg.
I switched and got 30-45 extra miles per tank. That adds up real fast.

 

[buddy]

Is the ACdelco stat actually 190*

I prefer the single stat xover as well. If youre going to buy a new water pump, clutch and fan I would recommend you purchase the water pump and clutch for a year 2000 6.5TD.

I agree with the Dmax fan and any new clutch that you do the mod on so it kicks in just before 210 instead of after. You dont need an expensive clutch, just one that works.

Clean radiator outside AND inside, or just have a radiator shop do it, as they will give it a nice bath. Then use only distilled water with your coolant. Dont go extreme on the antifreeze, maybe just 25-33% + watter wetter if it protects it down to temps in your area. If you tow a lot in the summer you can use only a 10% antifreeze with a bottle of watter wetter.

 

[Burning oil]

Is the ACdelco stat actually 190*

.

Hey Buddy, are you saying the 195* actually opens at 190* ?
The AC Delcos I am using are 195,s

 

[buddy]

Just that RockAuto sells the ACDELCO Part # 131-91, dual spring 190* stat

ACDelco also says that
12T45D is 180* is an alternate temp
And
12T45E is the 195* that is listed as recommended

The AC Delco 131-103 for dual stats is also a 190*

So some people may be getting the 190s and others the 195s, no big deal.

 

[Acesneights1]

See, I got better results using the 9 blade with the Hayden Severe Duty clutch. In fact I'm in the process of putting one on now. Had to replace the WP cause I could'nt get the old fan off it. I think the moron Locktited it and used a monkey wrench to tighten it. Just douched the entire thing. I have witnesses that I oulled it apart so when my "Help it's overheating " get's revived I'm clear...
Actually we had trouble getting to to heat up and it was hot today.

 

[Burning oil]

Just that RockAuto sells the ACDELCO Part # 131-91, dual spring 190* stat

ACDelco also says that
12T45D is 180* is an alternate temp
And
12T45E is the 195* that is listed as recommended

The AC Delco 131-103 for dual stats is also a 190*

So some people may be getting the 190s and others the 195s, no big deal.

Thanks buddy.

 

[handcannon]

IMO: do the maintenance like Barry said, get the Dmax fan as Luis said, HO pump WW refered.
If you do all that then also go with 195 Tstat you can increase mpg over 1mpg.
I switched and got 30-45 extra miles per tank. That adds up real fast.

Does the Dmax fan and clutch fit on the early low volume water pumps? I'm still learning what parts will interchange with what. Within the past year the P.O. of my pickup replaced the water pump and I don't want to replace a new pump unless it becomes neccessary to do so to keep towing temps down. The fan had the leading edge of one blade bent a bit after the P.O. smacked the tree. I've straightened it out for temporary use until I can find a replacement.

Here's what else I've done to the cooling system. I've found an all metal rad, out of a 95 K2500 pu, which is currently at a rad shop being tested. The single stat coolant crossover was damaged in the accident so I found a double stat crossover out of a 2000 model. The AC condenser was also damaged so I have a new one to put in. All this means the seeds and other crud between the oil cooler, AC condenser and rad will be gone. In addition, I have some window screen to cover all this to help cut pown on future crud buildup.

Anything I'm missing to get this ready to tow with this summer?

Don

 

[WarWagon]

Does the Dmax fan and clutch fit on the early low volume water pumps?

I don't want to replace a new pump. The fan had the leading edge of one blade bent a bit after the P.O. smacked the tree. I've straightened it out for temporary use until I can find a replacement.

In addition, I have some window screen to cover all this to help cut pown on future crud buildup.

Anything I'm missing to get this ready to tow with this summer?

Don

You could be missing your head if that blade breaks off the fan while you are looking under the hood! :nono: There is no temporary fix for a bent fan - it is just a grenade waiting to go off! I would stop running the truck and pull out that fan until a replacement arrives. Fans are not designed to bend and tend to crack while bending.

21" Dmax Fans interchange with the 20" steel 9 blade units. The 21" may have clearance problems with the shroud depending on engine mounts and how well the truck was repaired. the 6 blade old fans were incompatible by bolt hole location to the fan clutch and needing 6 bolts. Fan clutches have 4 bolts or screw on. Screw on being the latest and most expensive year for parts. Aside from the junk 6 blade 6 bolt fan the fans use the same 4 bolt design - You could even run a 21" Trailblazer fan with the standard 4 bolt pattern on the fans.

The waterpumps are proven to flow more water to the driver's side of the engine. The low out water pumps make this problem worse by overheating the passenger side head while the driver's side reads fine from the gauge sensor on it. Change the pump to a HO pump. The very latest part number requiring a screw on fan clutch is said to solve this bank balance flow problem. And not all screw on HO pumps do this. However a HO pump is enough to make the problem small enough to keep you under the critical temp for cracks.

The window screen is a restriction. Yeah it would act as a filter, but, it is worse by being a restriction more than it will help. Again this body style hardly gets enough air through the radiator stack as it is. Adding a screen makes the fan run more by reducing airflow and our case can tip you to the overtemp situation. Don't do it.

 

[Matt Bachand]

D=Max fan is night and day, compared to the 9 blade 20" steel.....trust me.

Standing next to TD's truck with the dmax fan is a HUGE difference of air flow compared to stocker.

I'm going to get one just because.

As far as putting a screen over the grille? Dont' do it.

Have you ever carried a screen in the wind? IT will toss you around almost like a piece of plywood will. It will reduce airflow.

 

[Acesneights1]

If you've got the 4 botl fan ge the Kennedy. It kicks in lower. AFAIK the Heath one works with his waterpump which is the late model hub style.
Matt, Before you blow 350$ give me a few days to test what I did. That clutch was only 142$. I'm be towing in 2 weeks hopefully and will report how it works. I had to burn the old one off. BTW for future refence the fan threads on normal not reverse.

 

[Matt Bachand]

I am not replacing my clutch, just the fan... My clutch works great with the DIY mod!

 

[Matt Bachand]

Anyone know the cheapest source to buy one of these 21" fans?

Rockauto has them for 40 bux.

Any 2002 year duramax should have this stock? Or is there a specific year?

Anyone have a current rockauto discount code?

 

[Brooklyn Tow]

Like I said......Day and Night!

 

[stephen]

i realy want to thank all of you your input, i only hope i can return the favor some day. thanks again



Stephen

 

[TurboTahoe]

Heath advises to stay with a 1 stat setup. He thinks it does a better job because the design forces all hot coolant to take a trip through the radiator, the dual stat design doesn't have a way to force coolant to go to the radiator.

Don't forget the stats are totally different as well.

-Rob