6.5 over heating

[dbrannon79]

as long as the screws or bolts you used to lock up the old clutch won't shear off and allow the fan to freewheel again, it should last a few weeks or until you can get it all replaced.

as for the pump, order from @RockAutoLLC and get the Ac Delco pump for a 2000 6.5. if you go the electric fan clutch, order from the same place and look up the AC Delco one for a 2010 express van with a 6.6 d-max. use the plastic d-max fan blade for the same 2010 express van. iirc 2011 uses the same too. and then get the Hayden fan controller. there are three different styles you can use, each one is the same but with a different temp sensor. one with a stick in probe for the radiator, one with a 1/4" pipe thread and another with 1/8" pipe thread.

I got the one with the probe and strapped the probe to the back side of the t-stat crossover so I can use the port in the passenger head for a manual tamp gauge.

be sure to use the 5% discount code posted here in the vendor section from Rockauto.

 

[Will L.]

Only thing the screw through the fanclutch hurts is obviously a death nail to the clutch itself- and your mpg will drop a little. Might have to turn up Charlie Daniels a little more to hear over the noise- but any excuse to do that is a good one.

 

[smokymtn65]

I used to the one with 1/8 npt, and drilled and tapped the crossover , works good for me.

 

[DieselAmateur]

Glad it showed improved results! As far as I know the only downside to keeping the fan locked 100% of the time is it will decrease fuel mileage as others have mentioned

For the electric fan clutch you won't use a steel fan, you have to use a fan that matches the electro viscous fan clutch

When you got the SS Diesel cooling upgrade kit did that come with a new water pump? If not the AC Delco part number you want is

251-603​

Read through the electric fan clutch thread for part numbers and instructions, I have all the parts just yet to find the time for the upgrade

Electric Fan clutch

So for those who want accurate fan clutch engagement this could be for you. I know on my 96 the fan clutch has never engaged the entire time I've owned it. Living in cooler climates does have it's advantages. I even tried modding the spring to no avail. This clutch will only work with the spin...

www.thetruckstop.us

 

[MrMarty51]

All of this hot weather, got a fully functional cooling system on the truck and here I set and lay around, I dont think it would be a good idea to go out driving around with just a couple of flimsy stainless steel screws holding me together.

 

[Husker6.5]

So, @MrMarty51, get that roll of duct tape and wrap yourself up! Look, the mummy!

 

[Stoney]

I did the upgrade to the high flow pump and spin on fan, hell I even have twin 170 degree thermostats to open lower and in this heat she's still been running at 200. Hit 210 tonight pulling a small hill. Need to flush it out and clean the cooling stack again I guess..
Side note. Since we're talking about trucks and cooling systems these trucks are supposed to have Dex Cool antifreeze.. according to the sticker.
I've heard both ways on this. Do y'all think the Dex Cool actually does anything or should you just run the green bug juice.

 

[93detroit]

Stoney, something has to be unhappy in there. I have the same w.pump you do with a Duramax fan and a 180deg single thermostat. My truck will run up to about 180ish before the thermostat opens, and then will usually run about 170ish even at 95degrees outside with the a/c on. Towing stupid amounts of weight up mountains with the water/meth on it will hold a steady 190 (one full line below the 210 mark). If you posted what radiator you have, I don't remember at the moment! Make sure she's not plugged up.

 

[MrMarty51]

Green bug juice in my 2000 and it seems to like that.

 

[Will L.]

Green prestone sheds more heat than dexcool.

 

[Husker6.5]

@Stoney Flush and clean the cooling system chemically, check your cooling stack and clean it, too. Refill it with a 60/40 mix of ethylene glycol (GREEN) antifreeze/water and two bottles of Water Wetter. It's what I've always ran in both of my 6.5s, my 98 Burb and my 94 HD 2500 C&C.

 

[jrsavoie]

Yeah, it seems that when I mention that test procedure, I forget to also me tion tnat it will destroy that fan clutch.
I was fortunate that I had the old spin on fan clutch from My truck that had already failed and so I used that for the test. I also have the almost brand new spin on fan clutch from Kennedy Diesel and it was a failure right out of the box. It is too bad that the warranty had expired on it before I got a good chance to test it out.
If anyone wants a spin on fan clutch for a test procedure PM me and I will send You one that is already setup and ready to go. Just add Your fan and spin it on. No return is necessary.
I also discovered, after running the test fan clutch for several thousand miles, that gooey waxey stuff sort of splatters and gets on stuff. When I recently pulled the top shroud and fan from My truck, I thought, what in the world has been leaking, poked My finger into the stuff and discovered it was quite goopey. Okay, now I know what that is. cleaned it up with a little solvent and some B&P cleaner and good to go. No more dirt or dust will collect on that area.

@Stoney Flush and clean the cooling system chemically, check your cooling stack and clean it, too. Refill it with a 60/40 mix of ethylene glycol (GREEN) antifreeze/water and two bottles of Water Wetter. It's what I've always ran in both of my 6.5s, my 98 Burb and my 94 HD 2500 C&C.

We also use distilled water.

 

[Stoney]

@Husker6.5 what do you mean chemical flush

 

[dbrannon79]

@Stoney I always pull the stats out and run the water hose at full blast through everything till it's clear. when I flushed my rig (first time) I had to dismantle everything including pulling out the coolant bottle up on the fire wall because running water didn't get it all. I had some VERY nasty crap come out of that bottle. the radiator I had sent to the radiator shop months prior to have the plastic tank replaced so it was ok, but for you, it probably will need to be pulled and cleaned inside and out. most shops don't charge very much to pull one of the tanks and rod it out for you. you'll never get all the junk out just by running water through it.

hell I have a drivers side replacement tank if someone needs it. ordered it and didn't need it since the shop had one in stock.

 

[Will L.]

I would not spend a penny on anything until the fuel bug situation is done.

Chemical means there is a chemical you buy at the parts store made fore breaking up the build up inside the radiator and engine.

I always do a water flush like Said above first- then so the chemical.

 

[Husker6.5]

@Husker6.5 what do you mean chemical flush

I mean exactly that. Like using Prestone's cooling system flush treatment or something similar that will dissolve any scale build up or sludge/gunk in the cooling system - especially in the block/heads and in the radiator/heater core, after first backflushing the system out using a garden hose. Also, don't forget to drain out the block by removing the pipe plugs on each side while backflushing to get all antifreze out of the block - as well as any gunk/sludge/casting sand that may be in there, then reinstalling them before doing the treatment. Remove them to ensure that you have all chemical flushed out of the block, then fill up the cooling system with a 60/40 mix of ethylene glycol (green) antifreeze and distilled water.

Taking your radiator into a radiator shop, having them pull the tanks and boiling out the core, if cheaper than buying a new radiator, wouldn't be a bad alternative to chemically cleaning the system to get any calcium (scale) deposits, gunk/sludge out of your radiator, either.

 

[Big T]

I did the upgrade to the high flow pump and spin on fan, hell I even have twin 170 degree thermostats to open lower and in this heat she's still been running at 200. Hit 210 tonight pulling a small hill. Need to flush it out and clean the cooling stack again I guess..
Side note. Since we're talking about trucks and cooling systems these trucks are supposed to have Dex Cool antifreeze.. according to the sticker.
I've heard both ways on this. Do y'all think the Dex Cool actually does anything or should you just run the green bug juice.

Same issue on my son's 1994 Suburban. All the mods, but 190 t-stat. It quickly runs up to 190 and will hit 200 on flat level ground in the summer. Tow something uphill and it quickly goes to 210. Some of it might be the dash gauge as I noticed it was 5 degrees higher that what the GMTD Scantech was reading.

 

[Will L.]

Two locations, head and crossover. Even with identical gauges you can get different reading there. Factory gauge in dash is notoriously off.
I always recommend a decent mechanical gauge tapped right rear head for reference.

If he can’t make improvements to the cooling system at the moment, he needs to keep mr happy foot in control by that temp gauge. Remember the guy behind you honking doesn’t pay for the new engine. At 210 he is on the edge.
200 good
210 watch the gauge more than the road 220 immediately pull over and let it idle to normal temp.

 

[snarl95]

How about water wetter?

 

[Big T]

How about water wetter?

My experience with water wetter: it does nothing.