210 hot or NOT?

[orrum]

There u go Nobby I agree completely with u and thanks!

 

[jrsavoie]

I ordered a 195 degree high flow Stewart thernostat part number 306 for my single stat applications and have had good luck with it. My 89 always ran 8900 GVW or more and I never had a temperature problem
EMP Stewart Components
2900 27th Avenue
Escanaba, MI 49829
Telephone: (906) 789-2816
Fax: (906) 789-7825

 

[Crankme69]

Thanks Jeff maybe I'll try one.

I am almost sorry I started this post, 1st I got smart ass comments back from Big T that helped NO one nothing.

Big T is correct on one aspect yes I am complaining about the abilities of the 6.5 truck. I pulled this very same trailer years ago with got dam S-10 blazer with a friggin 2.8 liter V-6 without any cooling issues & yes I could run the AC.

I realize my truck is old & prolly worn out but my expectations were not met & all I wanted to do was share my frustration & maybe just maybe provide someone with some insight to avoid a similar incident.

I have used this trailer since the early 90's & have pulled it with many gas vehicles NONE of them acted like this 6.5 did. So yes I am complaining & I am not going to feel bad about the 6.5 short comings & my actual experience.

I like the 6.5 parts are cheap BUT it leaves much to be desired...SORRY Big T & anyone else that needs thicker skin!

 

[buddy]

At this point the truck didnt really get too hot, its just the false fear everyone has been programmed to have. Per GM you were nowhere near the hot line, and in all the other vehicles you likely trusted the gauge for what was hot. I just dont think you have to worry at all about sitting at 210F on an entire cross country ride, and short stints there are common until the fan kicks in, we just got to get the fan to kick in like it did on other vehicles.

And the 6 blade fan and clutch should be replaced, if not the water pump too, because they are a recognized deficiency for towing. The free fan mod would likely do you just fine for lesser towing challenges.

Like Orrum said, he drove one loaded heavy and didnt know any better about the ECTs or EGTs and it made it. I would be willing to bet he was over 210F a good amount of time and it was nothing to worry about for him because the red are isnt until much higher. Although we know better now not to run them hot, shouldn't be paranoid about 210F. I have more faith in them than that.

 

[iamdave0887]

The only thing i find interesting is that the older 6.2 bodied trucks the temp gauge was special for the diesel engine(as was the oil pressure gauge). It went 100-200-240, with 200 being in the center and the red starting just before 240. Gasser trucks were a totally different gauge.

with the GMT-400 series the gauges are all the same. Guess GM found another way to save some pennies.

I'd agree with the 6.2 gauge with the red zone starting at ~230-235*F and the gauge maxing at 240*F, before i agree with the 6.5 gauge's red zone at over 250*F.

 

[jrsavoie]

I still want ot do something with my International. It should have a lot of miles left in it. Just have to figure out a way to make it a 4x4 daily driver

 

[orrum]

Here we go again, I have a 6.2 and the temp gauge has 210 on it not 200 and the red line is way up there, gonna have to go look.


Buddy u r right I have no idea what the temp was on Bobs 6.5 turbo but I know it was no where near the red, I would have panicked and called him afraid I was gonna blow it up! I must point out it was Feb. and not July with 100 degrees in the shade.

 

[nobby]

Crank, mine and Orrum/others comments do not negate your want to get your truck cooling properly or to that matter improve your own personal comfort zone. We can pontificate all day about what numbers are safe etc but the truth is the more in check you keep those numbers the better life your engine gets.

Personally I do not get freaked out by an engine at 210 or thereabouts when under a heavily loaded condition it kind of goes with the territory. For me gauge reading often is more about changes then absolute numbers. I.e when under load does it get to 210 and plateau or keep rising. Nothing more frustrating than somebody giving a 2nd engineer absolute numbers who then come wakes you because the shaft intermediate bearing temp gauge goes 10 degrees over the last 6 hours of logged reading. Did it level off I ask, 'yes' comes the reply, did we cross the gulf stream yet? 'Yes' again well then your OK then!

A little perspective here in that forgetting about the A/F effect a 15PSI system gives a 250 DEG F boiling point. Now I know that sure A/F degrades heat transfer and one can see localized higher temps etc but however that is 40 DEG more than 210.

One thing those busy towing in the summer may well wish to consider is cutting back the A/F to say 20% for better heat transfer etc. This would be more advantageous than the minimal boiling point rise the 50% mix gives you.

Cheers
Nobby

 

[Acesneights1]

If you hit red on a 95+ Gauge, your way too hot. Gm Gauges leave alot to be desired.

 

[orrum]

So my gauge goes 100-210-260 and the redline is at 250. I tow at 185 -190 local on the flat with two horses and not towing about 165. Need to go to the mountains and find out 4 sure wht she can handle. No idea how many tubes, cant see anyway to tell. I am starting to wonder if my truck is several trucks put together????

 

[Big T]

Thanks Jeff maybe I'll try one.

I am almost sorry I started this post, 1st I got smart ass comments back from Big T that helped NO one.

SORRY Big T & anyone else that needs thicker skin!

It is I who needs the thicker skin. Wasn't me who was overreacting to a post that simply confirmed that buying a 7.3L Ford just might be the better choice for you.

Crankme69, maybe a difference in approach is in order? Here's my first post on this here website:

Hello From SoCal,

Steve here from Fullerton, CA. Have owned a 1995 GMC 2500 Suburban 4x4 w/ 6.5TD since 1998. Been through all the issues and was a member of Jim's DieselPage for awhile. Truck is basically stock save for Banks 3" down pipe and 4" catback and the upgrade water pump and dual T-stats. 156K miles on it, lots of it towing boats. Have a 20' Blackman center console with Volve AQAD31A diesel and DP 290 drive for saltwater fishing and a Ranger 198 Bass Boat with Yamaha F115 four stroke for freshwater fishing. I do all types of fishing from marlin on the salt to dry fly fishing for trout on the streams.

Originally bought this truck to be able to tow my Blackman down the Baja to fish the blue marlin at the East Cape in August. I soon realized that the engine would not be able to withstand the heat of a Baja summer while pulling a 6,000 lb boat up a steep grade. So I turned to the web to find solutions. The basic mods I've done have really cooled the engine down, but still feel there is more I can do. Just never bit the bullet for an intercooler as I do like to take this truck off road. I have yet to tow the Blackman down to the East Cape. Something about raising a teenager, remodeling home, career, etc. getting in the way. Very interested in the ATT Turbo solution. I regularly take this truck up mountains as we have a place on Big Bear Lake (6,750'). Towing the bass boat up there is an interesting experience watching the gauges. Probably something I would not do during the heat of summer.

Love sites like this where I can obtain good info from crazy gear heads who love working on their trucks.

Steve

I've been happy with the results from the modifications suggested by the many experienced 6.5 diesel types here on this forum. You can find none better. Several times you've come here and posted whiny posts how you hate the 6.5. This time whining that you're going to buy a 7.3 Ford. I agreed that you should and be done with it. Many friends have and love the 7.3 Ford. I considered a 7.3 Excursion and almost bought one. The 6.5 takes some special treatment and care to be a solid performer. By your whine, it did not seem that you were up to it.

 

[Turbine Doc]

I'm late to the party here been running flat out last 3 mos for work, had some dead time tonight as we are nearing completion of another job I'm working on.

Most of what I would say has been covered already, I pull probably as big a load as anybody does on occasion when hooked up to my backhoe, summer in Ms as hot as it comes I have yet to overheat even during the one time the lower IC hose blew out halfway home and I had to limp home last 50 miles in basically N/A mode. Currently my IC sits on a shelf after some testing with the ATT indicating that so far I've not needed it, located beside my WMI that I've yet to install (too many jobs not enough time to tweak the truck) since upgrading to the ATT on both my truck & my burb.

18k is the load I pull on a GN trailer; yes more than a K1500 is supposed to pull (another whole discussion we've had before) anyway with mods in my signature it can be done, no special radiator required just a clean one. With a/c on or off no difference to heat load, temps monitored with MT2500 scanner showing 195F peak while indicated 210F on dash gauge. (Before getting alarmed at indicated dash temps, confirm they are correct GM instrumentation is somewhat lacking at times)

210F isn't death knell for the 6.5 but if towing sustained there; it is an indication point it is time to start doing some maintenance to find out why you are sustaining that operating temp.

On a grade with a system that isn't up to par I would expect excursions past 210F which isn't ideal but not a death knell either so long as temp does not continue to rise or fails to fall back down after the grade has been overcome, 230F is most I'd push a 6.5 and that is on high side of my comfort zone, slow down if need be driving at 55-60 is beter than trying to sustain 70-75 if you rig is having "issues" poping it's cork and you walking to the offramp for assistance or dialing your cell for a tow.

Clean rad/ac condenser core-healthy fan clutch-healthy stats-proper coolant mix are basic building blocks for towing.

H/o water pump, later year fan (composite is my preference), retuned fan clutch,additional lube oil capacity,additional trans capacity/cooling make the setup very robust.

Cooler IAT via post compression cooling or better turbo that doesn't add to heat load are the real way to go to build a tow machine, remembering with GM turbo or any turbo boosting above 10+ psi boost the charge air temps change from a gradual slope to and arrow almost straight up if temps were plotted on a graph. ATT does a better job with this & another discussion thread beaten to death already elsewhere.

Thermodynamics required to balance the system is as much art/practical solutions as math & science allows for; my setup while probably lacking in some areas works for me, & should work on most others was put together after much time and reflection with Bill Heath who is scoffed by some but admired by far more as a reliable source of great 6.5 information.

Every vehicle has it's own particulars and with requisite effort a soultion can be found, I have 2 6.5s in my stable both are 195F or less loaded or unloaded, I've worked on a number of them in the deep South (hot cliamates) & have thus far with due dilligence been able to resolve the "overheat" issues clamed to be the negative some claim to have that keeps the 6.5 from being an adequate tow rig. As far as the 7.3 goes it's a reliable enough Diesel but not without it's own issues especially when comparing the IDI 6.9/7.3 to the IDI 6.5, 6.5 comes out on top. A 6.5 tweaked to stock 7.3 Stroke I still lean to the 6.5, event to the mildly tweaked stroke a draw, problem is the 6.5 IDI finishes out without extreeme modification to where the 7.3 & other "modern" DI engines start building for power.

I loose no sleep for anything I put to my 6.5, I know it's limitations and live/drive to them, that said 70-75 mph & some reserve power with a 18k load is all I'll ever need to move so I'm well pleased. I've driven "Fancy Gap" pass and most of the east coast mountains/hills and no shortage of power or signs of overheat, I don't own a 5er so maybe my experience isn't same as others, and I can't add more to that discussion for that setup.

I'm not sure why the OPs setup has left him so dis-satisfied as my setup as well as many others are makeing the grade.

 

[Acesneights1]

To be fair Tim, I do want to point out on your Pickup you are running Heath's Balance flow as well. To my knowledge you are the only one running it. As far as 7.3 PS I have owned one and my father owned one and there is no comparison. Ford got it right with that combination. It's near impossible to overhat a Healthy maintained Stroke. Of course if you even have to work on the damn thing, you'll be hating life. Aside from the waterpump, everything on it is a bitch to do and tres expensive. I still think a bigger rad will do alot. I'll know shortly. I just can't get out of my head having owned older versions with the copper rads and never having any issue that it's not a factor. Hey if you didn't sit around scratching your head about turbos, there wouldn't be an ATT right ?? If I fail, then it put's it to rest once and for all but if I'm right alot of guys are gonna be at the junky looking for CUCV rads...
The first appearence of the 6.5TD in 1993 sported a copper brass rad and then GM went to the alum/plastic one in 94...Now put this in your pipe and smoke it for a sec...
GM(or any manuf) doesn't look to make improvements the second year of production right ? Hell they usually don't get it right till the last years (case in point the 99+ WP's) So I'd be hard pressed to believe they went to the plastic rads in 94 as an improvement. Nope I think it was to save money, plain and simple.

I could try a poll to see if 93 owners with copper rads have the same issues as those 94+ but it would be biased anyway as the difference in fuel delivery of the DB2 vs DS4. I own both side by side and the DB2 puts out less fuel and substantially less egts atleast for me anyway.

However I would be curious to know how many rows most people have in thier Alum/plastic rads factory. 2 or 3 ?

 

[orrum]

Mornin Doc!!! Fancy Gap, yes its on my way home to Va. where I grew up. Gonna try it with my 6.2 and gooseneck horse trailer, about 6000 lbs total. How do u think I will do??? I have nitemares of just plain running out of steam and having to back down that mountain or worse over the side of it!!!! interstate 74 is a beautiful drive but thats the second worse pull I have ever made. My 1985 454 Crew cab dually would eat it up but the gas gauge actually moved as u watched it!

Ace how do I tel how many rows I have in my new aluminum plastic radiator??? Wish I would of kept my old one.

 

[Big T]

Ace, the '95 I gave to Colbythekid is running the Heath balance flow water pump and the composite fan. That was one of the first things I did (plus timing chain and reversing the CPS) when I arrived here. That made a major difference in cooling.

I had that '95 offroad going up a rock strewn jeep trail to the top of lightning gulch peak at 9,500'. Once I was on the trail, there was really no stopping as you could not turn around and you could not generate much airflow at that speed. It was rugged, slow and the engine coolant temp hit 230 when I got to the top. I left the engine running on the summit to cool it down. Going down it ran at 185. It was then that I moved to install the Heath cooling upgrades.

 

[Turbine Doc]

No balance flow on the burb Kenny & no overheats, I don't think the BF on my truck is the edge you think it is. When I 1st got the burb it was an over-heater but a DEEP CLEANING of rad & condenser fixed that, also upgrade to spin on retuned fan-clutch & Heath water pump.

My BF on the truck is still there because I have an OE 4 bolt pump on the truck and that was direction Bill went with those before going to current setup due to costs and equally effective result from current setup he sells BF no longer offered as the choice for the 6.5 in our rigs.

My project engine going in will have latest pump from Bil but I won't be putting back on the BF as paired with that pump it is supposed to be counterproductive; so I'll have some comparative data one day.

 

[GM Guy]

To be fair Tim, I do want to point out on your Pickup you are running Heath's Balance flow as well. To my knowledge you are the only one running it. As far as 7.3 PS I have owned one and my father owned one and there is no comparison. Ford got it right with that combination. It's near impossible to overhat a Healthy maintained Stroke. Of course if you even have to work on the damn thing, you'll be hating life. Aside from the waterpump, everything on it is a bitch to do and tres expensive. I still think a bigger rad will do alot. I'll know shortly. I just can't get out of my head having owned older versions with the copper rads and never having any issue that it's not a factor. Hey if you didn't sit around scratching your head about turbos, there wouldn't be an ATT right ?? If I fail, then it put's it to rest once and for all but if I'm right alot of guys are gonna be at the junky looking for CUCV rads...
The first appearence of the 6.5TD in 1993 sported a copper brass rad and then GM went to the alum/plastic one in 94...Now put this in your pipe and smoke it for a sec...
GM(or any manuf) doesn't look to make improvements the second year of production right ? Hell they usually don't get it right till the last years (case in point the 99+ WP's) So I'd be hard pressed to believe they went to the plastic rads in 94 as an improvement. Nope I think it was to save money, plain and simple.

I could try a poll to see if 93 owners with copper rads have the same issues as those 94+ but it would be biased anyway as the difference in fuel delivery of the DB2 vs DS4. I own both side by side and the DB2 puts out less fuel and substantially less egts atleast for me anyway.

However I would be curious to know how many rows most people have in thier Alum/plastic rads factory. 2 or 3 ?

it was actually 92. dad owns a 92 HD, and I am am dealing on a dead 92 3500SRW, but you are 100 percent correct, both dads 92 and 93 have copper radiators.

Dads 92 behaved nicely a few summers back loaded to 23K, I was able to play with the pedal and the defrost and keep it under 210, and didnt pay close enough attention on one hill, and it got to 230, but we havent cleaned it at all, still bone stock cooling system. it is 5 speed, yes, but it does have the built in oil cooler for the engine oil, so it was still getting a workout.

I do think you are on to something, as that HD doesnt have hear the heating issues with the brass radiator, although it doesnt have a condenser, due to it being ordered with a/c delete, surely that helps as well.

 

[btfarm]

I do think you are on to something, as that HD doesnt have near the heating issues with the brass radiator, although it doesnt have a condenser, due to it being ordered with a/c delete, surely that helps as well.

I'd venture to guess that would make a big difference. I know it did on several hotrod gasser trucks for me over the years.

 

[Acesneights1]

No balance flow on the burb Kenny & no overheats, I don't think the BF on my truck is the edge you think it is. When I 1st got the burb it was an over-heater but a DEEP CLEANING of rad & condenser fixed that, also upgrade to spin on retuned fan-clutch & Heath water pump.

My BF on the truck is still there because I have an OE 4 bolt pump on the truck and that was direction Bill went with those before going to current setup due to costs and equally effective result from current setup he sells BF no longer offered as the choice for the 6.5 in our rigs.

My project engine going in will have latest pump from Bil but I won't be putting back on the BF as paired with that pump it is supposed to be counterproductive; so I'll have some comparative data one day.

Ahhh...but your not towing the 18k gooseneck with your burb either.... I got to see that Balance flow and thought it was pretty neat actually. Where it ties into the therm housing, is it pre thermostat or post ? I don't remember. If I could tig weld I'd make it myself. Hardest part is the bung in the housing.

 

[Acesneights1]

So anyone got data on how many rows they got ?
Orrum, your's should be easy to count. Take the rad cap off and look in there. The 94+ trucks are a likttle harder to see as no rad cap.