engine cooling with a heavy load?

[Flexiheep]

Question for the folks who are running a turned up pump etc and pulling the heavier/less aerodynamic loads. Are you doing anything special to keep the engine temp under control?

A little background for my question is that my wife and I just bought a 30 ft TT that sits almost 12 feet tall, and about 10K when loaded. I am happy with my power level, but a recent trip where the air temps were around 80 degrees showed that the water temp climbs rapidly. Under load (3rd gear, 2300 rpm, 1250 pyro, and 230 transmission) It never gets to the top of the last third, but it gets close.

Again I am happy with the power and speeds I can run, but would like to have it run cool, even in 100 plus heat with the A/C on and the family inside..... Maybe I am asking too much



With the guys making big power here I figure someone has played with cooling before and has a couple ideas. I am planning to ditch the oil/water transmission cooler to lessen that load (twin underbed fan assist coolers planned). I have seen a passing comment about a 2nd gen radiator (Napa online shows it is a foot wider) but I haven't looked to see if it is reasonable to think I could mount one... ...



Anyone have experience? My goal is to put 200-230 hp to the road and not have to worry about cooling it even in the summer.....

 

[DVolk]

engine cooling with a heavy load

Id check the fan clutch make shure its in good shape and make shure the radaitor is clean , if the timing is off the temp will raise as well



mine was off a bit after the pump backed off some how .



1250 exhaust temp id watch it doing that , its easier to drop a gear

you can melt pistons at 1300 keep that in mind

 

[JLEONARD]

I'd consider installing dual electric fans and lose the mechanical fan.

 

[NIsaacs]

I'd consider installing dual electric fans and lose the mechanical fan.

Are you sure? He is towing heavy in hot weather.





"NICK"

 

[TWorline]

If the 2nd Gen rad will fit in the core support you would also need to retrofit a 2nd Gen intercooler as well.

 

[cerberusiam]

A little background for my question is that my wife and I just bought a 30 ft TT that sits almost 12 feet tall, and about 10K when loaded. I am happy with my power level, but a recent trip where the air temps were around 80 degrees showed that the water temp climbs rapidly. Under load (3rd gear, 2300 rpm, 1250 pyro, and 230 transmission) It never gets to the top of the last third, but it gets close.

5K over GCVW, trans temps into the danger zone, water temps in the uh-oh zone?? Asking a little much?



Now you see why the weight ratings were what they were.



Assuming you have had the radiator rodded and boiled, a manual temp gauge might be a good investment to see if it is actually getting hot. You have some work to do if you want to do that in summer hot and keep the AC on.



Good luck.

 

[Flexiheep]

Asking too much, I don't think so.....

Am I pushing limits, yes, am I asking too much, I really don't think so. Who here tows within the "limits" I mean, who tows only 5K with their 1st gen? I can get a Ford explorer to do that!

Well, what ever. I know what I want to do, and I know I can't find a new truck that I want to do it with. Too many electronics, no long beds available (megacab), and other things... ... .



Since no one has really talked about what they have done to keep their cool, so I am thinking it really isn't a problem with everything in good shape?



I don't know I guess with all the work I am thinking of putting into the truck with the crew conversion I do not want to have problems later because I didn't take the extra step to ensure reliability. My plan for the engine is to get a pump rebuild (3K gsk inc), 190 injectors, new turbo, 4" exhaust, and hopefully be happy. I don't want a ton of power, but enough to do the job. Oh well, any more ideas guys, or is it really not a problem?

 

[bgilbert]

Definately a mechanical water temp gauge, wipe your behind with the stock water temp gauge. This way you'll know exactly what it's running.



Then maybe on some long pulls you and the family might have to sweat it out a bit by turning off the AC. I can't help much since I don't tow.

 

[Niki]

I assume your fan shroud is present and not broken, and that rubber flap that lays between the core support and radiator is there? I only ask because I've seen a ton of first gens missing these items. I think you're on the right track w/ the 2 trans coolers and disconnecting the trans lines from the heat exchanger, I'd leave it there though. According to my 93 service manual an auto truck holds one more quart of coolant, and I bet its in the heat exchanger. Not much, but every bit helps. Also maybe do a coolant flush and run 70% water in the summer, it'll run cooler although it'll lower your boiling point slightly.

 

[dpuckett]

The heat exchanger under the exhaust manifold is more for warming up the transmission in cold weather- I'd leave it unless it leaks.



I'd install a tighter convertor and do some valve body adjustments. Getting a bigger cooler is a must if you are running in 100deg temps. I'd opt for one in the grille, personally. (Upon re-reading your signature, this has already been done).



1250 is good for EGT if it is pre turbo. Banks (who are not known for pushing the envelope) says you can run 1300 all day long without damage. I'd also stay with a 16cm housing on the turbo, since your windsail will put a bigger load on the engine and demand more top end (in terms of load) flow.



How are your injectors? T-stat? Any leaks anywhere?



Check your intake system for boost leaks.



I towed 10K or so all summer in 2000 with (now) my Mom' 92 in all stock form. Didnt have a transmission temp gauge, but water never got hot- got up to one line above "normal running temp". I've towed as high as 24K with a manual, but that was in winter.



Daniel

 

[DBF]

With the guys making big power here I figure someone has played with cooling before and has a couple ideas. I am planning to ditch the oil/water transmission cooler to lessen that load (twin underbed fan assist coolers planned). I have seen a passing comment about a 2nd gen radiator (Napa online shows it is a foot wider) but I haven't looked to see if it is reasonable to think I could mount one... ...



Anyone have experience? My goal is to put 200-230 hp to the road and not have to worry about cooling it even in the summer.....

I had to eliminate the fluid/water exchanger due to leakage. I tow a 11. 5' tall trailer; it's just like pulling a wall at high speeds. Biggest thing to help the engine cooling was the radiator rodding & cleaning. Biggest thing to help the trans cooling was the two underbed coolers.



Because you live where you might want the exchanger to help heat up the trans fluid on cool days, you might want to keep it. If there's good cooling on both sides (engine and trans), it won't have much to do.



Some notes and pictures are in my gallery.



Oh, yeah. Get and install the 3200rpm pump governor spring. Big help in some circumstances.



Regards, DBF

 

[MMiller]

I've never towed with an auto, but like said above get a tigh convertor, or even step up to a lockup convertor transmission, this will help with transmission temps.



As far as engine temps, I tow heavy, and only one day in the last 7 years of running 235 hp, I've had engine temp problems. Last Memorial day weekend on the way home hauling heavy, we were pulling into a bad head wind, it was hot and humid. It was requiring all the power I had to drive 60 mph, and engine temp would heat right up.



I need to ditch the 305 tires, they are too tall for towing on my truck, the next set will be some 32" tires, and my temps will go down, engine temp and pryo. Less load.



Michael

 

[Flexiheep]

good info

Well it appears that when all is in order there shouldn't really be a problem with heat.

I have been putting the miles on my truck, but I think they have caught up to me now. I think the truck is just getting tired, the injection system needs attention, as the mileage has dropped, egts are up and the exhaust odor has changed in the last couple months. The last time the radiator was cleaned the shop didn't rod it out, they just did a circulation chemical cleaner, that was about 4 years ago. Getting the new transmission/converter in there did wonders for lowering the transmission temps over the worn out stocker with 255K on it, now I just need to get the remaining heat out of the radiator.



My plan goes something like this:



Radiator rodded/worked over (will keep an eye out for a second gen rad/IC)

Twin underbed coolers with a bypass for warm up (may use the exchanger)

IP rebuild/modded (3200 spring to start, advance timing)

Bosch 190 injectors (current are untouched stock)

Upgraded turbo (either 16 housing or maybe a HX35, not sure which for my power level yet)

Full 4" exhaust with muffler (helps with the stealth factor)



Some of this will be done soon, and some will have to wait till the crew conversion later this year.





Thanks for the info all, it looks like it will be ok to run with the stock radiator unless I find a screaming deal on a second gen rad/IC to put in.

 

[KOG]

If you're not planning on off roading, an air dam below the front bumper is quite effective at forcing more air through the radiator. The closer to the ground you get it the more good it will do. I've used industrial rubber belting for the lower 4-6" of air dams to avoid breaking them on curbs. I doubt that you'll much notice the reduced front end lift that the air dam also provides. More noticeable on a Porsche than on a CTD I suspect.

 

[RWWinslow]

I had gradual heat buildup problems with mine and here is it what it took to cool it back down:



1) New injectors. 5 of the 6 were not flowing and/or were not at proper lift pressure.



2) New fan clutch. The old one was not turning the fan adequately.



3) New radiator. The original radiator was plated out with mineral deposits on the inside from tap water being used to re-fill the system. (Always used distilled water or pre-mix. ) You can buy a new radiator from JMAC or others for the cost of having an old one worked on. The cross flow radiators also remove a lot more heat than than top tank models on the early 91's.



4) Clean out the fins on the A/C condenser - use soap and water and a gentle flow of water out of the hose to get this really clean - it will take a couple of hours to properly clean this coil - I took the grill front off to get to everything.



5) Timed the engine to correct specs - this made quite a difference in exhaust odor, also.

 

[dpuckett]

Dont the 2ndGen radiators have plastic end tanks? If so, I'd stick with the original.



DP

 

[DValentine]

I tried the two electric fans... . Back to the fan clutch. Towing 9000 pound fiver... . and the two fans didn't cut it. Even with no load the temp would come up in 90 degree ambiant temps. I also put on a manual gauge... . 250-260 when the needle is on the H on the stock dash gauge. 230 on the next slash to the left.



Dave

 

["Mad Max"]

Flex, I also think that the factory parts are up to the job without needing additional aftermarket parts, but as they get old they can lose their effectiveness. Having the radiator cleaned and inspected I think would be the biggest payoff, and having a fresh fan clutch second. After that, just so long as the shroud and lines are tight I think you'd be good to go. I would also definitely recommend both a mechanical oil pressure and water temp gauge. I did both to my 1st gen, and found my truck was running better than I thought.

Another point - it's about power getting to the ground, and the transmission is really the big seller here. Converter is everything. I had a TCI unit in my rig, and when I moved to Colorado from California I came across I-40, made a left at Alberquerque, and headed up the 1-hour-long grade into southern Colorado. During that ascent my truck got the hottest it had ever got in it's life. At the worst point, I was still on overdrive maintaining ~60 mph and I was at 18,000 lbs gross (truck and trailer). I had POD's, an HX-35/16, pump just about maxed, but no spring. Still, at the worst point the engine was at 225* and the transmission was at it's all-time high of 235*, pyro was holding steady at 1200*, and about 10 psi boost. I was just cruising and watching the pyro. I was asking a lot of the truck, and I wanted to 'push' it a bit to see what the old girl really had. If I had a lock-up converter it would have been a little bit different because it would have been 'all motor'. As it was, the radiator was also trying to cool the transmission. The bed cooler was on the whole time, but definitely the truck's cooling systems did their jobs magnificiently. I was impressed as hell that I could pull that much weight up that grade with those temps. In the end, at the top of the grade, all the temps just started coming down, pyro as well, so more throttle came on, and the speed went back up to 75 mph.



I'd definitely install machanical water temp and oil pressure gauges. My readers rides has pics. There's just no better way to know what the numbers really are without 'em. But for sure, if you can add another transmission cooler then you'll be asking less of the radiator which will in turn give more to the engine cooling. So I'd say either replace the factory bed cooler with a bigger/better version or add another one in line with the factory unit. Keeping the transmission cooler can never hurt.



- M2

 

[dpuckett]

ANd you cant forget the elevation, MM. What is the state line on I25- 4500ft?