heating problem

[jaynes]

Although I have a piece of cardboard infront of my radiator, the only way the cab will warm up enough to make me stop shaking from hypothermia is to keep my foot on the floor while driving 85 mph down the highway. Now, I'm just guessing, but shouldn't the heat be working better than that? I know this is a diesel, and the cooling system works great, but MAN is it cold! I freeze my butt off. Is this normal or is there something wrong with my thermostat?



jaynes

 

[prototech]

Hey jaynes,

there is a valve under the hood on the right side by the fire wall that controls the flow of hot coolant to the heater core. there should be a cable connected to it which comes from your hot-cold lever on the dash. I have had the cable come off before only I had the opposite problem, I couldnt get the A/C to work. that would be my first guess. Is your temp gauge registering any heat above the C ? If not check your thermostat it might be stuck open.

also I have had a heater hose kink on another vehicle. It might be time to repalce some heater hoses. Just a few thing to check.



On a turbo upgrade, I just put a 16cm housing on my truck and it has made a huge improvement!!! It really brought up the low end and spools up the turbo allot sooner, the housing was $150 bucks and was fairly simple to install, I highly recomend it!

Proto

 

[jaynes]

Cool, proto. It does get warm, or luke warm, I should say, but only if I'm pushing it real hard. The only time the gauge reads in the middle is in the summer time when it's hot. In the winter, like now, it barely reaches the first line. It usually stays between the C and the first line. I think my thermo must be stuck open.



As for the turbo, the 16cm was going to be my first purchase. I've also had some guys tell me to do the HX-35/16cm combo, even though I don't pull anything. What do you think of that setup? Remember, most of the driving I do is in the city, and sometimes I drive on the highway alot, too. Would that set up do me any good?



jaynes

 

[bgilbert]

Jaynes, is your fan clutch good? It could be locked up and constantly engaged, cooling the system. With a properly operating system, your truck should reach 'operating' temps year round. Might take a little longer in cold weather. I had the same problem last winter, truck would not reach operating temp, that is the same mark on the temp gauge as in the summer time. Fan clutch was locked up, t-stat was stuck open, replaced both, now have heat within a reasonable time. Bill

 

[Excessive Force]

Why don't you go fanless. I remove the fan in the fall,and don't have to put it back on until june. Sometimes i even run a piece of cardboard between the rad/intercooler. I never have a problrm with overheating,or lack of heat.

 

[MMiller]

I'm not sure I would remove the fan on a first gen, guess it depends were you live. Around here I carry a piece of cardboard for the days under about 10 degrees, but the rest of the time nothing in front of the radiator and fan on. Don't have any trouble getting the engine to heat up. I really have to watch my truck, if it is above 15 degrees or so it will run pretty warm(ie hotter than normal) with about half the radiator blocked off.



I vote checking the fan clutch then the thermostat.



My 90 will make engine temp but blow no heat. I will look for the valve, then I was thinking about replacing the heater core.



Michael

 

[Excessive Force]

I read a while back that a fan eats 20 hp@ 60 mph... .

 

[prototech]

hey jaynes,

sorry, I gave a little mis-information yesterday. there is no cable to the heater switch, it is a vacuum control, I looked at it on my truck today. any way it sounds like you could have one of a few problems. I don't know how cold it gets where you're at but it has been a few degrees below freezing here for the last week and my truck still warms up to the 1/3 mark on the temp gauge after about 7-10 minutes of driving.

On the turbo thing again, I don't know that much about the different turbo's that came on our trucks. I need to find out which one I have, It says HCI and all of the #'s start with 35. If any one knows or can tell me what to look for I would greatly appreciate it!

Proto

 

[dpuckett]

jaynes-

I'd second the t-stat idea. I've had a few stick open, but cardboard helped till I got around to replacing it. If you're only getting up to the line between the C and the first line, you're running WAY too cold. All of mine have run on or aroudn the second line that is connected in the sweep. Get a 185deg unit from Cummins, and change it out. i had a fan clutch crapout on me- came unbolted from the fan clutch- and I took it off on the side of I25. Drove that way for 3 weeks, loaded and empty, no problem.



AS for your turbo, I'd say yes, the PDR 35-16 would be a good upgrade. Give you a decent bottom end, yet free flowing enough to do ok down the highway. See my reader's rig for pics of a HX35 on a non-IC engine. The outer hose is 2-3/4" silicone turbo hose. Kind of pricey, but it stretches and will go with some PB Blaster to help out. Any questions, PM or email me.



prototech-

If your turbo is stock, it is a H1C, came with a 21cm housing. It is good for about 25-28psi boost, then starts to loose effeciency- drive pressure is greater than the boost you get from it, and the additional air is hotter than at lower pressures. An HX35 looks real similar, but is good to about 33-35 psi boost. The exhaust housings interchange; turbo drain bolts up, and the intake hose fits right on there. There should be a tag on the front of it, close to where it flares out to go to the intercooler elbow. Should have an assembly#, type (H1C), and a serial number (?)

 

[MMiller]

I believe the fan eats hp, no doubt. But its kinda necessary evil too right? I have electric fans on my 75 dodge, but have never went to them on anything else yet. That would be about the best of both worlds. Turn it off in the winter, set the fan stat in the summer, and have no hp loss! I was just saying that a first gen doesn't have the cooling package a newer truck has, and where I live it wouldn't be worth the trouble of removing the fan. I would remove and install it prolly a half a dozen times during the winter, because of temp swings.



Michael

 

[Excessive Force]

When i originally took it off i made a wrench to fit the nut out of some scrap steel,and welded a piece of rod to it for a handle. I keep the fan behind the seat along with the wrench,and if i have a problem i can put it back on in less time than it takes to fuel up.

 

[jaynes]

Thanks guys! Yeah, I'll have to check that tstat. Right now, it's starting to warm up, and the engine got pretty warm today. The only time it reaches the middle mark is in the summer. Then when I pull off the highway after running WOT for an hour, I have to put my foot on the gas with my left foot on the brake (auto transmission) to keep the idle up, cause it idles so low once the engine gets hot that the oil press. light comes on. Cummins said that's because the fuel gets thinned out. But I don't thing that I'm supposed to have to manually idle it up to keep oil press, right?? Anyway, I'll check that thermo. Thanks, Puckett, for the turbo input. I'm going to be purchasing 16 cm from PDR really soon here, then later a HX35.



jaynes

 

[prototech]

hey thanks for the info dpucket,

proto

 

[dpuckett]

You're welcome, guys. DOnt forget, you will need to change intake hoses if you go from a non-IC truck to a HX35, et al.



Daniel

 

[jaynes]

For now i'm just gonna go with the 16cm housing. The 35 would be later, and I'll get ahold of you if I have any problems with the change out. Thanks for all the info!



Josh