Engine overheating

[quote:ba65c9a08f="dragonlady22"]I recently had to have my heater core replaced on my 2002 dodge ram quad cab. Now I have a problem with my truck overheating when pulling a hill. On the level it runs at the normal temperature. The coolant level is normal, and has not changed. After my husband has looked at it, he has no idea what it could be, and he is a mechanic! there are no lights, or codes.[/quote:ba65c9a08f]

Let him read this...
DIAGNOSIS AND TESTING - VISCOUS FAN DRIVE

NOISE

NOTE: It is normal for fan noise to be louder (roaring) when:


The underhood temperature is above the engagement point for the viscous drive coupling. This may occur when ambient (outside air temperature) is very high.
Engine loads and temperatures are high such as when towing a trailer.
Cool silicone fluid within the fan drive unit is being redistributed back to its normal disengaged (warm) position. This can occur during the first 15 seconds to one minute after engine start-up on a cold engine.
LEAKS
Viscous fan drive operation is not affected by small oil stains near the drive bearing. If leakage appears excessive, replace the fan drive unit.

VISCOUS DRIVE
If the fan assembly free-wheels without drag (the fan blades will revolve more than five turns when spun by hand), replace the fan drive. This spin test must be performed when the engine is cool. For the following test, the cooling system must be in good condition. It also will ensure against excessively high coolant temperature.

WARNING: BE SURE THAT THERE IS ADEQUATE FAN BLADE CLEARANCE BEFORE DRILLING.



Drill a 3.18 mm (1/8-inch) diameter hole in the top center of the fan shroud.
Obtain a dial thermometer with an 8 inch stem (or equivalent). It should have a range of -18°-to 105°C (0°to 220°F) . Insert thermometer through the hole in the shroud. Be sure that there is adequate clearance from the fan blades.
Connect a tachometer and an engine ignition timing light. The timing light is to be used as a strobe light. This step cannot be used on the diesel engine.
Block the air flow through the radiator. Secure a sheet of plastic in front of the radiator. Use tape at the top to secure the plastic and be sure that the air flow is blocked.
Be sure that the air conditioner (if equipped) is turned off. WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING. DO NOT STAND IN A DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
Start the engine and operate at 2400 rpm. Within ten minutes the air temperature (indicated on the dial thermometer) should be up to 88°C (190°F) . Fan drive engagement should start to occur at/between:
3.71- Automatic - 93°C - 99°C (200°F - 210°F)
3.71- Manual/4.7L Automatic/5.91- - 85°to 91°C (185°to 195°F)
4.71- Manual - 74°to 79°C (165°to 175°F)
Engagement is distinguishable by a definite increase in fan flow noise (roaring). The timing light also will indicate an increase in the speed of the fan.
When viscous drive engagement is verified, remove the plastic sheet. Fan drive disengagement should start to occur at or between:
3.7L Automatic - 76°C to 81°C (168°F to 178°F)
3.7L Manual/4.7L Auto/5.9L - 67°C to 73°C (153°F to 163°F)
4.7L Manual - 56°C to 62°C (133°F to 143°F) A definite decrease of fan flow noise (roaring) should be noticed. If not, replace the defective viscous fan drive unit.
CAUTION: Some engines equipped with serpentine drive belts have reverse rotating fans and viscous fan drives. They are marked with the word REVERSE to designate their usage. Installation of the wrong fan or viscous fan drive can result in engine overheating.

CAUTION: If the viscous fan drive is replaced because of mechanical damage, the cooling fan blades should also be inspected. Inspect for fatigue cracks, loose blades, or loose rivets that could have resulted from excessive vibration. Replace fan blade assembly if any of these conditions are found. Also inspect water pump bearing and shaft assembly for any related damage due to a viscous fan drive malfunction.

Thank you for that. I took it to a shop today, and it seems to be the head gasket. It's not a fully blown one, but sooner or later would have been.

I found this guide that helped me too

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Thanks for the tips though, and i have it saved!

Ok, it seemed to have a problem with the fan clutch; not a headgasket. however, after replacing that, the truck still overheats pulling hills, just not to the point of boiling over. I also get a faint funny smell from the vents, hot or cold. something burnt, and chemical but I cannot recognize it. This is a daily driver, and I really need it fixed instead of replacing all kinds of parts! I've replaced the heater core, now the fan clutch.......
also, cannot find any leaks of coolant, nor is there any coolant loss.
Thanks!

My dodge keeps overheating at highway speeds but cools to normal temp in town. we have already replaced the radiator, thermostat, hoses, fan clutch, and the water pump 5 times as along with the overheating there is a vibration, and then something happens in the pump and all antifreeze comes out through the pump. We are now down to replacing the only thing left that may be out of balance and causing the pumps to fail, and that is the fan blade itself. Please help me if you can i would greatly appreciate it. Thanks Alot

I think you are on the right path with changing the fan blade.

Overheats only at highway speeds. Runs normally in town driving. Already flushed coolant and replaced. Replaced thermostat. No unusual indications other than overheating. Runs smoothly, no noises, no leaks. Water seems to be circulating ok.

Try bleeding the cooling system

Always bleed air from cooling system after replacing coolant. Set heater for maximum heat. Remove radiator cap. Loosen drain plug and remove drain bolt (if equipped) from engine block. Drain coolant reservoir. Fill coolant reservoir to MAX mark with 50/50 water-coolant mixture. Loosen bleed bolt and fill radiator up to base of filler neck. Close bleed bolt when coolant flows out without bubbles. Tighten bleed bolt. With radiator cap removed, start and operate engine to normal operating temperature. Add coolant if necessary and check for leaks.

Do you mean to loosen the drain plug at the bottom of the radiator and then the bleed plug just until the reservoir is drained? Close the drain plug and refill the reservoir until full again and run until no bubbles are coming from the bleed plug. Should the cap be on during this process?

Drain coolant reservoir. Empty it out-okay if it has a bleed bolt loosen it and fill the radiator till it starts flowing out of the bleeder bolt with no bubbles.

Or just remove radiator cap and run engine till it gets up to operating temperature and keep filling it make sure the heater is on-till it no longer can take the coolant then put cap back on.

Followed your advice on coolant but it didn't help. I've since replaced the fan clutch, still no luck. This problem seems to kick in with just 5 or 10 minutes of 70mph speeds. I can drive 15-20 minutes to work at 55-60mph and it stays right on the midline. Radiator fins are clean.

I've tried the simple ones-Time to use heavy artillery

Get it block and pressure tested this will tell the tale what's causing it.

I have a real bad engine overheating problem. I have the 2002 dodge truck 4.7L engine. In town and short trips the temperature is normal but after driving at highway speeds for about an hour it will start overheating and finally will creep up to the max and the dash flashes a message and I have to shut it down. From then on I have to drive 15 minutes and stop let it cool off and start again. The heater never blows warm air. I changed the thermostat, radiator cap, water pump, new antifreeze/coolant. The radiator looks clean and I don’t think it is that. I made sure it was full of coolant and bleed air off the bleed screw. I took it to a mechanic and he checked for carbon monoxide in the radiator to see it had a blown head gasket and it had no carbon monoxide in the coolant. The mechanic said I probably had a steam pocket in the engine. I have tried everything to try and get the air pocket out and not sure it has one. Any suggestions?

Dude:

I had the same exact problem! Noone could figure it out. One eprson told me it was the water pump, another said tune-up. No leaks, good compression, etc. etc. Then as my wife was driving through the tunnel in Boston the engine went. Come to find out it was the head gasket. I did a lot of research & spoke to quite a few people that had the same problem. If your engine is the 4.7 litre I have been told it'sd a common problem but Dodge won't admit it. They told me it was tough luck as the 100,000 mile warranty had expired. Don't ever buy a Dodge vehicle again! If I was you I would have the head gaskets replaced or pay $4,500 for a new engine.

How about a new fan clutch if it don't lock up at hi temp you will overheat. Engine good a hott try spining blade should be quite a bit of resistence.

On my truck i recently had the timing chain cover gasket changed, since then it runs hot when idling while driving, it runs cool when under normal driving conditions above 55mph. I put a new water pump, radiator, new fan clutch, no lights come on it staying hot about 295 degrees, i have put 3 new thermostats for 195 degrees as required for the 360 engine, still runs hot. if you let it run without driving it at all the temp will not rise until after an hour, u hit the gas petal a lil an the temp goes down. What would else could be the problem here? I'm at my wits end on this.

Is the clutch fan working when it is at an idle?

[quote:4d73210c10="Jacobandnickolas"]Is the clutch fan working when it is at an idle?[/quote:4d73210c10] Yes, even put a new one on it. Could something have happened to the timing chain itself when the gasket was changed? It is not running the best but my spark plugs are fine. Would a blown head gasket cause this? There is no white smoke or water in the oil.

They really had no reason to touch the timing chain, so I will say no to that. As far as a head gasket, if there is no smoke, no oil in the coolant or coolant in the oil, the only way to check is by performing a compression test, but I questions that too.

I have to ask a crazy question. When it overheats, do you hear the coolant boiling or is it ever forced out of the radiator? If not, I'm questioning the temp sending unit. There may be too much resistance being created and it's telling you the engine is hotter than it really is.

Let me know.

Joe

[quote:a75d41c273="Jacobandnickolas"]They really had no reason to touch the timing chain, so I will say no to that. As far as a head gasket, if there is no smoke, no oil in the coolant or coolant in the oil, the only way to check is by performing a compression test, but I questions that too.

I have to ask a crazy question. When it overheats, do you hear the coolant boiling or is it ever forced out of the radiator? If not, I'm questioning the temp sending unit. There may be too much resistance being created and it's telling you the engine is hotter than it really is.

Let me know.

Joe[/quote:a75d41c273]
Only one time i heard it boiling in the top hose, so i put a pressure release cap on it so i could let the pressure off, the bottom hose was about 65 degrees and the top hose was around 90, i thought maybe one of the ports was blocked , back to the other thing antifreeze did go into the overflo jug and run out when the engine cooled it sucked it back out sometime, i'm already on the sending units, and a new temp gauge, i can let my truck idle for an hour and never get flow thru the radiator, then the temp warms up an i tap the gas pedal and it cools down, the temp gauge fluctuates back an fourth, none of this happened until that gasket was changed, my truck has never ran hot, nor has it ever had a bad miss in it. Thankyou for workin with me here.

Recently changed out my thermostat but my truck seems to start to overheat. Doesn't do it much when I'm on the highway but at stop lights and stop signs it starts run over the gauge toward the hot. Could this be my fan clutch going out. It does seem a little loose. Got plenty of coolant and isn't leaking anywhere.

Are you sure t-stat is in the right way? What I suggest at this point is to rent or borrow a temp gauge that you place in the top of the radiator to see if the temp is getting as high as you think it is. I really feel the sending unit is the problem. With the engine cold, open the radiator cap, place the thermometer in the coolant and allow the engine to warm up. then you will know exactly the temp of the coolant and if the gauge is correct.

Let me know what you find.

Joe

could be the clutch going out of the coolant shroud could be cracked or broken.

[quote:2972b9886b="Jacobandnickolas"]Are you sure t-stat is in the right way? What I suggest at this point is to rent or borrow a temp gauge that you place in the top of the radiator to see if the temp is getting as high as you think it is. I really feel the sending unit is the problem. With the engine cold, open the radiator cap, place the thermometer in the coolant and allow the engine to warm up. then you will know exactly the temp of the coolant and if the gauge is correct.

Let me know what you find.

Joe[/quote:2972b9886b]
Ok thankyou i will do that and get back with you. appreciate it.

[quote:12f30bffb0="blackop555"]could be the clutch going out of the coolant shroud could be cracked or broken.[/quote:12f30bffb0]

What could be cracked or broken? Coolant shroud?
The shroud is fine. I'm not getting any leaking at all anywhere. I'm guessing the fan clutch isn't pulling enough air into the radiator to keep the truck cool.

[quote:d69f3b47a4="Misse"][quote:d69f3b47a4="Jacobandnickolas"]Are you sure t-stat is in the right way? What I suggest at this point is to rent or borrow a temp gauge that you place in the top of the radiator to see if the temp is getting as high as you think it is. I really feel the sending unit is the problem. With the engine cold, open the radiator cap, place the thermometer in the coolant and allow the engine to warm up. then you will know exactly the temp of the coolant and if the gauge is correct.

Let me know what you find.

Joe[/quote:d69f3b47a4]
Ok thankyou i will do that and get back with you.
appreciate it.[/quote:d69f3b47a4]
Well after a day long of messin with my truck, i figured it out, you might wanna grab a seat cause you ain't gonna believe what it was. My truck is designed to run on a certain kind of antifreeze, i have always put in it the pink kind, or 50/50, after the timing chain cover gasket was changed the garage that actually changed it put back in it the full strength prestone antifreeze, and dumb me never even thought twice about it until today, flushed it out completely and added the 50/50 it is under normal operating temp, the sending unit is good as was it before and my truck is running like a brand new one. I just wanna say thanks for your input and all ur advice, so from here on out i will do all my work as i have done before and never intend to take it back to a garage again, i messed up a good thing just because i was to lazy to do a 3.5 hour job. thanks a million, really appreciated your time and advice. Misse

the shroud. the black thing around the fan that acts as a suction from the fan to suck the air through the radiator to cool it.

Trying to find out what would cause my Ram to overheat within a mile of driving.
I tried last night to disipate some of the heat buildup by turning on the heat and noticed there was still cool/cold air coming from the vents. After about 15 min hot air started coming out. I checked the oil when it cooled down and saw it was a quart low. Would being a quart low cause my engine to overheat that fast at low speeds or does this seem to be a thermostat issue?

Hi
Thermostat replacement is good idea also consider flush at that time. Check to see if fan clutch is locking up when at op. temp. ie. should be hard to turn by hand.
Let me know
Thanks for donate

Turned out to be a hairline crack in the radiator frame. Replaced the radiator as well as the thermostat and all is good. Autozone had a direct replacement that made the swap really easy. Thanks for the response and informative website.

Glad it worked out those plastic tanks make it hard to find a leak. Join us again

Dodge ram 1500 overheated, stalled, cooled down, refill with water, tough to start, very low power, billowing white very damp vapor from exhaust pipe

Sounds like the head gasket(s) failed. Coolant is getting into the combustion chambers, not good at all. The engine may need some major repairs.

We have a dodge ram van 1500 that we bought to pull a trailer (1100 empty + 800 lb motorcycle) and the van runs just at or under the red section of hot on the gauge. Replaced thermostat, no didderence... Would a transmission cooler that u-haul sells improve this?

Try the U-Haul transmission cooler don't work have the transmission checked out-How's the transmission fluid condition and level?

The trans fluid is fine and when they suggested the trans cooler I wondered if it would really have any effect on the cooling system... Don't want to waste money. Thanks!

It won't, I'll probably cool the transmission faster to prevent the engine from overheating- due to the weight you're pulling/long hauls

We have a dodge ram van 1500 that we bought to pull a trailer (1100 empty + 800 lb motorcycle) and the van runs just at or under the red section of hot on the gauge. Replaced thermostat, no didderence... Would a transmission cooler that u-haul is trying to sell us fix this problem?

How many times you have to ask the same question-if the transmission cooler can carry the load -best have the transmission checked out could be slipping causing the engine to overheat

Have you had the radiator cleaned , you may have a partial blockage in the core tubes restricting circulation, often not evident until a load like towing is applied.

mark (mhpautos)

02 ram 1500 4x4 overheating when ac is on. heater is not working. what are possible causes?