Dodge Dakota Radiator and Cooling Problems

moquelvog

I recently went on a long road trip. During that time my engine temp peaked at about 240 w/ no A/C. (norm being around 190-200) Red line is 260. The first thing I changed was the thermostat. Didn't change a thing. I am hesitant to change my water pump because (1) it looks like it would be difficult and (2), I am not losing any water. The pressure in my upper and lower hoses seem to be sufficient. The strange thing is that the faster I go, the hotter is gets. if I go over 70mph, the truck would red line for sure. (Common sense would say the faster I go- more air in the radiator- the cooler the engine.) Once I back down to around 40mph, the truck cools to about 210 rather quickly. At a loss for what might be the problem. Any help out there?

dustyk

Your symptom is typical of a clogged or bad radiator. Check the fins that are between the cooling tubes. Move your hand over each row. I think youy'll find some that are loose and can move between the tubes. If the fins are okay I would backflush the radiator.

Best regards,
Dusty

moquelvog

Thanks Dusty. Funny you sent that tonight... I just finished replacing my fan clutch and water pump today. (I also cleaned my radiator.) I haven't taken it out yet to see if it acts up again, but essentially I have a completely rebuilt cooling system so if it continues to get hot, Thanks again for the advice.

moquelvog

OK. So I almost rebuilt my entire cooling system, yet when I am stuck in traffic, idling, my temp goes up way beyond normal range. When I am moving, the temp goes back down. The radiator is the only thing I haven't replaced. Is that my suspect?

Omen

lsample

I noticed my dakota was heating up when I would idle for awhile. I checked the anti-freeze and found it to be low in the radiator. I could also smell the anti-freeze, like it was getting onto the manafold. I put anti-freeze in it and made sure the overflow was at the right capacity also. After I run it for awhile I could still smell the anti-freeze. I checked it again and found the radiator low again. The overflow was still at capacity. It appeared that the anti-freeze was going out the overflow tube and maybe splashing onto the engine. What would cause it to heat up like this. Could it be a bad radiator cap or what.

Thanks

Larry

celticredneck

My 4.7 liter Dakota 4x4 just started overheating yesterday. I replaced the thermostat and that seemed to cure the problem. I let it run at idle for 20 minutes after putting antifreeze into it(the type that says it is compatible with all others) and then drove it over 30 miles, including a couple of stops along the way, and the temperature stayed just below the center of the normal range. I did detect a slight odor of antifreeze just as I pulled into my driveway, but did not see anything leaking and decided the smell was due to spillage when replacing the thermostat. Last night, I started into town and it overheated big time. I pulled off the highway as quickly as possible, and checked under the hood. There was quite a bit of coolant on the drivers side of the engine, and very little on the passenger side. I sat for half an hour to allow it to cool off, then tried to start it. The engine would fire but not keep running.. I had it towed home. This morning I tried to start it and it starts and runs fine, but I didn't keep it running. I checked all of the hoses and couldn't find any holes. I am going to get more coolant and refill the system. Then I'll start it and see, firstly if it I can see anything leaking and secondly if it starts to run hot. It isn't like this was a gradual onset of a problem, so I don't think the radiator is clogged. The temperature has always ran at the center of the normal range until it overheated the first time. When I go and get collant, I might also buy a nre radiator cap, because there is quite a bit of coolant around the cap.

c32077

Hello all,

Just this morning I was going in to work and I noticed that the truck wasn't heating up inside as it normally would have. I looked at the temp gage and it was readin very low as if it hasn't been running. Then it just spiked like crazy into the red. My check gages light came on and I pulled over. I opened the hood to check for a problem but nothing seemed to be apparent. Then the hose on the passenger side burst at the bottom and started spraying coolant. My coolant level was fine. I waited about half an hour and drove it back home. The temp gage rose slowly this time but eventually back up into the red. When I got it home I let it sit for a while and checked the fluid level again. It was still good and it hadn't leaked very much in the driveway. When I was inspecting the hose I could feel something inside the hose at the bottom. Not sure what it is unless the thermostat for this truck is very odd shaped. It kind of felt like rod or something similar about pencil thin and about 4 or 5 inches long. Does anyone know what this is and if this could be my problem?

When I pulled over the first time. I walked to a parts store and grabbed a manual. It didn't seem to offer much help in troubleshooting. I figured I'd come here and see what you guys can do for me.

Thanks and I appreciate any help you can give.

Chuck

celticredneck

Well, you can tell from my first post, I am far from an expert, but my son and I did replace the thermostat on my Dakota and it looked like any other thermostat to me. I definitely didn't see a 5" rood sticking out into the hose. Your problem does sound like a sticking thermostat to me. Sounds as if it stuck wide open at first, then closed and stuck there. So far, since replacing lost coolant and getting a new radiator cap, my Dakota hasn't overheated again and I've driven it several hundred miles since then. I hope it remains so, because since my wife's 89 Jeep Cherokee failed inspection due to having a badly rusted out floor board, the Dakota is our only vehicle.

kenjwest

I have a 2004 Dodge Dakota Pickup and the temp gauge is running high but not overheating. My electrical cooling fan is not coming on - relay is okay, fuse is okay, and the fan is okay. The thermostat seems ok too. Any ideas what may be wrong? Is there another thermostat I should be looking at?

ahoover123

I am the original owner of this truck with 124,000 miles on it. It has been a fine truck with no regrets. However, back in December it ran really hot and cracked one head and warped the other. To make a long story short, both heads were replaced, water pump, thermostat (3 times), radiator and fan clutch all were replaced eventually since then. Also just replaced the catalytic converter the other day. It will still run past the center mark while on the interstate causing the electric fan to stay on, which is uncalled for at highway speeds, but the temp controls the fan so it comes on anyway. It will keep climbing a little more to around maybe 220 degrees. I stop on the side of the road and check the lower hose to see if the thermostat has opened and it has not yet opened which is the strangest thing in the world. The thermostat has been replaced 3 times and is 195 degrees. I have tested these in boiling water with 2 thermometers in the pot and they open at around 205 which is okay. Why in the world it will not open while in my truck while driving on the interstate is beyond me. There is nothing else that anyone can do even all the mechanics are scratching thier heads on this one. Does anybody have any ideas on what could be happening here? By the way, it runs at normal temp while doing city driving.

esper

I have 2001 quad cab having the exact same problems. I replace the water pump twice, thermostat 3 times a new fan clutch, new radiator cap, radiator flush and still overheats. I wanted to know if you ever figured out why and if you fixed it. Im at wits end. Help. PLEASE

moquelvog

I haven't actually. Since its been winter, I haven't had a need to look into it further, but as the season heats back up I am going to do the only left... change out the radiator. Do me a favor, if you do it first, please let me know if that works. I'll do the same if I end up changing it out first. Thanks.

Omen

aredtruck

Just this weekend I trucked to the top of Wolf Creek Pass in my 2001 4.7L Dakota. When I stepped out of my truck I could smell coolant immediately and it was my car leaking it. When I popped the hood it appeared that the coolant had been spewing from the overflow bottle. This is the first time I've ever had this problem and cannot seem to figure out exactly what it could be. My fist suspicion is that the radiator cap has gone bad and the pressure is now incorrect. Does this sound like the culprit?

So after that I drove it into town, topped it off with coolant and proceeded to drive home. After going back over the pass I stopped at a gas station and found the same problem of leaking coolant from the overflow bottle. Unsure of what to do I drove it back to Boulder without a problem. But as I pulled into my drive, coolant was leaking once again.

Any solutions?

Thanks

stsdakota

I,m having the exact same problem. Did you ever figure it out?

moquelvog

I have a 97 Dodge Dakota 5.2L with an ext transmission cooler. This apparently is rare and a new radiator will be upwards of $300. If I buy a radiator with an internal transmission cooler it is about $180. Can I do a conversion?

Omen

moquelvog

Nevermind my previous post. After doing some research, I found out why such a drastic price difference. I didn't know that a manual transmission like mine, does not require a cooler. Just one of those things you learn I guess. So I am forced to purchase a radiator with an ext cooler mount which is rare i.e. the higher price. Obviously I can't convert because there is no need for a trans cooler. With that said, anyone have a radiator they want to sell?

Omen

sportzno7

Can anyone tell me where the thermostat is located on a 2003 with a 4.7 engine?

dustyk

The engine coolant thermostat is located where the lower radiator hose connects to the engine. Its a much nicer job if the vehicle is on a hoist, but you need to remove the lower splash shield that's under the front of the engine. There are two bolts that secure the thermostat housing to the engine.

I would recommend using a factory gasket instead of those paper types commonly sold at auto parts stores. I apply a very thin film of RTV on the gasket before I install it, although I've never seen a leak on a factory installed one. The factory gasket appears to be a better grade of material. I use RTV because I use to own Chevies!!

Best regards,
Dusty

sportzno7

Thank you dustyk for the information. We got changed, so hopefully this will solve our problem. Have a great week.

jayzzzz1

I was going to flush the radiator on my 2000 4x4 Quad Cab 4.7 but for the life of me I can't find the drain any help.....

seventy7

The rad drain tube is located on the lower left portion of the rad (if you are sitting in the driver's seat). You may have to take off the plastic stone guard first.

See my old post for an overly-detailed description at:
http://townhall-talk.edmunds.com/direct/view/.ee99556/2478

hock72

I have coolant in the reservoir and coming out the overflow. Coolant is low in the engine and radiator. I have had the system pressure checked three times, replaced the supply and return hoses, thermostat, and cap. Thursday I had the system back flushed for the second time and coolant topped off and the reservoir filled the proper level. Today I checked the system and have no coolant in the supply hose and the reservoir is overflowing.
Does anybody have any ideas? Please. Radiator or Pump which one is it cause that’s all that’s left.

hock72

Forgot to add that its a 2002 4.7 V8

taylor7276

Hey dusty
I have the same problem with my dakota v-6 magnum. But I have radiator fluid leaking from what appears to be the housing for the thermostat. Could that be a freeze plug or is it probably the housing bolt rusted out? I appreciate your expertise!

Bill

dustyk

Bill,

My apologies but I've been away hunting and just got back yesterday.

Since you do not mention the year, but refer to your engine as a "Magnum," I'm gpoing to assume you have a 3.9. If there is any leaking from the thermostate housing I suspect a hair line crack or it is badly warpped. Replacing the housing should solve your problem.

Best regards,
Dusty

gman41

I have the same issue...how did you make out...what was it.

manamatt

heater barely blows warm air..never hot. have replaced thermostat, temp gauge reads same as before. coolant level always good, doesn't leek. any advice welcome.

moquelvog

I had the same problem on my 97 dakota. I read on here somewhere about a reverse flush of the heater core. If you look at a Haynes manual you will see two 3/8 hoses, one that flows into and one that flows out of your heater core. Notice the direction that it flows. (Mine flows from passenger to driver) Go to your local home garden center and pick up a replacement 3/8 female garden hose end. (This is so you can insert the 3/8 end in the radiator hose and the other end you can hook up to the garden hose.) Disconnect both radiator hoses at their first connection point before and after the heater core. Hook up the garden hose to the end of the radiator hose so that the flow is in the opposite direction that the coolant normally flows. (At this point I would recommend putting a bucket under the other side to catch all the liquid coming out.) Then just turn the garden on full blast for 5-10 mins. Then put everything back together again.

I did this and it worked great. I went from having little to no heat on a cold morning to having to turn the heater down because it was too hot. It still takes the truck getting to norm operating temp to get the heater that hot, but it does work.

Hope this helps.

Cheers,

Omen

DeLorean

1998 Dodge Dakota, 4-Cylinder, Stock

I recently noticed that during the cooling cycles the car goes through from going to ~210 down to ~185 (when the radiator fan is on), a significant amount of steam (I think) is produced from the radiator. I initially noticed this when I turned off my car and got out to see steam coming from the grill. It is not enough to see when the car is moving, but if the radiator fan is turned on at a stop light, you can see steam coming out from under the hood. The engine never overheats!

When I open the radiator cap, coolant is filled to the brim. The reservoir also indicates a sufficient amount of coolant. Oil level is slightly low, right on the "add" line.

Is this something I should be worried about? Again, the engine doesn't overheat.

Thank you.

dustyk

When you remove the radiator cap, is there adequate pressure?

If there is around 13 pounds of pressure and there is no signs of coolant loss, either from the radiator or the coolant expansion tank, you are probably experiencing steam from the collection of moisture under the hood or possibly snow, if you live in a snow climate. I wouldn't worry about it, but would monitor the expansion tank for signs of coolant level change when cold.

If there is little or no pressure released when the radiator cap is removed, the cap is likely defective. In this scenario the steam you see is probably hot coolant vapors being released. Over many cool down cycles you will notice coolant loss in the expansion tank. the fix is to replace the radiator cap.

Best regards,
Dusty

tommy97

I'd like to do a total cooling system flush on my '97 Dakota 2WD (V6/3.9L).

Should I just following the basic procedure suggested by the Prestone flush kit, in which you add water to an in-line Tee (hose going to heater core inlet) and open drain at the bottom radiator, etc.?

Or there a better way that requires - in addition - removal of one or more plugs in the engine block itself?

Any thoughts are appreciated.

dustyk

Tommy,

For low pressure flow flushing, the engine block drain plugs do not need to be removed, however, they will need to be removed to completely drain the engine of coolant.

If you are real fussy...or "anal" as my kids would say, you should use distilled water instead of tap water when replenishing the coolant. I know, this is not typically done, even at automotive repair centers and tap water is probably adequate for most vehicles within the expected lifetime of the cooling system parts. But tap water can contain minerals that may be corrosive to internal engine and cooling system parts. It depends, of course, on any particular water supply.

Best regards,
Dusty

tommy97

Thanks for your response, Dusty.

Your point about distilled vs. tap water is well taken, and one I'm well aware of. Tap water, while not ideal, is most practical.

When all's said & done, it sounds like the "upwelling" approach (forcing effluent up & out of the radiator fill port under pressure) is the best all-around way.

As a side curiosity, regarding the radiator drain plug, if a guy wanted to open it, is there any easy way to do so? I looked a couple times and it seems to be well hidden and disguised. Is there a special "hat trick" involved to access it?

dustyk

The best way to access the radiator drain plug is to remove the lower fan shroud. This is the black plastic cover that is located directly below the radiator and hides the lower radiator hose. I think the plug is plastic on your '97. Be careful, they can be broken!

Regards,
Dusty

tommy97

Thanks again, Dusty. The fan shroud is probably a "bear" to remove but your idea is along the lines of what I was afraid I might have to do.

On a final point, what was driving this whole thing was the sad circumstance in which a couple years ago I lost virtually all heating. My heater core is toast and this was no doubt due to my lame failure to ever flush my coolant. This even contributed to my water pump failing (bearings/seals) at about 8 years (57590 miles).

So - what to do about the clogged heater core? I'm sure you know what's involved in removing it from the Dakota so let's not even go there. In exploring/searching/surfing the 'net, I stumbled onto what I believe may be the very next best thing:

Thoro Flush by Irontite (Kwik-way):
http://www.irontite.com/store/index.php?main_page=product_info&cPath=1&products_- id=4&zenid=1ca29354381138950675c2b8b7603f95

According to its manufacturer, this industrial strength product has been successfully used on diesels and heavy duty trucks. The one-pint jar is actually a powder which is mixed on-site to the recommended specs (using very hot water). You then isolate the heater core by cutting/disconnecting the feeder hoses and circulating the Thoro Flush solution in a backflush direction for about 10 minutes or so. It's supposed to work miracles ...

This, my friend, may be the only "solution" to this problem, short of the miserable task of removing the core from under the dash.

What say you? Have you ever heard of/used Thoro Flush?

tommy97

A couple years ago I lost virtually all heating. My heater core is toast and this was no doubt due to my lame failure to ever flush my coolant. This even contributed to my water pump failing (bearings/seals) at about 8 years (57590 miles).

So - what to do about the clogged heater core? I'm sure many of you know what's involved in removing it from the Dakota so let's not even go there. In exploring/searching/surfing the 'net, I stumbled onto what I believe may be the very next best thing:

Thoro Flush by Irontite (Kwik-way):
http://www.irontite.com/store/index.php?main_page=product_info&products_id=4&zen- id=1ca29354381138950675c2b8b7603f95

According to its manufacturer, this industrial strength product has been successfully used on diesels and heavy duty trucks. The one-pint jar is actually a powder which is mixed on-site to the recommended specs (using very hot water). You then isolate the heater core by cutting/disconnecting the feeder hoses and - with the heater turned ON - circulating the Thoro Flush solution in a back flush direction for about 10 minutes or so. It's supposed to work miracles ...

This may be the only "solution" to this problem, short of the miserable task of removing the core from under the dash.

Has anyone ever heard of/used Thoro Flush?

dustyk

No, I've not heard of the product. However, the industry has used other cleaning-type products for a long time.

I worked in a radiator shop for a year and we typically backflushed heater cores and entire systems without using a chemical additive with good success. Occasionally some vehicles did need a cleanser.

Dodge used heater cores and air conditioning condensers and evaporators in their trucks from Harrison in the lates ninties and these were trouble prone.

Regards,
Dusty

tommy97

This is for the '97 Dakota Sport 2WD

Heater:
Does anybody know for a fact whether the control knob/key position actuates
a solenoid valve, etc. to allow hot water to flow/not flow thru the heater
core? Something inside me says there should be such a control. Otherwise,
when driving thru Death Valley in August, even though the AC is turned on,
hot water is circulating under the dash board! On the other hand, when I
recently isolated and flushed said heater core, I could find no such
position of control knob/ key position that seemed to prevent water from
circulating thru the core. In other words, once I got it flushed out, water
flowed through it no matter what the position of any knob/switches (and
whether the ignition key was on or removed).

Radiator drain valve:
Along with my heater core clogging, it turned out that the radiator drain
valve was also clogged - so much that nary a drop would drain out when
"opened". When I looked at the valve, the "rib" on the plastic knob was
vertical. It would only turn counterclockwise 1/4 of a turn, where it
seemed to hit a stop. I presume this horizontal position of the rib is the
open position. Does anybody know of a physical trick that can be done to
clear out the drain valve? I tried fishing a small wire up in the valve
opening (it's hard to get to), but no luck.

Any help is appreciated!

dustyk

Your observation is correct. Engine coolant circulates through the heater core at all times. Air flow through the heater core is controled by a mode door which directs air through the HVAC housing. Automakers at one time did use a flow control valve on the input side to cut-off the flow of coolant to the heater core. That design practice was abandoned in favor of the current manner, in part to reduce the number of components in the system, and also to remove an often troublesome, high failure part. When I did auto repair service full time, these control valves were a common source of leaks.

Be sure you've got the drain cock open all the way. The plastic drain cocks on Mopar radiators work real hard. I haven't run across one yet that has a clogged drain cock. I suspect you may not have the valve open all the way.

Regards,
Dusty

tommy97

Thanks for your reply, Dusty. Since posting this, I also managed to get confirmation from a couple Dodge truck service managers that - in the Dakota - there is no valve controlling the water flow thru the core. And as you said, earlier automobile models did have stop/diverter valves to prevent hot water from flowing thru the core in summer months. My dad's '63 Chevy pickup was exactly this way.

As for the radiator drain valve, I'm now 95% sure that I didn't open the valve correctly. After turning it 1/4 turn counterclockwise, I believe I'm supposed to then pull it out (using, for example, micro channel-locks). I didn't do this last step and so probably never got the valve in an OPEN state. In the near future, I plan to go thru all this again and - this time - try carefully pulling on the plastic valve cap to open it. How does that sound?

dustyk

Yeah, after I responded to you I thought maybe you weren't pulling on the drain cock. I think you might have to press inward slightly before pulling outwards.

Good luck,
Dusty

tommy97

Dusty,

Could I please ask one more "bonus" question?

Back to your earlier comment, supposing I was interested at some point in doing a "high pressure flush" - could you please tell me where I'd find the "freeze" plugs on the engine block? How many are there? Are they hard to find? One on each side? 1/4" NPT?

Any advice is appreciated.

seventy7

Check out an old post of mine to help find the freeze plug and radiator drain valve locations.
http://townhall-talk.edmunds.com/direct/view/.ee99556/2478

dustyk

You are asking about freeze plugs while referring to performing a pressure flush. Freeze plugs are are round disk-like pieces of steel that fit into various places on a engine block to fill holes that are required during the casting process.

I think what you are asking for are the drain plugs. There are two on a 4.7 motor, one on each side of the engine block about midway between the oil pan rail and the bottom edge of the cylinder head.

Regards,
Dusty

tommy97

Dusty - you are right: my bad. Soon after I posted my question, I realized I misspoke in referring to them as "freeze plugs". Of course, I meant the drain plugs.

Per seventy7's advice, I reviewed the post here:
http://townhall-talk.edmunds.com/direct/view/.ee99556/2478

Though the post involved a different truck (4.7L 4X4 vs. my 3.9L Dokota Sport), I was able to pick up on a couple useful things. Laying under my pickup, I readily spotted the 9/16" plug on the driver's side. This one is easy to get to - just the opposite of the arrangement seventy7 described for his 4X4.

On the passenger side of my Dakota, I didn't readily spot the plug. I may have to put it up on ramps and try to find it again after a bit of "attitude adjustment".

tommy97

This is a follow-on point to an earlier thread I started here:
http://townhall-talk.edmunds.com/direct/view/.f150267

This post is really informational only, and I decided to start a new one in order that it might be seen by those wanting to do an effective "High Pressure" coolant flush on their Dakota.

As revealed in the thread cited above, there are 2 drain plugs (9/16" hex heads) - one on each side of the block. The one on the driver's side is rather obvious - it sits just behind the water pump and is easy to get to. The other one was troublesome to find. After searching a while, I decided to presume symmetry to help me find it. With this in mind, the good news is that the plugs are symmetrical and the passenger-side plug also sits just behind the water pump.

That's where the good news ends.

To my complete dismay, 3/16" above the head of the passenger-side plug sits a large bracket for the right-side engine mount! The interference this creates requires that the engine mount be removed before this plug can be removed. (Of course, no one in their right mind would do that.) I was so astounded by this that I actually took closeup digital pictures to convince any disbelievers. Unfortunately, this otherwise great posting template does not accommodate uploading of pictures, so you'll have to take my word for it. Bottom line: for all practical purposes, one one of the 2 drain plugs in the engine block (driver's side only) can be removed for a good coolant flush.

Whenever I see something like this, I get philosophical. I start thinking things like - the Dodge engine designers and the chassis designers work in 2 different buildings - never talk to each other and never know each other. It also confirms a thought I've had for many years: the aforementioned highly-paid mechanical engineers never actually do maintenance on the vehicles themselves.

aleyat

I need to replace it, I know, do I need to change the thermostat too? Are there other compatable years?? I can't afford a new one so I'm searching the local junkyards. . . . any sudgestions??? :sick:

dustyk

You should not need to replace the thermostate, unless the radiator cracked from overheating.

Have you tried an aftermarket radiator for price? I wouldn't advise a used one unless it was nearly pristine.

Regards,
Dusty

sledhead26

I have a 2001 dakota sport with 4.7 V8. It over heated about 3 weeks ago after replacing the thermostat I thought the problem was gone. Until 2 days ago it over heated again! This time I replaced the radiator cap. Drove it for about a half hour everything seemed ok. Drove it to work the next day no problems. Got home from work and I could hear the overflow bubbling sounded like boiling water. The only thing is the coolant was cold in the tank. So after calling a local dodge dealer the service manager told me he is 99% sure that I blew a head gasket. So I checked the oil and found no water, I even pulled all the plugs to see it one was wet with antifreeze found nothing! There is no white smoke coming from my exhaust either. So now I am stumped!!! Any help would be much appreciated.

engineer_andy

:confuse: Ok, I'm at a loss. My truck started overheating about a month ago... I have replaced the thermostat, heat temp sensor and bad hoses but it is still overheating. I checked the water pump (did not take it off) and it looked fine. There was no wiggle and nothing coming out of the weep holes plus with the top radiator hose off i started the truck and fluid gushed out everywhere. Then I took out the thermostat to see how it ran without one, no change... So not a bad thermostat, temp sensor or water pump. When I took the thermostat out there was no fluid in the block and my radiator was full.............. Please help WHAT IS WRONG WITH MY TRUCK. AND WHY IS IT OVERHEATING I am usually very good at finding the problem and fixing it but this I can't figure out.

moquelvog

I had the same thing happen to me on my 97 dakota. I replaced EVERYTHING in the cooling system except the radiator. Guess what it was... the radiator. Same thing you described... radiator seemed to work fine. I even tried flushing it first. Guess it just had a bad core. Put a new one in and temp was perfect and no problems since. Hope this helps.

Omen