[SWINGRRRR]

My truck started over heating yesterday. The night before I noticed the heat wasn't blowing very hot, but didn't think anything of it. I checked the coolant the next day and it seemd fine. I'm not loosing any.
Well yesterday on the way to a BB game, my truck overheated. The gauge was in the red. I stopped, hosed the radiator down till it cooled and limped it home. I really don't think it a head gasket. I let it warm up and reved it up, no bubbles in the coolant tank. I am worried its the fan clutch. When I went fast, the temps came down. When I was idling at lights, its crept back up.

I can hear like a "tea kettle" bubbling over noise coming from my coolant cap.

Truck is an '02 4.7L

 

[Landman873]

i would also check your water pump and also could be like you said the fan clutch.

 

[Mudchucker]

A bad radiator cap will either leak, or not open, and collapse the upper rad hose when your truck cools.

Either waterpump or thermo,.. if you turn on the heater/fan and your temps go down,.. its not the waterpump.

 

[Landman873]

now that i thought about it for a min i was thinking thermostat but if it cool off when you go quicker sounds fan clutch to me see if a buddy will let you take his fan off and try it. i had to do this with a truck at work and ended up saving some money cause it was something else. Wait for some other smart guys to wake up. but i think they will confirm with me and mud here. grab it when its cool and see if it spins very easy should tell alot

 

[SWINGRRRR]

I don't think its the WP. While messing with it yesterday, the thermostat opened and alot of water was pumped out with the cap off. (Stupid I know) I was trying to "burp" it with the cap off.

Thanks guys. I just figured I would check. I don't wanna throw money at it and the new fan clutch not fix the problem.

I guess I should mention that the temps fluctuate. It will be in the red, then what I assume the thermo opens and the water changes positions. Then after running again for a minute, itll warn back up, and stay hot(gauge in the red.) I think the water in the radiator isn't being cooled. If that makes sense.

I haven't gotten the courage to grab the fan with it running yet. How hot does it need to be? I dont wanna run it a long time in case is seizes or something.

 

[SWINGRRRR]

Ok, now I'm stumped. I went out and let it idle for about 10 minutes. I turned the heat on and it took a long time to start feeling it in the cab. Anyway, once the temp gauge pegged out, I turned the truck off and moved the fan. I could spin it both ways.
I started the truck again, but I put my floor fan from my bedroom in front of the radiator. My temps still climbed, but it didn't peg out.


That should say without a doubt, its the fan right?

(I just don't wanna throw money at it. I'm getting married in 27 days, and I'm broke as a food stamp.)

 

[chad1972]

check for play in your fan,hold it in the 9 and 3 oclock pos.and wiggle it back and forth, if alot of play, possibly the wtr/pmp, spin it and it should not make more than 1 full rotation, if it does make 1-1/2-2 rotations freely, than poss. clutch. hope this helps.

 

[SWINGRRRR]

I just got back from the parts store. I took long stopless straightaways and the Check Gauges light only came on once. The temps were still high, but not bad. Once I got back home, I could hear the water bubbling in the upper radiator hose, and in the radiator itself.

I think regardless, Imma take it Wed and get them to flush and fill the coolant at Big 10.

They didnt have the spanner wrench to rent, so Imma try it with some vise grips.

 

[chad1972]

I just got back from the parts store. I took long stopless straightaways and the Check Gauges light only came on once. The temps were still high, but not bad. Once I got back home, I could hear the water bubbling in the upper radiator hose, and in the radiator itself.

I think regardless, Imma take it Wed and get them to flush and fill the coolant at Big 10.

They didnt have the spanner wrench to rent, so Imma try it with some vise grips.

I have used a 12" crescent wrench,hit it with rubber mallet. use some wd 40 or equivilant. to get clutch fan off.

 

[SWINGRRRR]

I have used a 12" crescent wrench,hit it with rubber mallet. use some wd 40 or equivilant. to get clutch fan off.

Getting it off wasnt really a problem. I thought itd be a PITA but after getting the vise grips settled it came right off.

Bad news though. The clutch didn't help. I test drove it around the block and same thing. The temps skyrocketed. I am wondering if its something in the readiator. When I came back the upper radiator hose is boiling. Its too hot to touch, the puke can puked and I can hear water boiling.
Now the strange thing. The lower radiator hose is cold to the touch. I can feel the larger spring in it.
Does anyone know if what the flow is like in the radiator? Does it go from top down or bottom up?

 

[chad1972]

the t-stat neck is at the bottom and holds the tstat, did you check the stat? I think the flow is still top to bottom

 

[SWINGRRRR]

Im grabbing some lunch to cool my temper right now.

I went back out there and re-checked. The hose is now slightly warm, but the other side of the stat, the block, is smoking hot. Maybe that's my answer right there. I really really wasn't wanting to open up the system, but I guess I have to.

(If anyone cares, the Hungry Man Rotisserie Chicken sucks.)

 

[chad1972]

lol, I know what you mean,I just installed my efan, everything possible got in the way of mounting the brackets, take a break, its not that bad swapping out the stat. remember if you have to add water use distilled, and burp the system. the 4.7 does not like trapped air. keep us updated.

 

[MikeHTally]

Sounds like the t-stat is stuck closed.

 

[1baddak]

Have you had your cap tested? You can run it by any rad. shop and get it tested. Also if you want to know if your stats not opening, fill up your rad let it run with the cap off and watch the water when it opens the water will circulate across the coils.If it gets hot and the water doesnt circulate it didnt open.

 

[SWINGRRRR]

Yeah. Good news and bad news. Have I ever mentioned how much I hate the feel of coolant on your skin? This is why I gave up the damn truck as a hobby and bought a reef tank!!!

Well I am boiling the stat right now to see if it opens. Also, more bad news. Behind the stat was a bunch of black plastic pieces. Please Please Please don't say that the WP impeller is black plastic. These pieces look like its a new break. There are sharp edges were whatever it is exploded.


Does anyone know if the WP impeller is black? And if its made of plastic?

 

[SWINGRRRR]

Have you had your cap tested? You can run it by any rad. shop and get it tested. Also if you want to know if your stats not opening, fill up your rad let it run with the cap off and watch the water when it opens the water will circulate across the coils.If it gets hot and the water doesnt circulate it didnt open.

'02 Dodge 4.7L. No way no how to look into the radiator.

 

[chad1972]

uh oh, I dont know if the water pump blades are plastic or not. I will try and find out. :dunno:

 

[SWINGRRRR]

Stats good. It opened right up. I think Im still going to go with a 180* anyway.

 

[chad1972]

I just checked my service man. I do not know about the plastic pieces. but the 4.7 cooling flows from bottom to top. if the parts store does not have a 180 stat ask for onr from a 99 dakota r/t the 360. thats what I had to do to get mine. let me know.