DODGE RAM FORUM - Ram Forums and Owners Club! - Dodge Truck Forum

DODGE RAM FORUM - Ram Forums and Owners Club! - Dodge Truck Forum (http://www.ramforumz.com/index.php)
-   4.7L PowerTech V8 Specific Topics (http://www.ramforumz.com/forumdisplay.php?f=205)
-   -   Yet another temp gauge question (http://www.ramforumz.com/showthread.php?t=93111)

snookomatic 09-29-2011 05:03 PM

Yet another temp gauge question
 
1 Attachment(s)
Hello!

I have a 2005 1500 4x4 4.7 Quad Cab with 92,500 miles. It was running hot - see picture, - not overheating, just running what I thought was hot. I had the T-stat replaced (To get totally up to speed you may want to read this first: http://www.ramforumz.com/showthread.php?t=92046 ) and coolant flushed and now the gauge reads straight up and down, where it should be according to 95% of the people and mechanics I speak with.

Here is the question: After I have been running the car for a bit and I stop to grab a soda or something when I start the car, from time to time and depending how long I have been letting the truck sit, the temp needle will climb to about "1-2 needle widths" (see picture) past center for a brief moment maybe 10-20 seconds or until I drive off then it goes right back to straight up and down. Seems sort of weird, just wondering if y'all have experienced this or if it is normal.

Thanks! - Ty

erm 09-29-2011 05:18 PM

That's normal. The vehicle has hot coolant, has been sitting with no airflow across the radiator and no coolant being circulated. That condition results in a slight temp creep. As long as it goes back down after you start moving again, yer good.

erm 09-29-2011 05:19 PM

Also, what's the condition of the finned surface and internal surfaces of your radiator? A good flush will always help.

SuperiorStyles 09-30-2011 07:37 AM

Start with the Fan Clutch it has alot to do with the cooling also change your radiator cap.
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.


  1. Drill a 3.18 mm (1/8-inch) diameter hole in the top center of the fan shroud.
  2. 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.
  3. 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.
  4. 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.
  5. 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.


  1. 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.
  1. 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.

snookomatic 10-31-2011 03:18 PM

Thanks for the info! Would a bad fan clutch be responsible for running hot at highway speeds?

SuperiorStyles 10-31-2011 07:48 PM

1 Attachment(s)
At Highway the Fan is being used 30 to 45% not much cause the Airflow of the wind coming thru. At low Speeds the fan should be Heard spining loud like if you had it direct without a Clutch. Change the Thermostat to a Jet Performance 180 degree and you will be happy with the Performance and Temp. Before all do a Flush and clean your Radiator Fins in the Opposite Direction of Air Flow. After my Change from 190 thermostat to Jet Performance 180 thermostat my Temp has always stayed at 193 degree. That's very good for being in Miami @ Temps of 98 degrees everyday outside.
Before the 180 thermostat I used to be always at 210 to 218 on street and Highway and with all new Cooling system.

Attachment 23013

02Ram4x4 10-31-2011 09:55 PM

my temp gauge does the same, but always goes back to normal just a bit below dead center, like posted earlier as long as it goes down and doesnt rise again everything should be fine!!!


All times are GMT -4. The time now is 08:21 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
vB.Sponsors
= Copyright RamForumZ.com a Gigathreads.com Network Site =Ad Management by RedTyger