Should my coolant temp gauge needle rest on left peg when engine off?

[bigceltic]

I noticed that when my truck is off (key removed) the indicator needle on my coolant temp gauge does not rest on the left peg (seems to be hovering a couple of mm's above the peg). Is this normal?



2006 Ram 2500 Mega Cab 5. 9L

 

[goodguys75]

dont think so, mine goes all the way down.....

 

[mfurrh55]

Should go all the way down, mine does, Monte

 

[rbattelle]

I just went out and looked at mine. All the needles are resting on their pegs.

However, in the right light, and looking from just the right angle, I can see where they might appear to not be resting on the peg. I think the needles are tapered slightly front-to-back.

-Ryan

 

[C.Solomon]

My 06 doesn't rest on the peg, never has. I was always wondering about that.

 

[bigceltic]

After reading the responses, I said to myself "Self, you better look again". I did, and I was wrong. When the key is not in the ignition, it does rest on the peg. I realized I was thinking more of when I turn ignition on (not started) and the needle jumps to just below the first mark on the gauge. As soon as I start it (in the morning, so the truck has been sitting all night) it seems that it is above the peg (I felt it should stay on the peg until it has warmed up).

Bottom line is I am trying to figure out the changes in my truck's coolant "habits" - the temp gauge used to always sit at about the 190 deg mark and only hit the 200 line when working hard (say towing my trailer up a hill) and then quickly drop back down to 190. I noticed that in the last year, it seemed to remain on the 200 mark, and then jump to, say 210, and then back to 200. I red in one of the recent issues of the TDR mag that the thermostat may the the prob, so I replaced it with a new one (190) from the local cummins distributor. I seemed to help a bit but the temp still seems to stay at or near 200 for long periods (has not gone above 200, so that is a positive). I was thinking that maybe my engine temp gauge was not reading correctly. Could it just be the thermostat? Should I just not worry and move on? I kinda wanted to go back to how it used to be with the "normal" temp being 190 or so and the occasional move to 200.

 

[cerberusiam]

The temp gauge sitting at 200 when you are working it hard is normal. Mine has always run right at or half a needle over 200 when really working the truck, Then, run several needles width under 200 when not working. The gauge is not real so as long as the it is consistent in its actions with no bovious coolant loss it is likely fine.

 

[bigceltic]

The temp gauge sitting at 200 when you are working it hard is normal. Mine has always run right at or half a needle over 200 when really working the truck, Then, run several needles width under 200 when not working. The gauge is not real so as long as the it is consistent in its actions with no bovious coolant loss it is likely fine.

Thanks. It is definitely consistent so I will leave well enough alone.

 

[rbattelle]

I swear that over time my coolant has been running warmer. Unloaded during a hot summer day running up a long grade I can hit 200°, and I always think, "what if I were towing a heavy load?"

I still haven't decided whether it's a problem or not. By experimentation I've learned that the A/C has a big effect on the engine peak temperature. A couple years ago on two consecutive days I drove home at the same speed (70 mph) in the same weather conditions (hot, sunny summer afternoon, temperature near 80°F, moderate wind) on nearly-flat highway.

On the first day I used the A/C to cool the cab and reached a peak temperature of 196°F.
On the second day I left the A/C off and reached a peak temperature of 189°F.

Not a scientific test, but it certainly suggests that heat flowing back into the radiator from the A/C condenser has a significant impact.

Don't worry too much anyway. These are all-iron engines, and can take quite a bit of heat before anything bad happens. I don't think 210 or even 220 is a problem.

-Ryan

 

[goodguys75]

After reading the responses, I said to myself "Self, you better look again". I did, and I was wrong. When the key is not in the ignition, it does rest on the peg. I realized I was thinking more of when I turn ignition on (not started) and the needle jumps to just below the first mark on the gauge. As soon as I start it (in the morning, so the truck has been sitting all night) it seems that it is above the peg (I felt it should stay on the peg until it has warmed up).

Bottom line is I am trying to figure out the changes in my truck's coolant "habits" - the temp gauge used to always sit at about the 190 deg mark and only hit the 200 line when working hard (say towing my trailer up a hill) and then quickly drop back down to 190. I noticed that in the last year, it seemed to remain on the 200 mark, and then jump to, say 210, and then back to 200. I red in one of the recent issues of the TDR mag that the thermostat may the the prob, so I replaced it with a new one (190) from the local cummins distributor. I seemed to help a bit but the temp still seems to stay at or near 200 for long periods (has not gone above 200, so that is a positive). I was thinking that maybe my engine temp gauge was not reading correctly. Could it just be the thermostat? Should I just not worry and move on? I kinda wanted to go back to how it used to be with the "normal" temp being 190 or so and the occasional move to 200.

get a scan gauge 2 and you can read your coolant temp... . that is why i have it...

 

[Shadrach]

I never liked the way the factory coolant and oil gauges "work" so I added a second pair on my pillar. My factory gauges are Metric and my Isspros are in English. Being Canadian I am bilingual Shad