Mild Overheating

[Eggo]

Hi, i’ve had my 73 satellite for just over 3 years now. it has run very consistently temperature wise in that it always sits with the needle on the left line of the U shaped section between the C and H marks (hope that makes sense). Recently it’s been creeping up above this which is really out of character for it and it seems to creep up more when i put my foot down a bit. I’ve changed the water pump as think this was leaking a bit and have changed the thermostat yesterday. The thermostat i put in was a 160. Have just taken it for a test drive and it seems to be getting hotter even quicker now which is really weird. Why could this be? the rad doesn’t appear to be leaking as the level doesnt ever go down really. Have included a photo of where it was sitting when i got home and this was with the electric fans on which normally cool it down really well. When i was driving back the needle was higher than what it is now. Not sure if maybe it could be the gauge playing up so guess i should get one of those gun type temperature readers (technical term lol) and have a go with that just to double check?

The weather over in the UK at the moment isn’t that warm either, i took it 300 miles down south a couple of weekends ago and it was maybe 15 degrees max and it was doing it then as well. Have dailyed it 3 years through some 30 degree summers and it’s never overheated or really shifted from where it usually sits. It doesn’t have a fan attached to the block but just the electric fans. They’re definitely on and working as i wired it to a switch in the cab so i put them on manually. Usually i only need to turn them on when going slowly round town and in traffic but recently they’ve been on constantly, even on the motorway, and the temp gauge has still been creeping up.

I definitely need a more accurate temperature gauge, have got a moon eyes one sat in the car but the place where it should attach in the engine block the thread is messed up further down so i can’t fit it

 

[Mopar Hunter]

i should get one of those gun type temperature readers (technical term lol)

You’re talking about an infrared thermometer gun. I would get one, your dash gauge might be off.

 

[davek]

Run a mechanical gauge and go from there. JMO

 

[Rusty knuckles]

Getting a lower temp thermostat and getting higher engine temps to me points to inefficient cooling from the radiator. You might be getting some buildup inside or lots of bugs or dirt between the fins. Do you have AC? Pretty easy for junk to get packed in between the radiator and condenser.

Edit to add, have you checked your timing on the engine? Possible it's creeping?

 

[Don Frelier]

I would check the radiator.
Have you changed the coolant periodically?
Like every 3 years or so.
Has the block been flushed.
160 is really too low. They were designed to run at 180 or 190. You actually get more wear runnying too cold.

 

[Eggo]

You’re talking about an infrared thermometer gun. I would get one, your dash gauge might be off.

thank you have ordered one will see what it says when it turns up tomorrow

 

[Eggo]

Getting a lower temp thermostat and getting higher engine temps to me points to inefficient cooling from the radiator. You might be getting some buildup inside or lots of bugs or dirt between the fins. Do you have AC? Pretty easy for junk to get packed in between the radiator and condenser.

Edit to add, have you checked your timing on the engine? Possible it's creeping?

i have AC but it’s not connected. the timing was massively out recently but sorted that just over a month ago. had to advance it quite a lot and did probably 1000-1500 miles with no issues before this problem started. thought it might be that when it first did it so checked the timing again but it hadn’t moved at all

 

[Eggo]

I would check the radiator.
Have you changed the coolant periodically?
Like every 3 years or so.
Has the block been flushed.
160 is really too low. They were designed to run at 180 or 190. You actually get more wear runnying too cold.

i’ve changed the coolant a few times recently - once at the end of last year before the issues started and now again so i could change the water pump. ok thank you i didn’t realise that, will get a 180 one. i thought the issue was the pump as i took it on a journey a few weeks ago and it was reading super hot on the gauge - the needle was 1/4 of the way across but when i let it cool down and checked it it hadn’t lost any water which seemed weird. however when ive changed the coolant it’s come out of the bottom of the rad no problems. i guess maybe it could be a bit blocked up anyway though ?

 

[sam dupont]

My Internationals seem to run warmer every year until I flush them. In a year's time, it will move a needle thickness. After flushing, the needle returns to the proper place and the process begins again.

 

[eldubb440]

did it have a higher thermostat and you changed it?

possibly the 160 thermo is opening at 160 and cannot close........ resulting in the coolant not staying in the radiator long enough to cool......... if this is the case, put a 190 in it and see what happens

I've actually lived this

 

[R413]

A plugged radiator means it won't transfer heat from air to coolant, not that the water won't move through it. It will look normal when opening the lower hose and letting the liquid go through it.

This product works great.

Summit Racing SUM-TC001 Summit Racing™ EVAPO-RUST THERMOCURE | Summit Racing

 

[Eggo]

My Internationals seem to run warmer every year until I flush them. In a year's time, it will move a needle thickness. After flushing, the needle returns to the proper place and the process begins again.

the thing with mine is it runs warmer when i put my foot down, when i don’t have my foot on the throttle at all the fans help the temp creep back down again

 

[Eggo]

did it have a higher thermostat and you changed it?

possibly the 160 thermo is opening at 160 and cannot close........ resulting in the coolant not staying in the radiator long enough to cool......... if this is the case, put a 190 in it and see what happens

I've actually lived this

i’m not sure which it had on before as never changed it before, will get a 190 and have a go though thank you.

 

[Eggo]

A plugged radiator means it won't transfer heat from air to coolant, not that the water won't move through it. It will look normal when opening the lower hose and letting the liquid go through it.

This product works great.

Summit Racing SUM-TC001 Summit Racing™ EVAPO-RUST THERMOCURE | Summit Racing

will give that a go thank you!

 

[1967coronet]

Water pump belt slipping when getting on the throttle ?

 

[RJRENTON]

did it have a higher thermostat and you changed it?

possibly the 160 thermo is opening at 160 and cannot close........ resulting in the coolant not staying in the radiator long enough to cool......... if this is the case, put a 190 in it and see what happens

I've actually lived this

I'll be conducting a clsss in automotive cooling system thermodynamics as to how the system functions relating to the heat gain (in the engine) and heat loss in the radiator (heat exchanger) and how the circulated coolant volume, and it's circulated velocity and specific heat characteristics of the coolant used interact. The assumed myth that the coolant must move slowly thru the heat exchanger is simply not ttue. And the t-stats function controls the minimum temperature of the coolant. What time is best for everyone??? BTW.... is mild over heating akin to being a little pregnant. Let's see some actual temperature readings (in degrees F) and volumes in gallons/minute (numbers) not just suppositions or uncalibrated instrument panel gauge readings.
BOB RENTON

 

[JedIEG]

I have nearly the same issue happening on my 72 this past week. My gauge usually sat on C and only ever crept up once while driving in 100°/38° heat with the AC on. This week it was hovering over H driving in the rain at 65°/18°.
The infrared thermometer is a great tool. I wasn't sure to trust the stock gauge, but when I stot the radiator the top tank was over 200F and the bottom at 150. The gauge wasn't lying .

 

[steve340]

It sounds like you need to get the radiator out and get it to a good shop.

 

[Eggo]

Water pump belt slipping when getting on the throttle ?

I replaced the belt at the same time as the water pump. Drove it to work and back the day after, about 20 miles each way, and it had no issues on the way there and on the way back the temps were creeping up slightly on the way home and had to have the fans on. Then changed the thermostat and took it on a 4 mile round trip and it was the worst its been lol. writing it like that has made me wonder if maybe actually it is the thermostat being too low at 160

 

[Eggo]

I'll be conducting a clsss in automotive cooling system thermodynamics as to how the system functions relating to the heat gain (in the engine) and heat loss in the radiator (heat exchanger) and how the circulated coolant volume, and it's circulated velocity and specific heat characteristics of the coolant used interact. The assumed myth that the coolant must move slowly thru the heat exchanger is simply not ttue. And the t-stats function controls the minimum temperature of the coolant. What time is best for everyone??? BTW.... is mild over heating akin to being a little pregnant. Let's see some actual temperature readings (in degrees F) and volumes in gallons/minute (numbers) not just suppositions or uncalibrated instrument panel gauge readings.
BOB RENTON

have an infared thermometer turning up today so will test it and see what the temps are reading as