low operating temp
Postmaster
Joined: Apr 2009
Posts: 4,086
Likes: 1
From: Malahat/Cowichan Valley
with my new radiator, it barely moves from 190. When i installed my mechanical full sweep gauge i found out what the NORMAL letters mean. N is 190 on my truck. O is 215. etc etc. If your rig is not heating up, it is either stuck open thermostat or stuck open thermostat, between one of those two you will find the problem. Nothing else explains it and i mean nothing. Even if you fan was stuck in full on mode, it will still heat up. It has to heat up for the thermostat to open so even if the fan was sending a million CFM through the engine compartment it would still heat up because the water is inside the block. If it is not heating up the water pump has the ability to pump cold water onto the warm surfaces and cool them off to cool again and it just repeats. Thermostat is stuck open for sure. Change it out and see
Senior User
Joined: Jul 2009
Posts: 163
Likes: 0
hey guys sorry its been a while.....my truck hardly heats up as well I just installed NEW Motocraft thermostat, new waterpump, new ALL Aluminum radiator, and new fan clutch, the most it gets is to the O in NORMAL.
Senior User
Joined: Sep 2009
Posts: 110
Likes: 0
From: Cartersville Georgia
Apparently this problem is common. All I have is the factory gauge and my truck won't get past the "N", and thats after driving around for about 15 minutes. This is after recently replacing the thermostat, and blocking of about 1/2 of the radiator. Cab heat is okay, but I didn't flush out heater core when I changed the coolant. But even though the gauge doesn't get past the "N", after stopping, I can't hand hold any part of the radiator or the hose above the goose neck. So the motor is heating up, the gauge just isn't relaying it well.
This summer, I plan to add a digital temp gauge along with a boost gauge.....
This summer, I plan to add a digital temp gauge along with a boost gauge.....
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
The factory guages are junk from day one if it is on n or o you are probably in the 180 to 200 range. But like I said the heater will work if the water is 100 the problem is with the heater some where, is both your heater hoses hot.
Wreckinball the fan running all the time when temps are cold enough will keep them from heating. My fan locked up because of the high pressure on the ac one thanksgiving and even with a full insulated winterfront I could not get over 125 degrees unless I was on a serious mountain.
When it is real cold we have to sometimes idle up to as high as 1500 to keep the temps up in the 150 range and that is with a closed winterfront, so it all depends on the temps.
These motors don't build much heat when you are not using horsepower.
Wreckinball the fan running all the time when temps are cold enough will keep them from heating. My fan locked up because of the high pressure on the ac one thanksgiving and even with a full insulated winterfront I could not get over 125 degrees unless I was on a serious mountain.
When it is real cold we have to sometimes idle up to as high as 1500 to keep the temps up in the 150 range and that is with a closed winterfront, so it all depends on the temps.
These motors don't build much heat when you are not using horsepower.
Senior User
Joined: Sep 2009
Posts: 110
Likes: 0
From: Cartersville Georgia
The factory guages are junk from day one if it is on n or o you are probably in the 180 to 200 range. But like I said the heater will work if the water is 100 the problem is with the heater some where, is both your heater hoses hot.
Wreckinball the fan running all the time when temps are cold enough will keep them from heating. My fan locked up because of the high pressure on the ac one thanksgiving and even with a full insulated winterfront I could not get over 125 degrees unless I was on a serious mountain.
When it is real cold we have to sometimes idle up to as high as 1500 to keep the temps up in the 150 range and that is with a closed winterfront, so it all depends on the temps.
These motors don't build much heat when you are not using horsepower.
Wreckinball the fan running all the time when temps are cold enough will keep them from heating. My fan locked up because of the high pressure on the ac one thanksgiving and even with a full insulated winterfront I could not get over 125 degrees unless I was on a serious mountain.
When it is real cold we have to sometimes idle up to as high as 1500 to keep the temps up in the 150 range and that is with a closed winterfront, so it all depends on the temps.
These motors don't build much heat when you are not using horsepower.
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
It will always turn, it is supposed to have some resistance (kinda tight) they just are not turning the same speed as the motor. When one locks up it sounds like a plane taking off and it will usually be when you are pulling a load on a hill.
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