Author Topic: No Heat  (Read 10187 times)

Offline Tazman

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No Heat
« on: December 30, 2015, 02:58:26 pm »
I drive 14 miles one way to work never going over 45 miles per hour. I usually do not complain about the cold but I must be getting soft as I get older. My truck does not get warm enough to get any heat from the heater. I have an 180 degree thermostat coupled with a aluminum radiator. Any ideas?
Thanks
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Online bd

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Re: No Heat
« Reply #1 on: December 30, 2015, 04:34:20 pm »
Grass roots approach on where to begin:

First and foremost, is the cooling system full of coolant?

180° is pretty hot!  Does the upper radiator hose become too hot to touch with a bare hand?  It should.  If not, perhaps the T-stat is stuck open or missing.

Does the radiator get too hot to touch with a bare hand?  Typically, they do.  If not, the T-stat maybe stuck open/missing, or there maybe way too much air flowing across the radiator, or the radiator is simply too big for the application.  If the radiator is too big for winter use, but you need extra cooling during the Summer, you might consider an adjustable winter front and/or installing a 195° thermostat.  If you are running a solid fan, consider swapping to a standard fan with fewer blades or convert to a standard-duty fan clutch and fan.

Do the heater hoses get at least as hot as the upper radiator hose?  They should.  If not, you might have incorrectly routed heater hoses and/or a restricted heater core.  The heater core is plumbed directly off of the engine, so the coolant passing through the heater core will be the same temperature as the engine, which should be very close in temperature to the rating of the T-stat.

Is the heater ducting open and clear of debris for unobstructed airflow (e.g., no mice middens, rags, etc)?  Is the blend/temperature door connected through its cable to the temperature control and properly adjusted so that air is, in fact, blowing across the heater core and not bypassing?

Rich
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In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Offline jg1977c20

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Re: No Heat
« Reply #2 on: December 30, 2015, 07:04:54 pm »
my first thought would be change the thermostat - its probably stuck open - either you have a " fail-safe " one in their or got lucky and she failed open - regular t-stats 99% of the time fail closed and you boil over ( letting the engine cool down and removing the t-stat would get you to a parts store in that case )  in any case ask for a "fail-safe" one they are woth the couple extra bucks .
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Offline Tazman

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Re: No Heat
« Reply #3 on: December 31, 2015, 09:20:51 am »
The radiator is full and I did check the fuse which is fine. I will check the hoses next but this morning(12:30 am) when getting home I made it a point to look at the temp gage. It showed it being about 125 degrees, this after driving 14 miles at 45 mph when it was about 34 degrees outside. Should it not be higher than that?
Thanks,
Proud of and proud to be a veteran of our military.
God BLESS AMERICA

Online bd

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Re: No Heat
« Reply #4 on: December 31, 2015, 04:22:08 pm »
So, you had about a 20-minute drive with a 91° F change (or roughly 5°/min rise in engine temperature at 34° F ambient).  That's a little lethargic warming up.  How hot will the engine become if allowed to stabilize at operating temperature?  Does it actually ever reach 180°?  You may have a simple thermostat issue.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline blazer74

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Re: No Heat
« Reply #5 on: December 31, 2015, 06:12:55 pm »
Aluminum rad and 180 t stat. I had the same and not enough heat.
192 t stat makes a big difference.

Other wise I agree probably  a stuck open t stat

Offline Stewart G Griffin

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Re: No Heat
« Reply #6 on: January 01, 2016, 09:24:48 am »
How cold is it?

i noticed here, when it gets really cold, it may take up to a 1/2 drive time to get warm inside irregardless of how well the heater works.

Offline Tazman

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Re: No Heat
« Reply #7 on: January 01, 2016, 10:08:12 am »
Mid thirties at the lowest. Like I said this never used to bother me .
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Offline fitz

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Re: No Heat
« Reply #8 on: January 02, 2016, 05:36:19 am »
Was the aluminum radiator in the truck last winter?
Has any parts of the cooling system been changed since last winter?

Offline impco lpg

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Re: No Heat
« Reply #9 on: January 03, 2016, 04:56:28 am »
get rid of the viscose fan, and fit twin 12v fans made a big difference for me
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Offline Stewart G Griffin

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Re: No Heat
« Reply #10 on: January 03, 2016, 08:10:35 am »
The radiator is full and I did check the fuse which is fine. I will check the hoses next but this morning(12:30 am) when getting home I made it a point to look at the temp gage. It showed it being about 125 degrees, this after driving 14 miles at 45 mph when it was about 34 degrees outside. Should it not be higher than that?
Thanks,

Yes, i think it should be at regular operating temp after 20 mins.  So, probably a thermostat issue.  But why run a 180 thermostat in winter?

Offline Tazman

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Re: No Heat
« Reply #11 on: January 18, 2016, 12:38:54 pm »
Finally got around to changing the thermostat, found something I have never seen before. The thermostat was stuck open no idea why but there it was. Changed it and all is well. 
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Offline zieg85

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Re: No Heat
« Reply #12 on: January 18, 2016, 12:43:42 pm »
I love a happy ending
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