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97 Blazer - No Heat


stcolympia
12-27-2008, 10:55 AM
I have a 1997 Blazer that was purchased approx. 8 months ago. The heat has not worked since I bought it. Not sure when it stopped working for previous owner. AC works well (if that matters at all). I would really like to avoid having to take it in to get fixed if at all possible, so if anyone has any suggestions that would be great! Also, please be descriptive as I am no mechanic by an stretch. Thank you!

MT-2500
12-27-2008, 02:35 PM
Make sure engine rad coolant is full.
Make sure engine tempt is getting up to 195 degrees.
Make sure heater control hot to cold actuater is woring from cold to hot position.
Feel both heater hose for being warm or hot to the touch.
Heater core could be stopping up.
Pull return heater hose and see if coolant is pumping threw heater core.
Ifr not try blowing air or water threw the heater coree.
Sometimes a back flush or reversing heater hoses help clean it.

In a real bad case the heater core will need replaced.

Ther should be some how to's up in the S-10 forum.
Good luck

stcolympia
12-28-2008, 07:22 AM
If my temp is not getting to 195 (currently only getting to about 160), is that a major problem? Or could it be due to the blockage in the heater hose?

MT-2500
12-28-2008, 09:06 AM
If my temp is not getting to 195 (currently only getting to about 160), is that a major problem? Or could it be due to the blockage in the heater hose?

160 does not give much heat.
Get a new 195 stat in it and see what it does.
Let us know if that helps.
Good luck

99avenger2.5
12-28-2008, 09:30 AM
if you are only getting 160 you will need to get a thermostat however 160 will still give you some heat. if you have no heat you probably have a blocked heater core. to fix that you can remove both heater hoses at the firewall and apply a little air pressure to one of the hoses or you can take it somewhere and get it back flushed.

stcolympia
12-28-2008, 12:23 PM
if you are only getting 160 you will need to get a thermostat however 160 will still give you some heat. if you have no heat you probably have a blocked heater core. to fix that you can remove both heater hoses at the firewall and apply a little air pressure to one of the hoses or you can take it somewhere and get it back flushed.

Yes I do have "some" heat, but on very cold days it's not much help...it definately blows out warmer than outside temp or "room temp". So a new thermostat sounds like the fix to me. I will try and replace it tomorrow. Does this website have a "how to" to replace thermostats? Also, what I am looking at $$ wise for the part? Hope it isn't all that difficult.

MT-2500
12-28-2008, 04:04 PM
Yes I do have "some" heat, but on very cold days it's not much help...it definately blows out warmer than outside temp or "room temp". So a new thermostat sounds like the fix to me. I will try and replace it tomorrow. Does this website have a "how to" to replace thermostats? Also, what I am looking at $$ wise for the part? Hope it isn't all that difficult.


How to are in the S-10 forum.

10 USA bucks can go a long way on a good stat.
Gates has a extra good no fail stat that sticks open if it goes bad and does not burn up engine.

Newer stats have a rubber sealing ring instead of a flat gasket.
Install stat like the old one came out.
Thermo bulb towards engine.
Also sometime you need to bleed air at a hose on upper intake area intake or heater hose.
Good Luck

stcolympia
12-29-2008, 05:14 PM
Well first of all thanks a lot for posting replies/suggestions on my situation, I really appreciate it. I replaced the thermostat earlier today w/ a 195 one. Initially the temp rose to about 200 and the heat was blowing hot. This lasted for about 3mins. After 3mins the temp dropped to around 170 and jumped up and down between 170 and 200 for a period of about of 10mins then finally stayed at 170 for good where it has been since. the 170 is better than what I was getting before and the heat is a bit better, but it is still not where it should be. Any ideas from the symptoms I described?

stcolympia
12-29-2008, 05:14 PM
Well first of all thanks a lot for posting replies/suggestions on my situation, I really appreciate it. I replaced the thermostat earlier today w/ a 195 one. Initially the temp rose to about 200 and the heat was blowing hot. This lasted for about 3mins. After 3mins the temp dropped to around 170 and jumped up and down between 170 and 200 for a period of about of 10mins then finally stayed at 170 for good where it has been since. the 170 is better than what I was getting before and the heat is a bit better, but it is still not where it should be. Any ideas from the symptoms I described?

MT-2500
12-29-2008, 06:14 PM
Better try another stat and bleed air out of heater core at hoses and recheck coolant in rad.
And make sure the tempt gauge is reading right.

A good 195 stat should hold the tempt at 195 degrees.

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