No heat

[Brandon Samson]

I have a 1989 nissan maxima i put a new radiator
And a new thermostat and flushed the cooling system
And i have no heat but everthing flows correctly and their
Isnt any air in the system anyone know what im missing
And why i have no heat its cold and not fun

Topic

[Tom]

Usually, when there are new components in the cooling system, even when the person who did the work swears that there is no air in the system, the first thing I suspect when there is no heat is an air pocket trapped in the cooling system. How did you go about getting the air out?

Have you tried doing it this way:

If you have gone through that process, and are 100% absolutely certain there is no trapped air, there is often a valve in one of the heater hoses that opens and closes as you adjust the heat. You could check that valve for proper operation.

If that checks out as well, then it might be time to dig into the air blend doors in the heater box.

[Kevin Criswell]

[quote=”Samson97″ post=84922]I have a 1989 nissan maxima i put a new radiator
And a new thermostat and flushed the cooling system
And i have no heat but everthing flows correctly and their
Isnt any air in the system anyone know what im missing
And why i have no heat its cold and not fun[/quote]

You still have air in the system. There should be a bolt in the intake manifold that you need to remove to vent the air. The bolt should be next to the PCV valve.

See the gold colored bolt with the label next to it? That should be your air bleed bolt.

I found this on a different site.

First, check your coolant level to make sure it’s not low. You can do so by looking at the plastic expansion (overflow) tank and by opening the radiator cap (when cold) and taking a peek inside the radiator.

Also remove the air bleeder bolt when you remove the radiator cap.

See the bolt that is on the top on the intake manifold in the pic (look towards the lower right near a bunch of hose connections)? It’s the small bolt next to the sticker that reads NEVER OPEN WHEN HOT. That is your air bleeder bolt.

If you are low, then add coolant/water mix with both the radiator & the bleeder open. After it’s full, close them. Also, make sure the expansion tank is up to the MAX line with coolant/water mix as well.

Run the engine at 2000 RPM for a minute or two. Turn the heater on as well. Shut off. Make sure radiator is cool, then check the coolant level again. Add coolant/water mix if necessary. Run the engine again, heater on, shut off, make sure it’s cool, then check again…

I’ve opened up the cooling system on this car several times, and this is all that was required to get the air out. When I had air in the system, I could actually hear the water flowing into the heater core from inside the car.

Drive it and see how your heat is. If you still don’t have much heat, it is most likely the thermostat.

Attachments:

• nissan_maxima_rear_right_side_engine.jpg

[Brandon Samson]

Thanks i havent messed with the bleed screw yet i will
Try this some time tomorrow and hopefully it works if not
Then what and the thing the stops fluid from the heater core
Is open

[Tom]

If the coolant valve is open, there really are only two other possibilities . .. air in the system, or the blend doors in your air box are stuck and constantly feeding you cold outside air instead of passing it through the heater core. I would put my money on air though.

[Brandon Samson]

alright thanks

[Trent “Teddy” Martin]

You either have air within the system which yes I know was mentioned 400xs above or your heater tap has fallen apart when the pressure of the cooling system has been restored after installing then new parts and bleeding it

[Julian]

I think last week someone had a similar problem here after putting in a new radiator. In the end, the issue was that the radiator came with some sort of a plug where the hoses connect that needed to be removed 🙂

http://ericthecarguy.com/kunena/8-Service-and-Repair-Questions-Answered-Here/48807-2007-ridgeline-overheating?start=20

[Tom]

Yes, you are right on that, but their problem was with overheating, not just a lack of heat. I would say if the engine is able to operate under normal conditions without overheating we can safely rule that out as a suspect.

[Brandon Samson]

where would a heater tap be located and blend doors

[EricTheCarGuy]

Air in the cooling system. Be sure to watch the video. The bleed screw is really only there to make filling the system easier, it’s not necessarily used to bleed the air out. For that, follow the steps in the video. Also you can find more information on this issue in this article.

http://www.ericthecarguy.com/faq/solving-automotive-hvac-problems

Good luck and keep us posted.

[Author]

Replies