2000 LS 3.9 No Heat

[metalriff]

Hi I have a 2000 LS with the 3.9. I had overheating issues and replaced the thermostat, water pump, t housing and degas tank. No issues at all over heating now, most of which was the degas tank was cracked. Air works great but I have no heat. I checked the the #1 fuse in the underhood box and that is fine. I do notice that the passenger side doesnt blow the same temp as the drivers side. Would this lead me to believe its the DCCV control or heater valve is shot? Thanks

 

[joegr]

First things first, Was the degas bottle Motorcraft?
Did you correctly fill and bleed to the letter of this procedure?
http://www.lincolnvscadillac.com/tech/drain-lincoln-ls-cooling-system/

 

[metalriff]

First things first, Was the degas bottle Motorcraft?
Did you correctly fill and bleed to the letter of this procedure?
http://www.lincolnvscadillac.com/tech/drain-lincoln-ls-cooling-system/

Yes, its bled correctly I believe. I didn't change all those at once so I've bled it a number of times. Thanks

 

[joegr]

It's not impossible that it's the DCCV, just unlikely. The DCCV could be clogged.

So, you're sure it's not a Dorman bottle. When you bled it, did you get a steady stream out of the heater bleed?

 

[metalriff]

I just took it on a 800 mile trip, no heat and overheated sitting in Chicago traffic. Still maybe has air in it? 1 heater hose warm the other cold. 3 hours trying to bleed this thing. luke warm then cold following the bleed instructions , just going to scrap this piece of **** and take a loss. More problems ten fold than any vehicle I've ever owned.

 

[RigsLS]

... just going to scrap this piece of **** and take a loss ...

https://www.youtube.com/watch?v=rY0WxgSXdEE

 

[metalriff]

Anyone ever try just bypassing the aux coolant pump? It appears that is the problem.

 

[joegr]

Anyone ever try just bypassing the aux coolant pump? It appears that is the problem.

Your aux pump isn't causing your overheating, unless it is leaking. If it isn't running, it will cause a no-heat condition at idle, but if you don't have heat at highway speeds, you may have some other problem.

 

[metalriff]

Chasing this all over. After closer examination I have just one hose going into the heater core very hot. The left top and bottom are just barely warm after my drive into work, 20 mins. Ice cold in cab zero heat. Thanks

 

[joegr]

This is not new information. We established a long time back that you don't have coolant flow through the cores. If you did, you would have heat.

No heat = no flow = coolant not being pumped or coolant flow blocked.

Not being pumped = aux pump and water pump failed. Since the engine is being cooled at least most of the time, we can discount this.

Coolant flow blocked = leaking plastic letting air into the system (air blocks flow), blockage in upper radiator hose tee (there's a filter screen in there), blockage in the aux pump, blockage in the DCCV, DCCV stuck closed, blockage in both heater hoses, blockage in the heater return hose, blockage in both heater cores (hasn't happened yet).

It really is as simple as this.

 

[metalriff]

I will check the screen and DCCV today. BTW hose at tee is very hot so hoping it is the dccv inop or clogged. Too bad it is such a bear to get to! New water pump and engine runs dead center on gauge all the time. Thanks

 

[1LoudLS]

New water pump and engine runs dead center on gauge all the time. Thanks

not that this is your problem, but its worth noting the needle is not linear... the car is technically overheating before the needle even moves off of center.

 

[Jay Will]

I have a 2004 3.9 LS that is overheating and has no heat. Ive changed the waterpump thermostat housing and water outlet. no leaks

 

[joegr]

I have a 2004 3.9 LS that is overheating and has no heat. Ive changed the waterpump thermostat housing and water outlet. no leaks

No leaks that are obvious to you, but there are leaks.
You must do all this: GenII LS8 Cooling System Overhaul
Then you must fill and bleed it exactly as instructed here: 2006 Lincoln LS Workshop Manual