04 Cooling system upgrade problems

rgorke

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Now that I have my 04 LS V8 back together after changing water pump, plastics (cross pipe, 9N499, Tstat housing). The degas bottle, radiator, dccv, and upper and lower hoses.


No leaks!!!


I have bled the system by the book and now if I have the heater on at 90 degrees, the car temp sits right at 207. If I turn the AC to 75, the car temp climbs to 220-225. I turn the heater back up to 90 and the temp goes back to 207.


I have opened the bleed valve several times and don’t seem to get any more air out of the system.


What am I doing wrong and/or what’s potentially broken?
 
Thermostat.
I KNEW IT!!!!!

I know what you’re gonna say but I had to get a non-Motorcraft thermostat due to time constraints and it has kicked me in the, well underside.

It’s a longer story (sob story) than that but will put in Motorcraft tomorrow. (The one that was in before my leak was only a year old.)

AND, it did turn out to be the water pump!!! The bearings were shot and it turned like a fidget spinner!!!!

Thanks Joe!!!
 
Motorcraft thermostat back in, system bled, and temp staying under 210, mostly 203-205, even with A/C full blast!

Yep, thermostat!!!

Even knowing better, I broke the “only use Motorcraft” rule!!!
 
First, Thank you Joe for you continued help and input. I am thinking of pulling together a thread of all the best coolant related threads and proposing a sticky.

In terms of the bleeding process, I did it "by the book" and last night after a quick trip to the grocery store, I opened the bleeder and got a small spit of air out. I suppose that this could happen for a little bit of time. It isn't even close to overheating but did get to 215 when it had been at 205.
 
Sorry of this seems an unnecessary bump, but I missed this thread before I posted my own cooling system thread...
I'm having the same problem and am in the process of acquiring the CORRECT Motorcraft thermostat & housing.
And Degas bottle, etc... Already have CORRECT passenger radiator hose installed, and will install CORRECT DCCV when I get all the parts together.
Thanks for posting your symptoms & the solution - which I'm learning like most others ALWAYS is Motorcrsft replacement parts N.M.F.W.
 
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Ugh, and I'm back at this....car has been running great. I had to drive to San Diego, 175 miles each way. On the trip down, temp stayed under 210 unless idling in traffic and up to 220 then back down. All this with the AC blowing.

On the way home, I figured everything was good so didn't monitor temp. When I started sitting in traffic, out of boredom, I hooked up my monitor. The outside temp was mid 90s and everything seemed fine until I was stuck in traffic and the temp started to rise to 225 - 227 - 230.

I turned the AC to full heat and the temp dropped to 210. I did this several times to determine if it was the fact of the traffic or if the same thing happened at 70-80 mph.

I don't see any loss of coolant in the degas bottle.

The thermostat was changed in late 2015. I have a new Motorcraft to install because that is what alleviated the problem in earlier posts.

Any other thoughts?
 
Based on what I've read here and my very limited experience with this car, just because there is no "...loss of coolant in the degas bottle..." doesn't necessarily mean there are no leaks.
Air can be getting INTO the cooling system and causing air pockets to develop over time.
Have you tried bleeding system again? If this temporarily brings your temps back down again, that to me would indicate air is slowly getting into the system somewhere.
I hope I'm not misinforming you, but I trust the LS gurus here will correct me if I'm wrong - hopefully swiftly but mercifully.
Good luck!
Doug H
 
Well, it may be a moot point. I can’t get one of the bolts for the tstat housing out. The brass sleeve keeps spinning.
 
Probably have to pry it apart. The sleeve should pull out then.
 
Thanks...I put everything back together as I couldn’t have it apart too long. Bled it twice and things appear to be good.

I did notice that the throttle body return hose (underneath and connecting to the nipple under the intake manifold and below the 9N499 pipe) was not fully on the nipple at the throttle body...if that makes any sense.

It also appears that I was a little low on coolant that I am thinking led to my high temps the other day.

Fan appears to be functioning properly.
 
hello guys well ive been driving my self crazy with a similar issue.. its a 2005 ls 3.9 had a broken dagas bottle so i replaced (dorman) replaced the thermostat and housing (motor rad) replaced the upper hose and dccv .. when i do the bleeding procedure i can never get the stream of coolant from the bleeder they say.. i set the temp to 90 heat is on the car is fine as soon as i lower the temp to 75 within a min i get boiling in the dagas bottle.. i ran some water with a hose threw the radiator and its flowing normal.. i also pulled the water pump and that seamed fine.. the lower radiator hose stays cool to the touch while the top of that same hose is hot.. im really starting to think its the thermostat.. any input would be great been working on this for a while about to loose it
 
hello guys well ive been driving my self crazy with a similar issue.. its a 2005 ls 3.9 had a broken dagas bottle so i replaced (dorman) replaced the thermostat and housing (motor rad) replaced the upper hose and dccv .. when i do the bleeding procedure i can never get the stream of coolant from the bleeder they say.. i set the temp to 90 heat is on the car is fine as soon as i lower the temp to 75 within a min i get boiling in the dagas bottle.. i ran some water with a hose threw the radiator and its flowing normal.. i also pulled the water pump and that seamed fine.. the lower radiator hose stays cool to the touch while the top of that same hose is hot.. im really starting to think its the thermostat.. any input would be great been working on this for a while about to loose it

Yes, I had a similar issue when not using a Motorcraft thermostat. Honestly, using dorman and other non-motorcraft parts may save a few bucks but they just don't work right and/or fail in short term.
 
The Dorman bottle is known to be a problem. It's probably not sealing well enough to pressurize the system so that it will bleed correctly. I don't know about the MotorRad thermostat, housing and crossover, but it seems like only the Motorcraft parts work well. You need to replace the rest of the plastic as well.
GenII LS8 Cooling System Overhaul
 
Ok guys so installed all motorcraft stuff ..tthermostat and all.. I still can not get the stream out if the bleed tube the lower rad hose is warm now which is a plus but as soon at I lower temp to 75 ..she boils ..need some pointers
 
Did you change all of the parts?
Which ones did you not change?
Did you replace the Dorman tank?
Did you look at the front of the passenger side of the radiator tank up high? (Need to remove the radiator bracket on that side to be able to see it.)

It won't bleed because it isn't pressurizing. It isn't pressurizing because something is still leaking.
 
joe do you happen to know to what temp the fan should be turning on low ? when driving cars fine.. at isle she still getting warmer than i would like to see .. thanks again for the help much appreciated
 

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