cooling fan noise

M

Mark8toLS

New LVC Member
Joined
Apr 20, 2011
Messages
6
Reaction score
0
Location
Ocala
2005 LS Sport V8, >90,000mi. Owned car since 2008. Once weather began warming up, I noticed fan noise would get very loud after normal engine temp and AC on. Sounds like very loud howling sound as if fan too fast or insufficient air flow. Removed debris from front of radiator and pressure washed as much as possible w/o removing radiator. Changed top plastic rad hose connector (due to pin hole leak), fluid, and purged air. No grinding/bearing sound. Cools properly and recurrance of loudest sound is less but still occurs. It's like top fan speed isn't regulated properly. Also tried to check fan blades for damage. Dealer did hose change and second fluid change.

Any ideas?
 
very common issue.

can be anything from a stuck thermostat to the system not pressurizing correctly due to cracks in the degas bottle or a bad cap.
 
Thx, the service tech told my friend that brought the car in for repair that losing a fairly small amount of coolant can cause the system to overcompensate by increasing fan speed. Had I done the work myself, I would have changed thermostat as well. He should have pressure tested however. I did have to add more fluid a couple days after repair but seems to be holding steady now. That's why I wasn't strongly considering degas/cap. Are those dealer only parts?
 
Mark8toLS said:
Thx, the service tech told my friend that brought the car in for repair that losing a fairly small amount of coolant can cause the system to overcompensate by increasing fan speed. Had I done the work myself, I would have changed thermostat as well. He should have pressure tested however. I did have to add more fluid a couple days after repair but seems to be holding steady now. That's why I wasn't strongly considering degas/cap. Are those dealer only parts?
Click to expand...

No, but as bad as it is, the Ford part seems to be better than the Dorman one.
I do think that your best bet is to replace the degas bottle and see if that resolves it. Even if it doesn't, I promise that you either needed it or would have needed it soon. I doubt that you need a need cap.

Max can sell you the Ford one at a good price.
 
I suggest you get the thermostat and do a flush as well along with the bottle.

And yes low fluid can cause the fan to work harder as well.
 
Did a flush first myself last month. But will add the degas, etc to list. Although I'm not seeing leaks from the rear air purge port, it looks cheaply designed and thought of replacing this also. Emailed Max this AM for rear toe link and sway bar link prices. Saw his comments from prior posts. He sounds like a huge asset to LVC. Does he usually reply same day or suggest I call 5star?
 
It takes him awhile to reply but if you call you can get him right away.
 
i usually get a response either later that day or the next.
 
ok now mine is getting louder but i have also had overflow from the res on passenger side that holds the fluid for hydraullic fan and its only on really hot day my first thought is fan clutch going out and only today did i notice a small spike in temp above midline where it normally is any ideas guys. goin out now to fill rad up a lil as i havent done it since feb when i bought it, im pretty certain it doen not have a crack in res as it over flows from top and upon stoppin and popping hood it is bubbling hot in res.......thanking god winter is coming i love my ls but need a pickup lol....01 ls v8
 
PRICE717 said:
ok now mine is getting louder but i have also had overflow from the res on passenger side that holds the fluid for hydraullic fan and its only on really hot day my first thought is fan clutch going out and only today did i notice a small spike in temp above midline where it normally is any ideas guys. goin out now to fill rad up a lil as i havent done it since feb when i bought it, im pretty certain it doen not have a crack in res as it over flows from top and upon stoppin and popping hood it is bubbling hot in res.......thanking god winter is coming i love my ls but need a pickup lol....01 ls v8
Click to expand...

Your car does not have a fan clutch, so we can safely say that's not your problem.
The hydraulic fan reservoir should only have Mercon V in it. If it is foaming and bubbling out, either someone has added something (like water or coolant) or you have a leak on the low pressure side of the fan hydraulic system. (This would allow air to be sucked into the pump causing the fluid to foam up.)

How does the fluid in the reservoir look? If it's milky, then it's contaminated. If not, time to find the leak.

The noise you hear is the fan pump trying to pump foam when it was designed to pump only liquid. The car is starting to overheat because the fan pump can't drive the fan as fast as it should since it is not pumping just Mercon V hydraulic fluid.

BTW, the hydraulic fan reservoir is not known to crack. It's the degas bottle that is famous for cracking. It's located on the driver's side near the windshield. It has the "radiator" cap on it and is where you top the coolant off. There's no way to see the cracks in it without removing it from the car.
 
ok i was conffuzled sorry for the incorrect term. thx 4 the response coolant looks fine aka green not milky hydro fluid aka mercon v looks red and normal...... its not foaming however it will almost bubble to a boil buy the time i get the car where i need to get it and get it off and pop the hood to look it is just hot in there there is a little debris on the outside of the rad as i stated (sorry for crossposting just a lil frantic to fix) i will be cleaning that off today hiwever it only seems total to be covering less then 25% of surface area of rad in different spots would that be enough to make all my systems go hinky???? i am def not leaking any hydro fluid anywhere as the only time i loose it is when i have this issue and it is def coming out the top of res
 
You have a pin-hole leak on the suction side of the hydraulic pump. It is sucking air in and causing the bubbles. (I assure you that the Mercon V is not overheating and boiling.)

You need to fix the hydraulic system, replace the hydraulic system, or convert to an electric fan.
 
You must log in or register to reply here.

Members online

No members online now.
Total: 200 (members: 0, guests: 200)
Back
Top