intermittent overheating... - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars
Ford Forum Ford Forum

» Auto Insurance
» Featured Product
ยป Wheel & Tire Center

Go Back   Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > Ford Cars and PAG Vehicles > Ford Taurus | Mercury Sable | Ford Taurus SHO | 1986-2007
Register Home Forum Active Topics Photo Gallery Auto Loans Garage Mark Forums Read Auto Escrow

Ford Taurus | Mercury Sable | Ford Taurus SHO | 1986-2007 Forum for discussion of the Ford Taurus, Mercury Sable and Ford Taurus SHO. Covers vehicle years: 1986-2007

FordForums.com is the premier Ford Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 02-27-2012, 03:47   #1 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 28
intermittent overheating...

It figures, I brag about how great my car runs and a new problem shows up.
Car had an intermittent overheating problem that became serious right after I bought it--about three weeks ago. I changed the water pump and thermostat and flushed it out with clear water and the problem was solved or so I thought.
I recently drove the car about 130 miles in one day and it ran beautifully, but yesterday it started overheating again and showed the low coolant light after just a few blocks.
I have searched the forum and found several more things to check out, but nothing exactly like this.
All six cylinders pass a compression check, plugs were normal in color and appearance. No coolant in the oil or vice versa. No steam out of the tail pipe and no coolant leaks. There is almost no way this can be a head gasket.
The system seems to build pressure and blow the coolant out the top of the coolant recovery tank. I replaced the cap and it still happens.
Wife drove the car 2.5 miles to work this morning and it did not overheat, but it did overheat three times ( we NEVER allow the gauge to go above about 75% as this is an aluminum engine and they cannot take the heat). But no problems showed up the day before.
Can't be the weather as I am in Kansas and it is quite cool here this time of year.
So, I have replaced the water pump and thermostat and radiator cap and coolant, flushed the radiator with plain water, and will back flush the heater core this afternoon. The accessory drive belt is new as are the plugs and wires. What else can it be?
I have heard of exhaust pressurizing the cooling system due to a bad head gasket, but wouldn't that cylinder fail the compression check?
tonyb1968 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 02-27-2012, 05:13   #2 (permalink)
Moderators
 
Join Date: Apr 2007
Location: Scotland
Posts: 10,043
Re: intermittent overheating...

A block test will confirm one way or another whether head gasket is leaking .
R.S.LOGAN is offline   Reply With Quote
Old 02-27-2012, 08:13   #3 (permalink)
Moderator
 
Join Date: Nov 2008
Posts: 1,067
Re: intermittent overheating...

You are describing the typical problems of a blown head gasket but a cracked head
will do the same thing.
chipset is offline   Reply With Quote
Old 02-27-2012, 20:45   #4 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 28
Re: intermittent overheating...

It just seems to me that if it were a block or head, the problem would be consistent. It runs fine one, two, even three days in a row then may heat up once and burp up some coolant then the problem disappears for days again.
I hope it is not a head gasket or head because I am broke and have to turn wrenches myself with the help of my 18 year-old son. Head work has always been tough for me and these DOHC's seem like they will be a nightmare.
tonyb1968 is offline   Reply With Quote
Old 02-28-2012, 04:48   #5 (permalink)
Moderators
 
Join Date: Apr 2007
Location: Scotland
Posts: 10,043
Re: intermittent overheating...

" burp up some coolant " can be caused by head / gasket knackered as it can cause an airlock or pressurise cooling system .
R.S.LOGAN is offline   Reply With Quote
Old 03-06-2012, 12:22   #6 (permalink)
Registered User
 
Join Date: Mar 2001
Location: gawga
Posts: 122
Re: intermittent overheating...

I, too, would be looking at a cracked head. You can test for combustion gases in the 'degas' bottle with the appropriate machine {I don't have one...} and if there, you have leakage from the combustion chamber to the water jacket area somewhere. Typically, when you get high pressure in the cooling system it is a head gasket or crack.
Other things to consider rule of thumb are that if it gets hot in stop and go traffic, it is likely the pump {or electric fan}, and if it gets hot going down the freeway, its a stopped up radiator.
The computer 'knows' how fast you are going, and is to turn off the fans when velocity is greater than some number {mid 20's or 30's}, but to engage the fans when the A/C is energized. I don't remember all the strategies they used.
A final thing to consider is a sticky thermostat. You might be ahead to get a non-contact thermometer to read the temperature of the hoses, stat housing, radiator tanks, top and bottom, either end, and the return flow to the block. You should get a picture of what is going on if you have access to all that....
tom
tomw is offline   Reply With Quote
Old 03-20-2012, 19:45   #7 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 28
Re: intermittent overheating...

Update:
Refilled radiator several days ago and "low coolant" light has not came back on, coolant "burping" has ceased, has not even begun to overheat again.
I began to notice that it only happened when the heater was on so I turned it off and flushed a lot of plain water thru the system. It was VERY dirty. Coolant is much cleaner now and problem has ended apparently. I still intend to flush the heater core properly and replace the thermostat again just to be on the safe side.
Several guys have recommended drilling a couple of holes in the thermostat to allow some improved circulation. May consider this unless it would be unsafe. Two 1/8 inch holes would allow some circulation to continue while the thermostat is closed, but should still allow for the thermostat to operate properly.
There was no exhaust gas in the coolant recovery tank and everything else checked out. Seems to have been a restricted heater core. Problem has been gone almost since my last post.
tonyb1968 is offline   Reply With Quote
Old 03-21-2012, 08:06   #8 (permalink)
2002 F150 XLT
 
Bert's Avatar
 
Join Date: Nov 2008
Location: Oregon
Posts: 9,702
Re: intermittent overheating...

That's good the hear. Thanks for keeping us posted.
__________________
Bert
Bert is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply

  Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > Ford Cars and PAG Vehicles > Ford Taurus | Mercury Sable | Ford Taurus SHO | 1986-2007



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Powered by vBadvanced CMPS v3.2.2

All times are GMT -7. The time now is 16:20.



Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.6.0
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.