Taurus Car Club of America : Ford Taurus Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
52 Posts
Discussion Starter · #1 ·
I just recently had my heater core changed on my 94 ford taurus 3.0. I had to take it back to the place that worked on it becuse one of the heater core hoses started leaking. When I came to pick it up the guy said that they fixed the leak (hose was too short and clamp was loose) but he said that I had excessive pressure in my coolant system when he pressure checked it. The mechanic then tried to tell me it is probably the head gasket.

The car doesn't exibit any signs of having a blown head gasket...IE coolant in the oil...loss of power, white smoke...or overheating. It runs fgreat... Is there anything else that could cause this besides exhaust gases entering the coolant? Also what is excessive pressure? what is the norm?

Here is the scoop...

Car is a 94 taurus with the vulcan 3.0

when car WAS leaking coolant at the heater core it was a small leak and did not overheat the car...temps fluctuated netween the N and the A in normal due to air entering the system because of the leak.

When the leak was fixed and fluid refilled. temps are between the O-M in "NORMAL" on the gauge.

it is 97 degrees/ 90% humidity-could that effect the pressure tester.

-any help is greatly appreciated
 

·
Premium Member
Joined
·
14,126 Posts
If the pressure is greater than what the cap is rated it will puke out coolant at the cap. And the radiator will be low when cold before you start it. Fill the radiator completely, when cold and check it every day before you start it.

The cap may be bad too but they tend to go bad the other way, not holding pressure and may run hot.
 

·
Registered
Joined
·
43 Posts
When your engine is warmed up, try to squeeze the upper radiator hose (with a glove on) and see how firm it is. If it is rock hard, I would suspect excessive pressure. If it remains very hard after the engine has had sufficient time to cool, (not overnight) then I would think the mechanic was telling the truth.
Do this after you fill the system up cold. The upper hose should still have a little 'give' even when the engine is at operating temp.
It takes a while for the coolant to get milky. Gasket could have failed very recently.
 

·
Registered
Joined
·
56 Posts
A minor HG leak won't show the signs U listed; a major leak will. A minor leak will create some excess pressure until it gets worse and then will show the classic symptoms U mention. IMO, U should throw up to 2 tubes of Aluma-seal in the cooling sys. and hope for some luck. Yeah, I know the score w/ this stuff, but my Z has survived 2 decades w/ this, so I'm not going to say it never works like some people.
 

·
Premium Member
Joined
·
14,126 Posts
Aluma seal. Good way to block up a good heater coil IMHO.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #6 ·
Well i will check the hose in a few minutes..What is strange is that right after the mechanic put the heater core in and I picked up the car. he said it pressure checked good and there were no leaks..then when the heater core hose started leaking and I brought it back 4 days later. he said the system pressure checked high..this in the course of 4 days the Head gasket goes bad?..Maybe so but it just seems odd to me. isn't there some test I can get to test for exhaust gas in the coolant? what else besides a HG could cause excessive pressure..anything? I think he said I was at 20 lbs but my cap was rated for 16. I don't know
 

·
Super Moderator
Joined
·
8,672 Posts
If the cap is a 16 psi and the actual system pressure was measured to be 20 psi, either the cap is bad (should vent at 16 psi, meaning the max pressure that can exist in the system is 16 psi) or the mechanics pressure gauge is wrong, or he is trying to cover up is poor workmanship of using the wrong hose and not correctly tightening the hose clamp.
 

·
Premium Member
Joined
·
14,126 Posts
How did he check pressure with your cap on? They usually check the system pressure by attaching the tester to the radiator cap opening. Then use an adapter to check the cap.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #9 ·
"When your engine is warmed up, try to squeeze the upper radiator hose (with a glove on) and see how firm it is. If it is rock hard, I would suspect excessive pressure. If it remains very hard after the engine has had sufficient time to cool, (not overnight) then I would think the mechanic was telling the truth.
Do this after you fill the system up cold. The upper hose should still have a little 'give' even when the engine is at operating temp.
It takes a while for the coolant to get milky. Gasket could have failed very recently. "




OK so after about an hour of letting the car cool down I was able to squeeze the upper hose and collapse it completely with no problem. It wasen't super hard or anything. System is full
 

·
Premium Member
Joined
·
14,126 Posts
Take you car to AutoZone and have them test the cooling system and pressure cap. Or rent their tool and do it your self.

After an hour you car has coled down enough to negate the squeeze test.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #11 ·
How did he check pressure with your cap on? They usually check the system pressure by attaching the tester to the radiator cap opening. Then use an adapter to check the cap.

I am not sure how he tested it, he had the car buttoned up when I got there. I would of liked to see the results.
 

·
Registered
Joined
·
43 Posts
OK so after about an hour of letting the car cool down I was able to squeeze the upper hose and collapse it completely with no problem. It wasn't super hard or anything. System is full
Sorry, I was somewhat vague about the cool down time interval.
I should have said: If the hose gets super hard when your engine is fully warmed up (or even sooner), then you proceed to letting the engine cool down and seeing how quickly the pressure dies down. You need to check it within 15 minutes of shutting the engine off, and at 15 minute intervals there after.
Test the pressure cap 1st before making the assumption of blown HG.
If the cap checks out OK, and you are getting a rock hard hose, then I would suggest taking it to a different shop and having them test the system pressure (second opinion).
 

·
Premium Member
Joined
·
14,126 Posts
Well if there is any problem with overpressure then the first thing that needs checked is the cap. Caps usually fail in the other direction and get to the point they cannot maintain pressure.

It makes no difference as to what is causing the pressure.
 

·
Registered
Joined
·
52 Posts
Discussion Starter · #14 ·
could a clogged cooling passage or partically clogged passage create pressure? I heard the water pump impellers on these cars tend to disintergrate over time. I am fairly certian that the WP is the original. is it possible that sludge build-up /metal from the WP is clogging passages causing excessive pressure? I don't know just throwing it out there.
 

·
Registered
Joined
·
100 Posts
Not trying to hi-jack the post but, what if the hose is still rock hard after 20 minutes of driving and the Resivor tank is BULGING out?
 

·
Premium Member
Joined
·
14,126 Posts
Sounds like your system is holding good pressure. Hoses and tank may be in need of replacement though.

The hoses will have short cracks inside way before any thing is noticed from the outside. This causes them to loose their "binding" strength.
 

·
Registered
Joined
·
100 Posts
Everything is new-radiator, waterpump, all hoses, resivor tank and cap and t-stat. All replaced about 2-3 months ago. But if that's good then I can live with that.
 

·
Registered
Joined
·
10 Posts
Not trying to hi-jack the post but, what if the hose is still rock hard after 20 minutes of driving and the Resivor tank is BULGING out?
How in the heck does a red tank "BULGE" out? My is hard plastic and would never do this so im confused...lol.
 

·
Premium Member
Joined
·
14,126 Posts
Assuming the coolant pressure cap is working OK it is either completely normal or the parts bulging need replaced.
 
1 - 19 of 19 Posts
Top