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Odd Coolant Level Problem

  • Thread starter Thread starter ReefBlueHatch
  • Start date Start date Feb 27, 2010

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Feb 27, 2010
#1
  • Feb 27, 2010
  • #1
I'm having constant problems with changing coolant levels.

In November I put in a new radiator, flushed the system, and put in new 50/50. Everything was fine, but I kept noticing coolant dripping on the ground from the overflow spout on the reservoir. There was an excessive amount in the jug, but the radiator level was fine. So I lowerd the coolant level to the cold line and everything seemed alright.

Three weeks ago I drove 35 miles and I let the car sit for three days. Hopped in it and the low coolant light was on. I didn't add anything; the jug was empty, but the radiator level was fine, so I drove home 35 miles. I let it sit a day and the level rose between the cold and hot lines.

Two weeks ago the jug was about empty, so I added 50/50 to the cold line when the motor was stone cold for days. I checked it yesturday and the level was an inch above the cold line. Then I discovered a coolant puddle below the bellhousing area. I started the car up, moved it back 10 feet, and shut it off - ran no longer than 30 seconds. I went out and checked it out this evening and the level is almost to the hot line with the radiator level fine.

I'm sorry for the long post, but I wanted to include the details because I'm baffled by this. Thanks for any help!
 

Celeb

20+ Year Stangneter
Sep 8, 2002
736
13
59
Here and there
Feb 27, 2010
#2
  • Feb 27, 2010
  • #2
Based on where you said you saw a puddle, maybe a leak on the lower intake to block on the firewall side. Possibly an end gasket leak or rear coolant port?
 

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Feb 27, 2010
#3
  • Feb 27, 2010
  • #3
I notice two drops on the ground for the first time last week, but I had a puddle yesturday.

I was thinking lower intake too, or a freeze plug, and praying it isn't a head gasket. I do know it's nothing to do with the heater core/hoses. Where do you mean end gasket or rear coolant port?

Thanks, strike!
 
N

nascarnut921

New Member
Mar 5, 2009
3
0
0
Feb 28, 2010
#4
  • Feb 28, 2010
  • #4
check the rear egr coolant hose. it's connected to the lower intake near the firewall.
 

capri debris

Member
May 5, 2007
289
6
18
PA
Feb 28, 2010
#5
  • Feb 28, 2010
  • #5
Sounds like it's time for a new radiator cap and the leak could be from the egr hose behind the TB, a heater hose or the metal piping the hoses connect to.
 

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Feb 28, 2010
#6
  • Feb 28, 2010
  • #6
The EGR coolant was bypassed by the last owner, but it's so hard to see what was used. I'll probably take the upper plenum off to take better look.
 
N

nascarnut921

New Member
Mar 5, 2009
3
0
0
Feb 28, 2010
#7
  • Feb 28, 2010
  • #7
why a new cap?
 

84Ttop

They make new pistons every day, so why worry?
5 Year Member
Jul 2, 2009
5,222
3,255
204
South Jersey
Feb 28, 2010
#8
  • Feb 28, 2010
  • #8
Try to rent a pressure tester from your local auto parts store, put 16psi in the system and you should be able to find the leak and start from there.
 

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Feb 28, 2010
#9
  • Feb 28, 2010
  • #9
Thanks for help, guys. I'm going to try one of those pressure testers this week.

So what do you guys think about the coolant levels increasing? Because this was going on before I had the leak. Would this have something to do with a blown head gasket putting pressure in the system? Or an old radiator cap not retaining pressure? The outer rubber does have a lot of cracks.
 

capri debris

Member
May 5, 2007
289
6
18
PA
Feb 28, 2010
#10
  • Feb 28, 2010
  • #10
If the cap is rated at 18 psi, then it should allow the system to build pressure up to that point then the inner rubber seal will lift and allow coolant to expand and run down the little hose to the overflow tank. When the system cools down and the coolant contracts, it will cause a vacuum and syphon the fluid back into the radiator. If the cap spring is getting weak, it won't hold pressure and coolant will overflow into the tank sooner than it should. If you change the cap and rule it out as the problem but the coolant still fills the overflow and it spills out, then the next thing to check is for a blown head gasket that is over pressurizing the system.
 

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Feb 28, 2010
#11
  • Feb 28, 2010
  • #11
Thanks for the explanatin, that now makes sense. When I inspected the cap it rattled, I figured that couldn't be good. I'm gonna pick up a new up tomorrow.

BTW, those are the best looking Capris I've ever seen!
 

ReefBlueHatch

Active Member
Jan 12, 2010
682
96
39
Central KY
Mar 2, 2010
#12
  • Mar 2, 2010
  • #12
I picked up a new cap today, so I'll have to see if that helps. The new cap is a little stiffer, but seems to have more spring travel.
 
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