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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Brown Antifreeze?

  • Thread starter Thread starter camon
  • Start date Start date Jul 26, 2009
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 26, 2009
#1
  • Jul 26, 2009
  • #1
Hello everyone!

Having an issue with me stang.

Car Description:
2001 Silver Mustang GT 5spd (70,000miles)
NOS Direct Port Nitrous System
Long Tube headers
MAC Cat-Back System w/ProChamber
ACCUFAB Plenum and 70mm Throttle Body
MAC CAI
I own the car about 4 years, bought it with 16,000 miles on it (all mods done by previous owner with the exception of Accufab plenum and throttle body). I never ran the car on the bottle (nice conversation piece)!

Problem:
The radiator is 1 year old (replaced because of puncture in old one).
Anyway......I drained old antifreeze yesterday and replaced it with new 50/50 Prestone and I noticed that the old drained Antifreeze was brown in color and had what I think appeared to be oil mixed in. It still smelled like antifreeze but the condition of the coolant concerns me greatly. I noticed this odd colored antifreeze about 7 months ago and assumed maybe the radiator shop used a brownish colored antifreeze (so I didn't think much of it at the time). Now however, with it laying in the drain pan it appears to be oil mix in it!
I fill the rad. up with new antifreeze and went to AutoZone to get synthic mobile one oil to change and check the condition of the oil (expecting to see antifreeze contamination). When I got back to my garage and did the oil change, I was surprised that the oil didn't appear to have antifreeze contamination (not in oil, under filler cap or on dip stick). I thought maybe it wasn't oil after all!

Well now since the car had time to cool again I thought I would check the coolant level. I removed the coolant cap and looked in filler tank and the antifreeze was again brown in color.

I'm assuming this means I have a blown head gasket, but don't understand why it is getting oil in antifreeze and not antifreeze in oil ?

B.T.W: The car isn't over heating, isn't gaining or losing coolant and doesn't appear to be losing any "significant" oil between 3 month oil changes (not enough to add any between changes anyway)! The car also run very strong and has no weird noises (It drives and pulls as strong as the day I go it)!

My questions.....
1. If it is a head gasket why isn't it mixing antifreeze into the oil as well?
2. Is this a terminal condition, can it be driven til I have the time to either fix myself or get the funds together for a shop visit?
3. About how much is this repair going to cost me if taken to a shop?
4. Is it an easy DIY repair?
*I have some general repair knowledge, tools and a garage and have done engine work on my v6 Fieros in the past (engine swap, removed fiero heads to get exhaust bolts drilled out ect...). My mustang engine knowledge is limited (especially the modular 4.6 liter)... I have done brakes, fuel tank filler grommet, and some other minor repairs on the mustang but never ripped the heads off or intake for that matter. Not to mention this is my daily driver!
 

eliteJAE

Member
May 29, 2007
0
1
16
Stanford University
Jul 26, 2009
#2
  • Jul 26, 2009
  • #2
Yea sounds like a head gasket to me too. Do a compression test on the cylinders or through the radiator and you'll know for sure. The only concern I would have driving around with a possible gasket failure is the possibility of hydrolock and overheating, although you don't have any overheating, hydrolock is still a very real threat and then you'll have to replace more than a gasket.

When I blew a head gasket I had it changed by a backyard mechanic because I was 17 and didn't know any better lol it doesn't look like that hard of a job, as long as you keep the cams in their original position so you don't have timing issues when you put it back together. I paid 700 when I had mine repaired, but I had to have the heads planed and do a bunch of other work like change timing guides, seals galore, etc.

good luck man.
 
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 26, 2009
#3
  • Jul 26, 2009
  • #3
Yeah I thought it was the Head gasket (just never seen it contaminate antifreeze and not oil).

Well Thanks for the quick reply and I quess I will start googling head gasket replacement to see if I can do it myself. Looks like this coming weekend just got alittle busy for me!

Any advise or links to write-ups on this job from the forum techs would be appreciated!

Thanks again!
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
Jul 26, 2009
#4
  • Jul 26, 2009
  • #4
I wouldn't jump in and call a head gasket just yet. Could be the anti-freeze was contaminated with something and just didn't get it all out with the flush. It could be it was treated with some sort of sealer. They have the consistency of oil and my cause the issue you describe.
 

FoxRod87

Active Member
Feb 1, 2006
243
1
27
Carolina
Jul 26, 2009
#5
  • Jul 26, 2009
  • #5
I would flush the cooling system really good. And run the car and see if you see a problem. If you are not seeing a loss in coolant then it is not going to hydrolock. It would need to loose a noticeable amount of coolant to hydrolock.
 

eliteJAE

Member
May 29, 2007
0
1
16
Stanford University
Jul 26, 2009
#6
  • Jul 26, 2009
  • #6
like I said in the other post, try and get a compression test before you tear it apart. That'll let you know if that's where the problem is.
 
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 27, 2009
#7
  • Jul 27, 2009
  • #7
Thanks again guys!

I was planning on testing the cylinders before tear down this weekend. What are good cylinder numbers (variance)?

As for sealant....
I'm am doubting this is the cause (you never know though). I have owned the car for alittle over 4 years and bought it with only 16,0000 miles on it (It was very well maintained and in flawless condition). The car was and for the most part still is in show condition! I know the rad. shop didn't use sealer in the car because all they did was drop in the new rad!

We will see this weekend I quess!

Thanks again guys!

Keep thoughts coming, if anything is floating around out here!
 
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 27, 2009
#8
  • Jul 27, 2009
  • #8
sorry possible false alarm!

Well I couldn't wait for the weekend (wasn't losing another nights sleep)!

I went down to the garage after work today and started pulling plugs one by one and testing the holes.
All holes tested were in the 155-160 area (not sure what the numbers are suppose to be, but all cylinders tested were close). However I didn't pull #3 or #4 (i'll do those 2 over the weekend) because my CAI will need to be pulled to get to these and I really didn't have the time to mess with the CAI (more time this weekend)!

Also I may have over reacted to the drained coolant! My brother informed me that he did an oil change a few weeks back and while he transfered the oil from the pan he didn't rinse it, I always rinse the pan for this very reason (see if I let him use my garage and tools without me being present).
***I have an enclosed drain pan***

This would explain the massive amount of oil I seen floating on the coolant. The orginal coolant in the rad. might've just been really dirty with debis floating in it and I mistook that debis for oil. I just checked the fresh coolant in the car and though it is dirty I don't see any puddles of oil in it just really dirty coolant and some small debris floating around!

So this weekend after testing the final 2 holes I'm gonna try to flush the cooling system which should be "just alittle easier" then tackling a head gasket!

Everyone I talked to plus my own experience, I 've never seen contamination in coolant and not in the oil! So knock on wood with my fingers crossed.....I may just need a flush!

Thanks to all that have read and responded to this thread, and I apologize for (HOPEFULLY) a false alarm!

Will will update this thread this weekend with my findings!!!!!!!!!

Thanks again!
 

eliteJAE

Member
May 29, 2007
0
1
16
Stanford University
Jul 27, 2009
#9
  • Jul 27, 2009
  • #9
LOL that's funny stuff man, there's probably nothing wrong with compression numbers like those haha
 
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 28, 2009
#10
  • Jul 28, 2009
  • #10
I feel alittle better about the situation right now!
I will feel 100% once I get those last 2 holes checked on Friday night!

Man this would've sucked. Biggest problem this car had in the 4-5 years that I own it was an IAC (irratic idle sometimes) and the gas filler neck grommet!

Go from those 2 minor things to blown head gasket (would be just my luck though)!

I'll keep thread posted!
 

TheSalad

New Member
Aug 3, 2003
372
0
0
Utah
Jul 28, 2009
#11
  • Jul 28, 2009
  • #11
I do not know much, but that does not sound like a blown head gasket to me. I bet the other two cylinders test fine and that you just have some dirty coolant.

After the test, flush it good and see what happens.

If it comes down to it, the head gasket change is pretty intensive, but it is doable. Hell, I did it.


Good luck. I hope it is nothing.
 
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 28, 2009
#12
  • Jul 28, 2009
  • #12
Pics of car

See if I remember how to post picks (if so I will show off a couple shots of my Mustang)!

Under Hood Shot


Dusk Shot
 

1992 2.3LX

New Member
Dec 5, 2002
885
0
0
Ky
Jul 29, 2009
#13
  • Jul 29, 2009
  • #13
If it was just brown like this it just needs to be flushed really good.
View attachment 250166
Took me 9 flushes to get it clean, so it can take awhile.
 
C

camon

New Member
Sep 19, 2005
29
0
0
Jul 29, 2009
#14
  • Jul 29, 2009
  • #14
WOW

No!

Mine wasn't even close to looking like that!

That looks like paint

My looked like murky / dirty water and what I seen on the top was black colored debis (after drained of course in a oil contaminated drain pan, I thought the black debris was oil)!

The coolant has gone back to looking like murky / dirty water since the coolant change a few days ago, so a flush is in order asap!

He11 the condition of my coolant had me REALLY worried! I would've really thought something was wrong with my car had my coolant looked like that !
 
C

camon

New Member
Sep 19, 2005
29
0
0
Aug 1, 2009
#15
  • Aug 1, 2009
  • #15
Well i'm back!

I completed the compression test, I made one small error though! I forgot to test the cylinders @ WOT!

What will the WOT do for the numbers (raise or lower)?

Anyway here are my findings ***DRY TEST***:
(cranking about 4 cylces for each cylinder)

#1- 160psi
#2- 155psi
#3- 160psi
#4- 160psi
#5- 155psi
#6- 160psi
#7- 145psi
#8- 150psi

Hole 7 is the only one that i'm slightly concerned about, as it is 15psi off from my highest reading holes of 160psi.

Are these decent numbers?

I also did a quick flush of the coolant system with a case of destilled (sp?) water. I then Refilled the system with coolant and took the car for a 30 mile drive. The cooland color looks pretty good (dumped in the water, idled car for 5 mins, shut off, and drained....repeated this 3 times, lastly filled car with new coolant and buttoned it up )!

Well let me know if I'm gonna need to retest this thing @WOT to get a more accurate reading, and if cylinder #7 is reason for concern????
 
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