Fox T-Bird/Cougar Forums

Technical => Engine Tech => Topic started by: seanef26 on December 30, 2004, 10:42:05 AM

Title: Head Gasket?
Post by: seanef26 on December 30, 2004, 10:42:05 AM
Ok...time for the stupid question of the day.  I have an 86 Cougar 5.0 and I think it might have a bad head gasket.  If the gasket is blown will the car still run?  I can hear what sounds like air escaping from the block somewhere, and the car is definately lacking power, but it still runs and drives ok.  So does a bad gasket mean that the car won't run anymore, or just that it will run badly?  Maybe it's just on it's way out and not quite all the way blown yet?  Thanks!
Title: Re: Head Gasket?
Post by: Sly1990 on December 30, 2004, 11:27:07 AM
Do you burn oil? Coolant?
Do you have strange white stuff accumulating in your oil?
Do you have Misfire?

What are the symptoms? :dunno:

Maybe the air you hearing is only a Exhaust or vacum leak
Title: Re: Head Gasket?
Post by: seanef26 on December 30, 2004, 12:26:47 PM
Yeah it loses about a quart of oil every week and a half or so.  About a month ago I noticed a small amount of milky liquid in my oil, but it was only that one time I checked it and I have not seen any since then.  The engine seems to misfire only in the very low RPM range.  Like if i'm accelerating and it hits about 40 mph, the tranny will shift into the next gear and start stumbling and jumping until i press the pedal and make it shift into a lower gear.  Once it's up to cruising speed, it does fine.  When I first start it and the engine is cold, I can hear this flapping (only word I can think of) noise like air is escaping somewhere near or just below the valve cover.  But once the car is running for a few minutes that noise goes away.  HELP!!!  :)
Title: Re: Head Gasket?
Post by: Chuck W on December 30, 2004, 01:17:24 PM
I had one blow to the outside on an 85 30th Anny we had.....no mixing of fluids, just a very bad exhaust leak and a dead cylinder....
Title: Re: Head Gasket?
Post by: SirChirpAlot on December 30, 2004, 02:00:45 PM
Well just for fun with motor running take oil fill cap off and see if the air starts to come out like a Choo choo.
If so then its blow by = rings

There are a few ways to check a motor for a few things at once,
leak down test of the motor.  Compression test will show a little bit but leak down will do alot better,

Test the cooling systom by presure test or vacuum leak down as well.  2nd one is better.
Title: Re: Head Gasket?
Post by: TurboCoupe50 on December 30, 2004, 06:25:08 PM
My guess is you have a bad one way valve in the smog system. This noise on the passenger side??
Title: Re: Head Gasket?
Post by: jcassity on December 31, 2004, 08:31:01 PM
i agree with our resident expert,, smog pump tossing out some noise would be my guess.  Dont be so quick to place blame on the headgaskets without the diagnostics to proove it. 

blown head gastet symptoms
leaking coolant on the ground
coolant appears in your oil
compression on two cylinders are identical
compression on one single cylinder is way way low compared to the rest.