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Topic: Timing belt? (Read 2066 times) previous topic - next topic

Timing belt?

'86 Cougar 5.0

Well, my friend's dad said that there's a small possibility that it's not my head gasket, but my timing belt might be going bad.  He said something about a water pump gasket and that if it's bad, that might be what is allowing coolant into my oil.  With all the symptoms i'm having (water out of tailpipe, coolant in oil, bubbles in radiator) I was pretty sure that it was a head gasket.  Is it possible that this could end up being a much cheaper timing belt and gasket repair?  Any of you guys ever heard of this?    :dunno:

Re: Timing belt?

Reply #1 –
Water pump gasket will only leak water/coolant to the outside of the engine.  The intake gasket, however will allow coolant and oil to mix.  If you're tearing it down, stop at the intake gasket and check for signs of leakage.  That may be the only problem.  PS - Your car has a timing chain, not a timing belt.

Re: Timing belt?

Reply #2 –
I'll bet you it's the head gaskets with the symptoms you describe.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Re: Timing belt?

Reply #3 –
The bubbles do make me think it's a HG, but the intake can, indeed allow cooland and oil ti mix.

Re: Timing belt?

Reply #4 –
The timing cover gasket can mix oil & water, but it's unlikely. Because you've got water coming out the tail pipe and bubbles in the coolant I'd have to agree with these guys that it's your head gasket.

BTW, 302's (and 3.8's) don't have timing belts, they have chains. When a chain goes bad it usually results in a lack of power and, depending on how bad, a lot of noise. If it breaks it usually destroys the engine. The only engine ever offered in a T-Bird/Cougar with a timing belt is the 2.3 turbo, and when they break they don't hurt the engine.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Re: Timing belt?

Reply #5 –
I didn't think the 5.0s were interference engines.... :dunno:

Re: Timing belt?

Reply #6 –
Yep, they are. Just think - if having too agressive a cam can cause piston-valve contact, just imagine what would happen if the chain broke. Seems to me somebody on this  forum found out the hard way last year...
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Re: Timing belt?

Reply #7 –
Both my Cougar and T-bird had loose chains and they both skipped so far that the motor lost proper compression and wouldn't fire, but I never had one break all the way and cause interference.  Obviously I fixed the t-bird.