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Totally Stupid Question... Exhaust Manifold CRACKED!...black fluid?

4K views 30 replies 5 participants last post by  AC75TB07 
#1 ·
This is probably going to sound really stupid, but would a cracked exhaust manifold maybe drip any form of black fluid or something? Like maybe the heat or exhaust fumes escaping under the engine is creating some condensation that then runs down and drips on the ground when you stop?...My manifold is BUSTED & LOUD and I sometimes see a bit of what looks like black watery fluid on the ground when I park, but I have no reason to suspect any kind of other leak. Just a thought...
 
#3 ·
1. The exhaust manifold definitely needs to be changed because over time it will become louder and louder.
2. The fuel consumption will be increased.
3. You will receive CEL on the dashboard. (Now it may not be)
4. You will need an exhaust manifold, gasket, mounting bolts (11 pieces) and a receiving pipe ring

P.S You can determine the composition of the liquid, what is it? Engine oil, antifreeze, brake fluid, etc....
 
#4 ·
The OP said it drips.... so it must be a significant amount of whatever liquid it is in sufficiant quantities to actually hit the ground.

I would bet it's not brake fluid... there's only a very small reservoir of it and missing not very much would pop at least a low brake fluid warning light..... which might only be the BRAKE WARNING light.... STILL... there'd be a light somewhere!

If the cooling system or oil supply fluids get low.... there'd be other symptoms like no oil on the dipstick or an empty coolant reservoir...... but either loss would be disastrous in short order. Either of those would be a short ride until tow truck time....

If I totally discount the dead squid (whose stupid idea was that anyway!?!) ... I'm thinking the only "fluid" of which it's normal to fall to the ground, is from AC condensate.

But since I may need a GET OUT OF JAIL FREE card here.... I may have to keep an open mind about the possibility of a squid.....
 
#14 ·
If this is a 4.2L six-popper, broken exhaust manifolds are EPIDEMIC. You'll need a heap of individual pieces, OR you buy the "exhaust manifold KIT" that comes with everything except the metric bolts that hold the manifold to the head. Those you will also need, but they're sold separately.

The kit includes a new heat shield. The new heat shield is a poorly-stamped, shameful copy of the "real" GM part, but it works OK. And it's not like "genuine GM" parts have a great reputation any more.

Recommend you install a new O2 sensor while the access is good. You'll never get the old one out and still have usable threads on it anyway. Also recommend you use BRASS nuts on the exhaust studs that connect to the rest of the exhaust pipes. At least use anti-seize on the studs.

For Fook Sakes, use a swivel socket on the exhaust manifold-to-head bolts! They're held in the head with threadlocking compound, they're hard to remove, and they're shiity, soft bolts that will break with the slightest provocation. Any side-force on them is suicidal. The swivel-socket prevents side-force.

I don't know about the Genuine GM exhaust manifolds, but both Dorman "kits" I bought, the iron manifolds were warped right out of the box. Ideally, you'd take it to a machine shop and have it planed before you install the thing. There's no machine shops where I live, so they got bolted-on as-is. Not the best plan.
 
#15 ·
They're held in the head with threadlocking compound, they're hard to remove, and they're shiity, soft bolts that will break with the slightest provocation
Curiously I have the opposite issue. Since buying my 2002 TB used twice I have had to get in there and retighten the exhaust manifold bolts! Damn things keep coming loose! First time in I found all but the rearmost bolt I could turn by hand. I haven't ever removed them, just retightened.
 
#18 ·
But where is the BLACK coming from? PS fluid is typically amber-oil-colored. Either the fluid is burned, the hoses have degraded and rubber particles are circulating in the fluid, or the path the fluid is taking from the leak to the driveway is covered in dirt.

"I" would want to flush the fluid and install all fresh at whatever point the leak gets fixed; and install a power-steering filter if at all possible. $20 put to good use.
 
#19 ·
New steering rack, all new lines, so going to let the garage sort it. It's leaking on the driver side, the same area where the old rusted lines were when I had the repairs done in November. Not expecting it to be much of an issue.
 
#20 ·
Just realized the manifold kit doesn't come with the bunch of mounting bolts... Is there anything special about these bolts that makes them unique that I can't just pic 'em up loose or let the garage use their stock of bolts etc.?...What size and length are they?
 
#21 ·
Exhaust Manifold bolts GM P/N 11609481 (11pcs) (the size m8x1.25x33, 23. 9)

Technology

You should not use old bolts.
They underwent heat treatment for a long time and there is a high probability that if you install them again then the next time they are unscrewed, they will burst. I also don’t recommend using size-appropriate bolts, for the original bolts the tensile strength is 9.8 (you can see these numbers on the head of the bolt) I think the bolts that are sold in a regular store are much weaker. You risk that they burst in the future.
 
#23 ·
The bolts I bought at the home-improvement store, and the Dorman bolts are STRONGER than the crappy GM bolts. GM = 9.8; aftermarket bolts were 10.9. The hardware store bolts were 35mm long, a 5/16 washer gave the same thread engagement as the original 33mm long bolts.
 
#22 ·
The FIRST time I changed manifolds, I bought new metric bolts at the local home-improvement store.

Post 115.

Downside is that all the photos I posted seem to be gone.
 
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