Replacing exhaust manifold gaskets. Copper adivsed

[breadbox]

Sent: 3/12/2003 1

The right side gasket on my 1976  318 is leaking and I'm going to replace it soon.
Should I do both sides?
Anything I should do ahead of time in preparation of removing those bolts?
WD40, Heat them, give em a wack with a hammer?

[cartinkr]

Sent: 3/12/2003

I don't know if your exhaust manifold is held on with studs or bolts. If studs, soaking the nuts in wd40 each day, or twice a day, will help. Same goes for the nuts holding the exhaust pipe to the manifold flange. On my 413 I had to torch the nuts off the studs, remove the manifolds, then get the studs out with visegrips, wiggling and soaking with wd40, over a two weeks period. If bolts, just hope they don't break off in the heads. If you get it all apart on one side, I would try the other - as it won't get easier next year. I didnt put new studs back in, but used stainless bolts, with antisieze smeared on the threads, and about each two or three years I loosen and retorque the bolts, to make sure they won't seize, and to make sure they are still keeping the manifold tight against the head. Of course I used new nuts on the manifold to exhaust pipe studs, and put an extra nut on each stud, so the threads wouldn't get so corroded. And I used anti-sieze on those nuts too. 

[MSN Member]

Sent: 3/12/2003 

It's not at all difficult. I sprayed liquid wrench on all the bolts but don't think I really needed to.
By all means, replaced both at the same time. When you buy a gasket, you get a pair, so may as well. Just remember to COMPLETELY clean all the old gasket material off both surfaces, engine and cover.
Not cleaning the surfaces well enough is the most common mistake, with over-tightening the bolts the second most common. My instructions were to hand-tighten the bolts then apply no more than 45lbs of torque to the bolts. unless you've done enough to be able to 'guesstimate' that pretty closely, a torque wrench is a necessity.
With most of the new gaskets you don't even need adhesive. They're held in place by the tabs or 'ears' thru the cover edge. Be careful about all the wires... you don't want to tighten the whole thing down then see a wire vanishing beneath the cover.

[Oz]

Sent: 3/13/2003

Before you take the bolts out drain the anti-freeze from the block to below the heads.

[Graham]

Sent: 3/13/2003

Be careful with the torque settings.  Dodge Chassis manual shows:

Exhaust manifold nuts and screws        20 ft lb

Exhaust pipe to manifold flange nuts:

318-3      25 ft lb

413-3 and 440-3    50 ft lb

PS WD40 is a Water Disposal product Liquid Wrench is a penetrating oil which I've found superior.

[westcoast redneck]

Sent: 3/14/2003

My only advice is:  use a solid copper gasket. I have a 440 which seem to have allot of exaust manifold problems. The copper one did the trick.

[breadbox]

Sent: 3/15/2003 

COPPER IT IS!

These rigs seem to have a history of exhaust manifold gaskets issues.

My searches on copper exhaust manifold gaskets have come up very positive. Here is some pro copper exhaust manifold gasket info.

The factory exhaust manifold gaskets are notorious for their failure to seal against the high temperatures and pressures of performance engines. Thermal expansion of the exhaust manifold tends to pull the OEM gaskets off of their designated mating areas to a point wherein they will actually block/restrict exhaust gasses and its steel/composite construction is prone to burn/blow through under any condition…this hurts engine performance and the latter defeats power providing exhaust velocity on turbo applications. OEM cylinder head gaskets are ample for modest increases in engine performance but simply can't cut the mustard when it comes to high boost/compression of high output engines.

They seal better! Copper conducts heat better than OEM and reduces hot spots at mating surface They are reusable! I'm hoping I can order them special through my local Autozone. Copper looks like it will be around $45 a pair.

FYI:  I found it easy to look up any part for all 6 of  this families vehicles by making a profile for each model at www.autozone.com  I only plan to do one side for now.  I have plenty to do without doing a side that isn’t leaking

[Rick Shaw]

Sent: 3/18/2003

I replaced the exhaust manifold gasket on the right side of my 440.   Now the left side leaks.  Gofigure.   I guess what I am trying to say is do them both at the same time while you have the tools out and the gumption.   The right side was easier on mine because of the clearance from the frame.   The left side will be harder because there is not as much clearance from the frame.   The gaskets that I got did not have the slide factor.  This means that the holes on each end of the gasket were not grooved so that you could just slide them in while you have the manifold pipe pried back from the engine.   I notched the holes on each end of the gasket and it worked like a charm....just slid the gasket right into place.   Remember to put the shiny side towards the engine.  Also ...don't be surprised if you remove a bolt and anti-freeze comes out....a few of the bolts on the 440 engine were water jacket bolts.   The sequence of tightening the bolts and the torque are guides that you should stick to.

[UluzYarx]

From: UluzYarx
Sent: 3/8/2004

Hi Liv,
If you really do have bolts holding your manifold to your cylinder head, I recommend you to get studs, washers, and nuts.
~
Re-fitting an exhaust manifold on a V engine is a job for a three handed mechanic at the best of times, bolts will only make it worse.
~
I keep a stud extractor handy on the basis that I'll be bound to need it if I haven't got one.
Bolts shear.
~
Running your engine to warm it up before you tackle the job helps on a cold day.
The bolts probably come out easier, but at least your finger's don't fall off with the cold.
~
Do you know how to anneal a coppper gasket before you fit it Liv?
Its so long since I saw a copper gasket I'm a bit hazy, I seem to remember that you heat it to blue and then quench it.
~
Is that right chaps?

Dave

[denisondc]

Sent: 3/8/2004 

Hopefully the copper gasket would already be soft, but yes, dropping the hot copper into water softens it. Letting it cool off in air makes it harden. The opposite of ferrous metals.
I removed all my studs, in favor of stainless steel bolts, because I wanted to be able to prevent the threads from siezing into the heads - I loosen and retorque them about each 2 or 3 years. I also put antisieze on them. Even if I didnt loosen them, I find they would need retorquing. Its a lot of bother on the side with the master cylinder in the way. It took me a couple of weeks of daily soaking in penetrating oil and wiggling with vise grips to get the studs out unbroken. denison

[Jupp318]

Sent: 3/8/2004 

Chaps,

  From my school days I seem to remember that it is better to quench copper in oil rather than water.  I think it is something to do with stopping the copper from getting so soft it goes out of shape. 

As for studs vs bolts, it was always the practice that you only ever used brass nuts on exhausts to stop them from rusting on.

Cheers Ian...

[mightybooboo]

Sent: 3/8/2004 

"As for studs vs bolts, it was always the practice that you only ever used brass nuts on exhausts to stop them from rusting on.Cheers Ian..."

Hmmm... a dumb guy question from BooBoo(like THATS something new,LOL)
How well do brass nuts do with torqueing down?
Thanks,
Booboo

[Jupp318]

Sent: 3/9/2004

BooBoo,

  Brass nuts are not new (unless recently purchased), but they do not seem to be so common these days, probably because everything is done as cheaply as possible.  The brass nuts that used to be used were something close to double the thread depth of a steel nut, therefore would torque down fine.

Cheers Ian....

[UluzYarx]

From: UluzYarx
Sent: 3/9/2004 12:24 PM

Hi Ian, I look forward  to seeing your pride and joy  as Sobyak's Superior Shindig, glad to hear you will make it.
~
Ian's quite right, we used to use brass nuts witj copper gaskets, thank you for reminding me Ian.
~
If you have new studs and new brass nuts, the new nuts torque down OK Booboo..
Old nuts or rusty pitted threads, forget it.
~
Most of us in the UK abandoned brass nuts for steel nuts and oxy-acetylene spanners unless we are rebuilding a vintage car where originality means big money.
Oxy is quite difficult to get to a V engine head manifold stud in a cab over I suppose?
~
Dave

[denisondc]

Sent: 3/9/2004 1:04 PM

I sort of like the oxy/acetylene spanner method also. I call mine the red-wrench. In small spaces you either have to remove whats in the way, or put up metal shields to control the collateral damage, and keep the water hose handy anyway. I have used brass nuts, but mostly as the 2nd nut on a stud, to stop the rusting of the otherwise exposed threads - the brass nut covers them up. For the first nut on a stud I use stainless steel, with antisieze, and do my torquing; for the strength. And normally I only use new brass nuts when reassembling an exhaust system. I always chase rusty threads with a tap too. Thats just me.
Between the anti-sieze, the stainless nuts, and the red-wrench, I am almost always able to get the exhaust system apart without using the cutting tip. denison 

[mightybooboo]

Sent: 3/9/2004

"For the first nut on a stud I use stainless steel, with antisieze, and do my torquing; for the strength"

An aside on stainless steel nuts and bolts.I replaced my old steel ones on my backup system batteries at home with stainless steel.It had a couple stainless on them, the steel ones had about corroded away;the stainless?... not a mark! Stainless are VERY nice and worth every penny,I use them now whenever I have an exposed setup of some sort.Not cheap early on,very cost effective long term.
BooBoo

[UluzYarx]

From: UluzYarx
Sent: 3/11/2004 

If you wish to pop over to the Uk Booboo I can solve your painful nuts problem, in two shakes of a lambs tail, with just a couple of house bricks.
~
It won't hurt a bit, as long as I keep my fingers out from between the bricks.
~
Dave

[westcoast redneck]

What I've done is to attempt to cool the manifolds by putting 3 inch dual exhaust.  Sound really nice too.  Had the manifolds shaved & copper gaskets as well.  So far so good.