Author Topic: Exhaust manifold and clutch help  (Read 4008 times)

Offline lt1kicker

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Exhaust manifold and clutch help
« on: August 28, 2007, 11:51:46 AM »
Look for some guidance on two different issues here-
This fall I plan to do a tuneup on my '79 Scotty.  It should not be real difficult but at the same time I want to replace the exhaust manifolds.  They are rusted beyond belief and are cracking pretty bad, to the point that more exhaust smoke comes from under the hood than out the tailpipe.  I want to replace them asap as the bolts are pretty well rusted as well.  What is a good replacement, and is it common for these bolts to snap off?  This is a 350 motor, btw.

Secondly, I've noticed that it feels like my clutch is slipping under hard acceleration.  If I get on it pretty good, and go to shift, it feels like it's slipping before it catches.  Now, I haven't had any "grinding" noise or anything upon shifting, but I don't know what else could cause this.  It is a four-speed manual, and the truck is four wheel drive.  If i have to swap in a new clutch, will it be necessary to drop the tranny and transfer case? 
Aj
1979 Chevrolet Scottdale 4x4, 350, 180k
1994 Caprice 9C1, LT1, G80
1995 Caprice 9C1, LT1, FOM9C1
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Offline team39763

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Re: Exhaust manifold and clutch help
« Reply #1 on: August 28, 2007, 01:58:26 PM »
I'm not 100% sure, but I think you could snag some longtube headers pretty cheap.  I sold my 4month old Hedman headers for $60 and I gave away the summit headers that came with my truck.  Breaking off bolts isn't too big of a problem(that I know of), but if it happens, there's a few cheap ways to get'em out. 

Offline Lt.Del

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Re: Exhaust manifold and clutch help
« Reply #2 on: August 28, 2007, 02:16:01 PM »
Yes, you have to drop the transmission to replace the clutch disc.  Might as well get a new pressure plate, throwoout bearing.  Check your flywheel for unweven surfaces.  May have it turned.

Exhaust bolts, yes. it is common for them to  snap.  Warm up your engine before loosening the bolts.  heat helps them come out easier. Replacement....stainless steel bolts.

 

Offline VileZambonie

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Re: Exhaust manifold and clutch help
« Reply #3 on: August 28, 2007, 02:18:53 PM »
The shorty headers for the 88 up body style will fit nice you just have to plug the O2 bungs and maybe grind a small notch where the bung is near the frame. Before you pull your manifolds soak everything good with penetrating oil. Use 6 point sockets and make sure you're holding your ratchet square so you don't round those rusty bolt heads off.
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Offline Captkaos

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Re: Exhaust manifold and clutch help
« Reply #4 on: August 28, 2007, 02:36:16 PM »
Yes, you have to drop the transmission to replace the clutch disc.  Might as well get a new pressure plate, throwoout bearing.  Check your flywheel for unweven surfaces.  May have it turned.

If you replace the disc, get a new assembly (clutch, pressure plate, throw out bearing) and have the flywheel resurfaced.  If you are going to pull it apart you might as well save yourself the headache of having to do it again sooner.

Offline Blazin

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Re: Exhaust manifold and clutch help
« Reply #5 on: August 28, 2007, 09:27:53 PM »
I go ahead and cut the bolt heads off if they are that bad, Then remove the manifold by sliding it off of the bolt shaft. Then you can soak the bolt with PB Blaster were it counts. At the point the threads enter the head. Plus if you need to heat the head your not wasting time and energy heating the manifold too. Use Vise Grips, Vise Grips not cheap imitations with good sharp teeth on them to turn the bolts out. Have done this many times and never broke one off yet. I have however broke them off screwing around trying to get them out with the manifold on.
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Offline lt1kicker

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Re: Exhaust manifold and clutch help
« Reply #6 on: August 29, 2007, 09:50:39 AM »
Thanks for the tip.  Whats the best method for cutting the bolt heads off? 
Aj
1979 Chevrolet Scottdale 4x4, 350, 180k
1994 Caprice 9C1, LT1, G80
1995 Caprice 9C1, LT1, FOM9C1
www.fallenofficermemorial9c1.org

Offline Lt.Del

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Re: Exhaust manifold and clutch help
« Reply #7 on: August 29, 2007, 11:40:20 AM »
Quote
Whats the best method for cutting the bolt heads off?

Got a good grinder?  You may have to but a few cutting wheels, but they are real cheap.  I have a 4.5 inch dewalt grinder and love it.    You can use Blazin good advice if you chose. But, you may be amazed at how easy some of these bolts will come out when the manifold is warm. Vile has a good point as well with the 6 piont sockets.  I don't use taiwan stuff either...craftsman.
 
If you have a 1/2 inch drive ratchet I'd use that for more leverage--and perhaps put a pipe around the handle for even more leverage.

     

Offline lt1kicker

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Re: Exhaust manifold and clutch help
« Reply #8 on: September 05, 2007, 04:44:26 PM »
Thanks for the tips.  Back to the clutch, I spoke with a mechanic today who is resto'ing an old Ford Hi-Boy and I told him my tranny seemed to slip.  He said it didn't sound so much like the clutch was bad, but maybe it was low on hydrolic fluid?  Any chance that's the problem>
Aj
1979 Chevrolet Scottdale 4x4, 350, 180k
1994 Caprice 9C1, LT1, G80
1995 Caprice 9C1, LT1, FOM9C1
www.fallenofficermemorial9c1.org

Offline zieg85

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Re: Exhaust manifold and clutch help
« Reply #9 on: September 05, 2007, 05:24:55 PM »
Thanks for the tips.  Back to the clutch, I spoke with a mechanic today who is resto'ing an old Ford Hi-Boy and I told him my tranny seemed to slip.  He said it didn't sound so much like the clutch was bad, but maybe it was low on hydrolic fluid?  Any chance that's the problem>

If it were low on hydraulic fluid your pedal would be real low and you would probably be grinding gears and may not be able to put it in gear at all.  If your clutch pedal it all the way at the top when you are letting out the clutch then it is time to replace it.
Carl 
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1986 C10 under construction
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Offline Blazin

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Re: Exhaust manifold and clutch help
« Reply #10 on: September 05, 2007, 09:04:00 PM »
If you have a liquid clutch on a 79 it would be pretty rare. First fluid clutches I know of is 85. As far as the bolts I assumed you had allready tried to get them out thats why you were looking for alternate methods. I too would try to get them out first, but just remember if you break one off 99% chance it will break flush with the cylinder head. Then you won't have anything to grab onto. It will be a drill and easy out for sure.
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