Exhaust manifold gasket - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Chief_Wiggum · 01-23-2012, 04:11 PM

I have a '77 K10 that I'm slowly trying to fix up. It has a 350 with the stock cast iron manifolds. The exhaust system looks original as well. It has a bad exhaust leak at the driver's side manifold collector where it bolts to the exhaust pipe. I got some new donut gaskets. Passenger side fit correctly, but the driver's side didn't have a gasket on it. Instead, it has what almost looks like a flare fitting with a nipple cast onto the manifold and the flare on the exhaust pipe. Does anyone know if this junction has a gasket, or is it supposed to be metal to metal? If so, how the heck do I seal it up? Thanks for the help.

85Bowtie · 01-23-2012, 07:35 PM

Not sure on GM, but on Mopars they never used exhaust gaskets. Just the manifold to the head. However, after years of heat cycling and stress, you probably should use a gasket if you can find one, which shouldn't be hard at a parts store.

Chief_Wiggum · 01-23-2012, 07:49 PM

Yeah, I replaced the manifold to head gaskets, but these are the gaskets at the collector where the manifold meets the exhaust piping.

**old Rusty C10** · 01-23-2012, 08:10 PM

IIRC there is a round gasket in there that is kinda thick its been a while since ive done any exhaust work myself... i usually farm it out now

85Bowtie · 01-23-2012, 08:46 PM

Nevermind, I thought you were talking about the head. Just get the donut gasket for it like mentioned.

donut · 01-23-2012, 10:08 PM

What does the parts "book" show? i don't remember one in mine, but looking at the "nipple", I would think that the donut would fit over it and seal the bell on the head pipe.

I'll take a look tomorrow. My manifolds for the '86 are in the bed along with the pipes to connect them.

raceman6135 · 01-24-2012, 12:30 AM

This is how one of my truck's gaskets is:

As you can see, the gasket has a metal portion that fits into the exhaust manifold, and the other side (which connects to the exhaust pipe) has a taper. The taper mates to the exhaust pipe taper, like the ones on this pipe:

Chief_Wiggum · 01-24-2012, 11:31 AM

raceman, that's it! Thank you for the pictures. When I took the exhaust pipe off, I thought that piece was cast into the head. I'll have to try and bash it out of there. Do you know if Napa or O'Riellys has this?

motornut · 01-24-2012, 11:47 AM

may want to pick up some brass nuts for those studs
sure makes it ez to remove them later

donut · 01-24-2012, 08:44 PM

Quote:

Originally Posted by Chief_Wiggum

raceman, that's it! Thank you for the pictures. When I took the exhaust pipe off, I thought that piece was cast into the head. I'll have to try and bash it out of there. Do you know if Napa or O'Riellys has this?

I picked one up at O'Reilly's last week.

Chief_Wiggum · 01-25-2012, 11:42 AM

Thank you, much appreciated.

01-23-2012, 04:11 PM	#1
Chief_Wiggum Registered User Join Date: Jan 2012 Location: Flagstaff Posts: 7	Exhaust manifold gasket I have a '77 K10 that I'm slowly trying to fix up. It has a 350 with the stock cast iron manifolds. The exhaust system looks original as well. It has a bad exhaust leak at the driver's side manifold collector where it bolts to the exhaust pipe. I got some new donut gaskets. Passenger side fit correctly, but the driver's side didn't have a gasket on it. Instead, it has what almost looks like a flare fitting with a nipple cast onto the manifold and the flare on the exhaust pipe. Does anyone know if this junction has a gasket, or is it supposed to be metal to metal? If so, how the heck do I seal it up? Thanks for the help.

01-23-2012, 07:35 PM	#2
85Bowtie Registered User Join Date: Mar 2009 Location: TN Posts: 410	Re: Exhaust manifold gasket Not sure on GM, but on Mopars they never used exhaust gaskets. Just the manifold to the head. However, after years of heat cycling and stress, you probably should use a gasket if you can find one, which shouldn't be hard at a parts store. __________________ '69 Dodge Charger R/T 440, 727, 3.55 Sure Grip '68 Plymouth Road Runner 383, 727, 3.23 Sure Grip '89 Dodge Diplomat ex cop car 408, 727, 3.55 Sure Grip '77 Dodge Monaco ex cop car 440, 727, 2.71 '79 Dodge 'Lil Red Express pickup 360, 727, 3.55 Sure Grip '12 Dodge Challenger SRT8 392, M6, 3.92 '85 Chevrolet C-10 SWB 2wd 305, TH350, 2.73

01-23-2012, 07:49 PM	#3
Chief_Wiggum Registered User Join Date: Jan 2012 Location: Flagstaff Posts: 7	Re: Exhaust manifold gasket Yeah, I replaced the manifold to head gaskets, but these are the gaskets at the collector where the manifold meets the exhaust piping.

01-23-2012, 08:10 PM	#4
old Rusty C10 Robert Olson Transport Join Date: Oct 2002 Location: recent transplant to NC USA Posts: 20,287	Re: Exhaust manifold gasket IIRC there is a round gasket in there that is kinda thick its been a while since ive done any exhaust work myself... i usually farm it out now __________________ Bob 1951 International running on a squarebody chassis "If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board" http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!) PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport Live each day to the fullest.. you never know when fate is going to pull the rug out from under you... I hate cancer!!

01-23-2012, 08:46 PM	#5
85Bowtie Registered User Join Date: Mar 2009 Location: TN Posts: 410	Re: Exhaust manifold gasket Nevermind, I thought you were talking about the head. Just get the donut gasket for it like mentioned. __________________ '69 Dodge Charger R/T 440, 727, 3.55 Sure Grip '68 Plymouth Road Runner 383, 727, 3.23 Sure Grip '89 Dodge Diplomat ex cop car 408, 727, 3.55 Sure Grip '77 Dodge Monaco ex cop car 440, 727, 2.71 '79 Dodge 'Lil Red Express pickup 360, 727, 3.55 Sure Grip '12 Dodge Challenger SRT8 392, M6, 3.92 '85 Chevrolet C-10 SWB 2wd 305, TH350, 2.73

01-23-2012, 10:08 PM	#6
donut Registered User Join Date: Aug 2009 Location: S.C. Posts: 1,593	Re: Exhaust manifold gasket What does the parts "book" show? i don't remember one in mine, but looking at the "nipple", I would think that the donut would fit over it and seal the bell on the head pipe. I'll take a look tomorrow. My manifolds for the '86 are in the bed along with the pipes to connect them. __________________ '86 C-30 dually, 454/tbh400 '73 K-20 350/350/205 (sold ) I'm kinda like duct tape- no real purpose, but handy to have around.

01-24-2012, 12:30 AM	#7
raceman6135 Dino burner Join Date: Nov 2002 Location: Calgary, Alberta, Canada Posts: 602	Re: Exhaust manifold gasket This is how one of my truck's gaskets is: As you can see, the gasket has a metal portion that fits into the exhaust manifold, and the other side (which connects to the exhaust pipe) has a taper. The taper mates to the exhaust pipe taper, like the ones on this pipe:

01-24-2012, 11:31 AM	#8
Chief_Wiggum Registered User Join Date: Jan 2012 Location: Flagstaff Posts: 7	Re: Exhaust manifold gasket raceman, that's it! Thank you for the pictures. When I took the exhaust pipe off, I thought that piece was cast into the head. I'll have to try and bash it out of there. Do you know if Napa or O'Riellys has this?

01-24-2012, 11:47 AM	#9
motornut 78K & 79C Jimmys Join Date: Nov 2009 Location: Ottawa Ont CANADA Posts: 7,901	Re: Exhaust manifold gasket may want to pick up some brass nuts for those studs sure makes it ez to remove them later __________________ John 1978 GMCJimmy4X4-350/203 1979 GMCJimmy4X2-305/350

01-25-2012, 11:42 AM	#11
Chief_Wiggum Registered User Join Date: Jan 2012 Location: Flagstaff Posts: 7	Re: Exhaust manifold gasket Thank you, much appreciated.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.