Inline 6 help

[L&L70]

On both ends of the exhaust manifold, do I have broken studs or are those locating pins? I think it is a 250 since the motor mounts are in inline with each other. Thanks guys

Matt

[car66]

on the inline 6 in my truck, they look like they are locating pins

[PanelDeland]

Locating pins.They work OK on a stock truck but I would change to bolts/studs if I had the head off or was putting headers on.Just for peace of mind.

[L&L70]

Im sure the other will break this weekend, but at least Im not starting in the hole! Thanks Alot I had read that the 80's inline 6 had the one peice intake/exhaust gasket, but I think the parts store was showing the same gasket for all years. Just trying to make sure they are ordering the right part for me.

[sixtyeightchevykid]

the intake and exhaust gasket is one piece..

[RichardJ]

'79 and later 250 had the Pulsair head with integral intake manifold and 2bbl carb.
The 292 and earlier 250 and 230 with separate intake manifold and exhaust manifold used a one-piece gasket, but there is a three piece gasket available.
Felpro's intake gasket has their Blue-Line. The two piece exhaust has a separate part number.

http://www.summitracing.com/parts/FEL-1257/

http://www.summitracing.com/parts/FEL-1448/

I tried these gaskets when I first put the headers on my 292.
THE GASKETS ARE CRAP. At least for use with headers. The exhaust lasted a week. They are crap and overpriced.
Felpro does have a one-piece, but is for stock cast exhaust.

The end studs are threaded into the head. Soak with your favorite penetrant for a day and turn out with a good vice grip with good sharp teeth. You would be doing yourself a favor if you install studs in all the manifold bolt holes.

[L&L70]

So the end (locating pins/studs) are threaded? If they are threaded, I would like to attempt to pull them and install studs. The rest of my manifold bolts are already studs that go over the "cradle" that catches two ears at once. I ordered a one piece MrGasket from oriellys (worth a damn?) Thanks guys for answering questions on a motor I have never had before.

['68OrangeSunshine]

Originally Posted by L&L70

So the end (locating pins/studs) are threaded? If they are threaded, I would like to attempt to pull them and install studs. The rest of my manifold bolts are already studs that go over the "cradle" that catches two ears at once. I ordered a one piece MrGasket from oriellys (worth a damn?) Thanks guys for answering questions on a motor I have never had before.

Yes the guide pins are threaded 3/8"-16 UNC. They will back off after a good soaking with PB Blaster, or Liquid Wrench. Grab them with a good ViceGrips and twist off counter-clockwise. If you're using a stock manifold they might be OK, but if you want to run headers on your L6, then pull them off because headers will never seal properly with the stock pins on.
I use studs 3/8" -16UNC on one end and 3/8" -24 fine-thread on the other.

[L&L70]

Well I got the manifolds off and my exhaust has 6 cracks in it. While I attempt to locate another one, I will try and pull the pins. Is there any good ways to delet the heat riser plate inside the manifold?

[old Chevy guy]

I have a 250 intake and exhaust manifold for sale in a thread on the parts board if you are interested. One of the studs is broken where the pipe bolts up but Im pretty sure I can get it out if your interested at all. The thread tittle is parting 68 250

[PanelDeland]

I wouldn't suggest deleting the heat riser plate.It helps with cold weather running and starts.

[L&L70]

I am assuming that a used manifold will have a sloppy heat riser shaft. I dont like exhaust leaksand just figured I would tip the riser plate up and plug weld the steel shaft to lock it. I guess if the one I get is tight and the spring is good, I would just keep it.