Exhaust Manifold

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Mar 19, 2005 | 04:51 PM

raydioed

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From: raleigh/durham

EXHAUST MANIFOLD-300 6 cyl.\ PROBLEMS

I replaced the cracked xhaust man. on my 76 300 6 cyl with a used one off a 83 model and there is a 3/4" threaded hole on the bottom near the rear of it and I cant find any thing to fit it to plug it with.Anyone know what was originally screwed in there? Also the bolt holes on the flange are further apart than the holes in the collar that holds the downpipe up to the flange. Wondering if I can get one(collar or whatumaycallit) to match at the local auto part stores maybe. Just put a brand new 1bbl carb on it and it runs great and actually gets 19 to 20 mpg now...took the bench out and installed bucket seats and replaced the 3 on the tree with floor shift got rid of the big tires and put original size on and it steers lots better now(has man steering).
The "rag" is still sandwiched between the 2 flanges on the column but I lined up the bolt holes in top and bottom flange and bolted them together and no more slack! (may not be the rite thing to do but it works).

Mar 19, 2005 | 05:00 PM

oldhalftons

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From: Spokane WA

my manifold EGR hole is closed off with a 1" pipe plug.

Mar 19, 2005 | 05:02 PM

LxMan1

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From: Louisville,Ky.

Sounds like it could be for a smog pump tube. You can try a flange for a 83 model truck. or you can just let a local exhaust shop fix it. The headpipe may be a different diameter between the 2 years.

Mar 19, 2005 | 05:31 PM

raydioed

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From: raleigh/durham

I tried a pipe plug but the threads in the manifold are finer than pipe threads so I'll find a plug somewhere, and yes I think I will let the local exhaust shop solve the flange problem....

Mar 20, 2005 | 08:52 PM

MontanaFord

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From: Kalispell, MT

the hole in the bottom of your manifold is for the ERG that the 83 truck would have had....since you don't have any ERG on your truck, just find a bolt with fine threads that will fit, and plug it up...i went from having a manifold that had the ERG to having one that didn't have it, so in a sense, i gained some ground...the ERG just helps to burn excess fuel that didn't get burned the first time....personally, i think it's kinda a pain, but that's just me...

MontanaFord

p.s. i'd let the exhaust shop fix the flange problem, as you can sometimes mess things up (crack out the flange stud holes, etc) if you try and jerry-rig somethin together...that's why them boys have jobs...so they can solve your problems for you....

Mar 21, 2005 | 08:20 AM

MRStace84

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Joined: Jan 2003

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I removed the EGR tube on my 84, and had a pipe plug in it. If you have an old eGR tube. You can just cut the end of of it and crimp it.

Mar 21, 2005 | 06:17 PM

MontanaFord

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From: Kalispell, MT

to totally seal it off, run a weld bead across the crimped end of your egr tube...just a thought...don't want that little "wet-fart" sound that you can get with small exhaust leaks....

MontanaFord