Plugging Smog holes on Manifolds

[shadowfax101]

I think this is the route I am going to take first. I know I have a leak coming from the real manifold on the passenger side. I can not tell if it is coming from the smog tubes or the manifold it self. I figure I want to do this anyway. So how is the best way to plug the holes. I was thinking maybe undo the bolt take off the tube and but the bolt back in? I have no idea that is why I need help...
I am planning on doing this in the morning so any help would be great.

[Brown Bear]

If you just put the bolts back in, the holes inside the bolt will be exposed. I filled the holes with jb weld, works pretty good.

[Quadra-Clint-]

Putting the original bolts back on wont work as they are hollow with a T so dont tear it up till you either have solid replacements or are willing to take off the mani's and weld em up.
My first go at it was to replace with solid bolts wich I scored from a hardware store,fine thread if I remember correctly.Next was the perma fix,with manifolds off I turned the OE bolts on till the heads snapped off then arc welded the hole shut forming a little dome :D kinda looks better IMO.

[Stuka]

I Have been unable too find plugs for my manifolds...nothing has worked for me :/

[Quadra-Clint-]

Hardware store brotha.

[shadowfax101]

So you just take the stock bolt to the hardware store and match it up and all will be good? If I can not find one I will go with the JB weld. I hope I can find the bolt at the store..

This might be easier than I thought. now I just hope I do not break a bolt. These do not seem to be as tight as the manifold ones are

[Quadra-Clint-]

Also make sure they are a little shorter,so as to make up the diff of the air tube ring.Yea careful takin em off.I'de go out and PB Blaster em tonite.

[shadowfax101]

One step ahead of you, I put the PB on there about 2 hours ago. I am going out to soak it again before bed..

[Bob Barry]

They are 9/16"-NF (fine-thread) bolts. You'll have to cut them down to about a 1/2" long (3/4" were the shortest I could find, so I ran a nut down, held them with some vise-grips, and used a cutoff wheel in an angle-grinder to get them to size).

If you break them off, grind the broken surface flat, then tap the hole for a 1/4" Fine-thread bolt, use some high-temp silicone on the threads, and plug it that way.

I've found the shock of an impact is less likely to break them off than regular old constant leverage.

[Stuka]

Mine are in no way fine thread, I have looked everywhre..I cannot find one that will work. JB weld wont work, I gota make sure i cann put smog back in it one day.

EDIT: I amm a "Master Mechanic" now smile.gif

[ April 28, 2002: Message edited by: Stuka ]</p>

[Crazy_Jeepman]

Yup I have used the 9/16"-NF, may not look like it, but try one you may get surprised. ;) I have my 79 blocked off with them, as well as a set of 89 Manifolds. All used the same banjo bolt anyhow. ;)

[Stuka]

9/16 is to large for my manifolds...will not thread in

[Chero77]

On my '77 the banjo bolts were 9/16 fine thread. I cut down standard 9/16 1" bolts down to 1/2 long.

Stuka, whatever size your bolts are, since your in CA, I don't know if I would bother with this. I did it thinking I would never sell my Jeep. Well, now I am thinking of selling it and am in the process of putting all the smog stuff back on.

[Gladi8r]

I have also used the 9/16 NF. Works on my 88 GW---been that way for almost 10 years with no problems :D :D :D

[Iron Horse]

Just go pull another set of manifolds and weld'em up. Mount them up, Viola! You're done. That way you've got you're original set-up for future use.

[Bob Barry]

<blockquote>quote:</font><hr>Originally posted by Stuka:
9/16 is to large for my manifolds...will not thread in<hr></blockquote>

Your manifolds threads may have "grown" over the years with rust and corrosion. I bought a tap specifically to clean out these threads. All the manifolds I've done these bolts on (about a half-dozen to a dozen, from 1978 to 1988) have been 9/16"-fine thread; check the threads on the banjo bolts you've pulled out.

I'd wager a spare set of '80-up manifolds that Jeep never changed the banjo-bolt thread size during that period.

[rhinojeep]

I replaced mine with a metric plug. It is a M14/1.5. I got them at Carquest Parts store. They came with a nylon washer. I did not use the washer but did use a high temp gasket sealer.

I replace all but one. Be careful taking off the manifold bolts. Since they are hollow they are easy to wring off. I rung one off and still have not found a way to remove it. I tried a screw extractor with very little success. I finally just found a screw that I jammed in the hole. (works for now) Any tips on removing the bolt.

[chrisnsarah]

I heard that a spark plug thread is the same. I remember reading this somewhere, but don't remember the source. If that's the case, you can thread old spark plugs in there. Look really weird though. Haven't tried it myself.

[Iron Horse]

Hey Rhinojeep,

If you can't get your broken bolt out with a screw extractor ("easy out"), then you'll need to drill it out and retap the hole with the next larger size bolt. However, did you try to extract it with the engine block nice and warm? You might try that.....heat can be a powerful tool when working with rust/crusty stuff.

[R Kriz]

Hey there, I have a '85 J10 with the 360. I broke off the rearmost banjo bolt in the pass. side. After taking the manifold off and applying heat with a oxy/acet torch the broken piece came out with ease. If nothing else works, give it a try. A bit of head does amazing things with rusted bolts.
Good Luck,