What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Exhaust Manifold/SMOG tube 'plug'??!

9

90blzr

1/2 ton status
Joined
Mar 25, 2001
Posts
3,027
Reaction score
0
Location
SO CAL
Anyone know where to get a plug for the exhuast manifold where the smog tubes 'used' to be? I have checked a few industrial supply places and they said 'you cant run without that smog stuff'. :rolleyes:

Anyways, long story short...I am ditchin the smog pump and tubes becaue my '90 never came with it in the first place.

I need to put a plug into the place where the smog tube used to enter the front of the exhaust manifold.

Anyone know the size of the fitting or what they are called exactly and where to get them??

Thanks!!!!!!
 
Mike,,, they are a standard tapered brass plug.... iirc I think the blzer was 3/8... they are available at any good auto parts store,,,even home depot...
somebody is blowing smoke on you....

cam
 
Yeah, I'd think even the "Help!" section of a chain auto parts store would have them.
 
camsk5 said:
Mike,,, they are a standard tapered brass plug.... iirc I think the blzer was 3/8... they are available at any good auto parts store,,,even home depot...
somebody is blowing smoke on you....

cam
Click to expand...

See thats what I thought, but thought MAYBE the threads looked a little different, should have just went with my gut. I was near a big industrial supply (they carry every nut and bolt imaginable) store. So I figured I'd go in. I show them the fitting from the manifold and they say..'oh thats some special type of fitting that only the manufacturer makes'. :confused:

So I go to another smaller place, they said the same thing.
Guess I'll run over to Home Depot after work :grin:
 
pipe plugs work,not exact thread though...

get some 1/4 inch NPT pipe plugs at home depot or hardware store--they are not the perfect thread,as the stock fittings are either "straight" pipe thread,not "tapered"--or machine screw thread ,either SAE fine thread (9/16x20?)or Metric,about 14mm...but the NPT plugs go right in and seal well--I' got 6 in my 305 I ditched the "flute pipes" on too!.. :crazy: I've seen spark plugs forced into them holes too--but dont put any plug wires on them,unless you like replacing mufflers... :blush:
 
go to your local mom and pop hardware store..

go to aisle with all the steel water pipe threaded fittings, look in bins with the small male threaded piep plugs,

one of them is the ones to use,

its real easy and super cheap
i dont know why ppl have such a hard time with this one......

its really easy.......
 
Okay, went to another big bolt house.....1/2" is to small....3/4" is too big. Took a 7/8" fine nut and it goes on about 1/2 a thread. Took a Metric...I think 20 and it goes on a little better. Measured the threads, etc with a guage.
Threads are 18 and the diameter appears to be metric. So it IS a wack/special size. :mad:


So I guess my options are A) buy a bit and tap and drill them out to 3/4" to put a pipe plug in them or B) find some manifolds with no previsions for smog equipment.

This sucks...why isnt anything 'simple' anymore. :dunno:
 
diesel4me said:
get some 1/4 inch NPT pipe plugs at home depot or hardware store--they are not the perfect thread,as the stock fittings are either "straight" pipe thread,not "tapered"--or machine screw thread ,either SAE fine thread (9/16x20?)or Metric,about 14mm...but the NPT plugs go right in and seal well--I' got 6 in my 305 I ditched the "flute pipes" on too!.. :crazy: I've seen spark plugs forced into them holes too--but dont put any plug wires on them,unless you like replacing mufflers... :blush:
Click to expand...


These manifolds dont have the ones on every tube...just one at the front, thats it.
 
Must be metric...

It must be a weird metric thread or something... :thinking: --if you have torches or a welder,I have made the original fitting into plugs by cutting the pipe off it,and brazing or welding the center shut--crude but effective,and no endless trips searching for plugs!--I haven seen one I couldn't put a pipe plug in yet though--must be lucky I guess... :crazy:
 
I couldn't find the right threads either, so I cut the tubes about 1" out from the plug and threaded a bolt into the tube I.D. to seal it up.

This worked fine for a year or two until I got headers.
 
mike... I know I did this on my blazer... I walked in to the auto parts store and walked out with them and they fit fine.... they were american...not metric... so perhaps they changed the later ones
is this something you want to send up to me and have me just weld it up?

cam
 
Looks like thats what I'll have to do.

I guess I could also just weld up the hole in the fitting thats on there now.

Nevermind, its stainless. Hmmmm....could I just put some epoxy type stuff in the fitting to make it a 'plug'? Like the stuff you use for sealing up radiators or other high heat application? Sounds kinda ghetto, but I really dont wanna replace the manifolds just because of this damn hole. Its only one one each side too.

Not in the manifold, but in the fitting, that way I could still remove it if I have too? (though I dont see why I would ever have too.)
 
camsk5 said:
mike... I know I did this on my blazer... I walked in to the auto parts store and walked out with them and they fit fine.... they were american...not metric... so perhaps they changed the later ones
is this something you want to send up to me and have me just weld it up?

cam
Click to expand...

Didnt seem your post before I made my last reply. Yeah, I think the later ones (89+?) they must have just used a different design so you could not easily do away with the smog stuff.

Maybe I will do that. Cut the ned of the line, slide the fitting off and have them welded up like I mentioned above. Not able to weld stainless down here though and a shop would charge an hour minimum for 5 minutes of work.

You can weld stainless cant ya cam?
 
yes you can...

You can weld stainless with the right rods--but I've used 6011 rod with my arc welder on those types of fittings to plug them off with no problems...or you could braze them,brass works good on stainless too..

They do make hi-temp epoxy like "pyro putty",but I doubt that stuff will last very long--for the price of that stuff you could buy a pipe tap,(or borrow one, even better!)and the pipe plug at home depot ,cut new threads in the manifold,screw it in and be DONE!! :crazy:
 
I didnt mean 'can you weld stainless'....I was actually asking if CAM can weld stainless :grin: I think he has the stuff to do it if I remember right. I thought when I was at his house he mentioned it.

Tap and bit and all would be about $65. More than I wanted to spend on some friggin plugs.
I'd rather buy some high temp epoxy and fill them up for $5 at a time than. Or else just find some other manifolds.
If I could get someone to weld up the fittings, that would solve everything :grin:
 
You must log in or register to reply here.

Latest Posts

Top Bottom