Leak at thermactor plugs?

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
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Well I wondered if my thermactor plugs would leak when I put on some antiseize on the plugs and put them in the back of my heads...well today I went to check it and see if I could feel any blowing out by the plugs on the back of the heads...so I stuck my hand back there and didn't feel anything...so I stuck my finger over the plug and swear I felt it suck my finger to it when I had it resting against it...is that what it would do if there was a leak...would it suck in air where the old smog pipe went...

Also I have the thermactor plugs in the front of my engine as well...I guess I will need to pull those out to if there really is a leak...

So do I just put silicone on the threads and screw them in and let them dry...

What is an easy way to get those plugs out of the back of heads...hardly any room back there...
 
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bump - what would a leak at the smog pump provisions (where the plugs plug up) do? I know my check engine light is on...

What is an easy way to get them out of the back of the head...
 
5.0guy said:
it'll sound crappy and air will blow out. maybe you have the wrong size plug. did you try tightening the plugs down more?

Well it appears it is a very small leak...I swear I felt one of the plugs suck my finger to the head...(is that what would happen)...

It is only sealed with antiseize and antiseize isn't a sealer...

How can I get them in...I guess I could put them in more...but in case that works I don't want them to be in so far I can't get them out later...so I better do it right...is their something I can stick behind the head and back it out...

There the right size plugs...

Thanks for the reply
 
5.0guy said:
what kind of plug is it that you used? screw type or an actual plug..like a cork or something of that nature


I used the actual thermactor plug that is meant to plug up where the old smog pump lines go off the back of the heads...they screw in...

Anybody know how I can get them out easy from the back of the heads?
 
what size is the head? i thought some of them were flathead, that would be your best bet of getting it i think. i know a full length spark plug was too long when i was trying to plug mine.

in my experience, they like to be very tight. i had my plugs in just pretty tight at first. then i had an exhaust leak, it would not suck your finger to the leak though. i cranked them down more, and they were fine.

before pulling the heads, i would at least try tightening them more if you can :shrug: if you can tighten them more with the heads on the car, then you could probably get them off with a combination of pliers and whatever kind of head it has.

good luck
 
5 spd - I think you're dreaming. :)

The thermactor plugs from Ford have thread sealant on them in the bag. Why did you put Never Seize on them? You want them sealed - that's why Ford puts the thread sealer on the part. Never Seize is for something you want to be able to get back out. In any event, they are solid steel - if you've got them tight in the threads, they're not leaking.

Relax. Have a beer.
 
That port connects to the exhaust ports - a leak at the plug would sound/feel like an exhaust leak. Temp would be high - as in burned fingers. It wouldn't 'suck in' there.

Getting them out with the heads/engine in the car is very difficult. The only suggestion I've read that might work is take a penny (yes, that kind of penny) and insert it in the slots. Then try to get on the penny with channel locks or a pair of vice grips and turn it.

But I doubt they're leaking if they're tight. And if they're loose, they'd likely have vibrated out by now.
 
That is a positive pressure fitting there. It would blow out not suck in. It's basically a part of the exhaust system. You would feel a gentle puff puff puff of air and this sort of whistly exhaust sound like volkswagen bugs (the old ones) make. I would rtv around the outside if in doubt. An exhaust leak of such small magnitude that you question weather it exists wont affect anything at all.

Have fun!

Pete
 
Well how can I tighten them down...what size bolt can I put in there and use them to turn it inside?...I think there just not in there all the way...

Michael - I'm not dreaming :) ...there is some sort of air obstruction that isn't right...though really small...either sucking in or out...I can't tell..

I put antiseize on them so I could get them out easier if I ever needed them (sold the heads - and that way someone could get them out and hook up their emissions or just for any other purpose)...I didn't see anything on the plugs when I put them in...

I'm pretty sure I didn't put them in all the way...just flush with the head so nothing was protruding...

Oh and I don't drink :nice:

Oh and I'm not going to pull the heads for that...lol...I can get them (even with my big hands) out from the back of the head...I was just wondering if there was something I could (like a tool) use to get them out easy...the only problem with getting them out with a flathead is I dont' have the right one since it is in the head (flush) I would have to find the "perfect" size flathead..

So what kind of bolt can I thread into the plug to help screw it in further...and I can put a socket on in and start turning...

Thanks for the ideas...
 
use one of these deals..
____|
|

should be slotted on one end and philips on the other..or you could use a penny or dime(I've heard more about a dime). in either case, good luck!
 
5.0guy said:
use one of these deals..
____|
|

should be slotted on one end and philips on the other..or you could use a penny or dime(I've heard more about a dime). in either case, good luck!

Yeah I 've got one of those "deals"...

Well I'm going to try to tighten them in first...will they stop and hit something so I know there in all the way...

What bolt can I put in the back of them and tighten them in that way?
 
Just drive to the hardware store in the car. Take an assortment of bolts out and try them. It's got to be a shorter version of the long bolt that goes through the alternator bracket and a/c bracket -- same fitting on the front as the back. And no, the fitting won't bottom out on anything - it's tapered.

Oh - 'have a beer' isn't intended literally; it's a euphemism for Dude, chill. :)
 
Michael Yount said:
Just drive to the hardware store in the car. Take an assortment of bolts out and try them. It's got to be a shorter version of the long bolt that goes through the alternator bracket and a/c bracket -- same fitting on the front as the back. And no, the fitting won't bottom out on anything - it's tapered.

Oh - 'have a beer' isn't intended literally; it's a euphemism for Dude, chill. :)

Yeah I was thinking about taking out my alternator bolt (the one that goes thru the thermactor plug) and using it...

So if it doesn't bottom out on anything how do you know it is in all the way...will it "fall" anyplace?

I knew what you meant...I'm "chilled"...just asking questions :)
 
I think I mentioned it before - it's tapered. It'll simply get so tight you can't turn it anymore. You know what a tapered fitting is, right? Just like a fill/drain plug on a tranny or rear end.

The alternator bolt is gonna be way too long I suspect. It'll hit the firewall - you won't be able to get it started. Besides, you'll have to leave the bolts in. You'll need one for each side. As you tighten the fitting in, if you try to get the bolt out, you'll simply unscrew the fitting. Slow down there - think. :)
 
Michael Yount said:
I think I mentioned it before - it's tapered. It'll simply get so tight you can't turn it anymore. You know what a tapered fitting is, right? Just like a fill/drain plug on a tranny or rear end.

The alternator bolt is gonna be way too long I suspect. It'll hit the firewall - you won't be able to get it started. Besides, you'll have to leave the bolts in. You'll need one for each side. As you tighten the fitting in, if you try to get the bolt out, you'll simply unscrew the fitting. Slow down there - think. :)

Already ahead of you there...I was thinking" :) "...

I was going to put some antiseize in the threaded part of the plug where the bolt was going to thread into...and was going to hope it might back out on its own using the "taper" on the plug to hopefully hold it in...

If not I'll go to a store and keep the bolts in...there is probably 4 inches back there...

I missed the tapered part...