If the plug isn't physically hitting the manifold there's a way to get it out.  It may mean making a special socket/wrench though.  I had to make one to install/remove #7 & #8 plugs once I went to JBA headers.  I took a 13/16" plug socket, removed the rubber, cut the portion with the drive square off leaving about 1.5" of the socket, and then welded a 4" piece of 3/8" round bar to it at an angle.  Works like a charm.

If there's an interference issue you may have to use or make a crows foot style wrench, or take a socket and cut the side out of it that interferes (like how an oxygen sensor socket is done). 

when you break it lose, use a spark plug boot or piece of rubber hose to twist it out straight
 

DC wrote:

Some where I had a plug socket that had a hex at the top I was able to get it on the plug and use an open end wrench or crowfoot on it to do the job. It was a Craftsman socket I ground a little off of both ends to get it to fit in the cramped area.

I got one!!!  Use it a lot.
6sal6
 

Thanks Rufus, because of your link, I found this 

https://www.amazon.com/gp/product/B0018U295K/ref=ox_sc_saved_title_1?smid=AM0TJKCE8MD21&psc=1


I haven't yet removed the exhaust manifold, so we'll see if this works. Otherwise the mustang is running typical snafu. Sounds great, idles great, starts up solid.... and the temp gauge gets to over halfway hot and boils over after 15 minutes of idling. 

Next purchase is going to be one of those combusiton gas leak detection kits to attach to the radiator, and see if its a head gasket or if something is clogged, which I've only got a small hope for that.

Last edited by JeffK (5/30/2018 2:16 PM)

..... blink.....

I suppose I ought to do that first. I'll see about that tonight.

Pulled the thermostat, there was a fair amount of scale on the upper hose, however the thermostat itself was clean. Once I placed it in boiling water, it opened immediately.

Should I be checking the coolant for exhaust gas, at this point?

I have a basic 4 blade fan, 2 or 3 core radiator with a metal fan shroud. The water does move around in the radiator, don't really notice bubbles, unless I squeeze the upper radiator hose, then I get a bunch. The oil while extremely dark is translucent, but it does smell of gas.

The exhaust, its slightly smokey under medium throttle, but I also have not run the car in the last 2 years. So I'm not sure if its still trying to clean itself out or if its coolant. Btw I'm just using water. There is some scale in the radiotor
 

The shroud is good, but the 4 blade fan's not doing you any favors.  Also, how close is the fan to the radiator?  There were a ton of different fan spacers and I've seen the fan everywhere from 1/2" to 3" away from the radiator in these cars.  You want it about 1" away.  Any farther and it doesn't move air through the core effectively, even with a shroud. 

BUT, I'm assuming this issue is new.  In other words, 2 years ago when you parked the car it didn't do this?  Or is this why you parked the car 2 years ago?

I've had the car for about 12yrs. Once I put on the shroud, I was able to drive it around in the summer with very little fear of overheating, a few years ago it got bad, it gets over 100 in the summer out here, last few times on the freeway, it would boil over as soon as I pulled over for gas, so.... it got parked until now, when I feel I had a budget to deal with it.

The fan blade is about 2" from the radiator, its mostly inside the area of the fan shroud. I recall the shroud used to make the difference between overheating or not. Last week it was 75 degrees , sitting in the driveway and it boiled over after 15minutes of idling.


 

I'm sorry to hear that... did you try the pass-through socket I suggested?  It was the only thing that worked for me to get to a spark plug around one of my header tubes.

I've tried the skinny socket, located on post 8 of this thread. I couldn't even get that to slip between the header and the spark plug. I would also have zero clearance for a pass through. I think what I must have done years ago was I put the spark plug on, and then the headers. And I got lucky that I have no exhaust leaks and didn't damage the plug. So... this time I'll remove the header and trim it and never have this problem again.

When in doubt, grind, cut, and weld.  You can always turn the socket down on the OD with a belt sander, grinder, or shaper (or a lathe if you happen to have that kind of shop).

Hard to believe that there's an interference issue with HiPo manifolds (stock), yet I can get the plugs in and out with my JBA headers.  Yes, I did have to make a tool to fully loosen/tighten two plugs, but that was a clearance issue on the back end; not a diameter issue.  It resulted from how two tubes ran essentially behind the plugs, yet I've plenty of room for the plug boots.  Its literally just a case of where there's no room for the head of the ratchet, and the socket is about 5/8" too long. 

It makes you wonder what they used for a pattern when manufacturing the new manifolds.  Clearly they aren't a great copy of the originals.