5/8 x 1" or 1.5" coarse thread bolts with a copper washer to seal.

 

Thanks guys....big help.
This 92 f-150 I have only has 72,000 original miles and I'm in the process of trying to get it running right and quiet. It was my fathers pride (barely driven) until he passed last year. I bought a cap for it and it has new tires. I need to keep this thing in descent shape.
Crossover tubes rotted, Exhaust flanges are leaking, e.g.r. tube is rotted out. engine light on and code is for egr.
I put new plugs/wires/cap rotor to start.
I just relaced the exhaust from cat back. It was rotted out. I put a single exhaust out the pass. side rear. I want to have the flanges replaced and the heads plugged up now. I also have the egr tube, valve, and sensor to replace....then hopefully it will be quiet with no codes!

 

Just to add to the mystery of the crossover tube, my 89 F250 5.8L came with one. Of course it is blocked off now.

 

I'm wondering if I will have to source one for the 96 5.8 that I am going to be getting from strokin_tatsch. I still have to pass sniffer test here.

 

The other link showed 5/8 -11 "thermacter plugs" I suppose a bolt would do just about the same thing...thanks for the replys......I do have a question.

Does this bolt you are describing thread into the head itself?
I can see there is a small block bolted to the each head, the air tubes used to come off these blocks(air tube was rotted,gone, Now left with a hole in each block the size of the tube approx 5/8) Wondering if your speaking of plugging these blocks? or plugging the heads.
Does the head actually have a 5/8-11 hole behind these blocks?

Thanks
Dan

 

The plug or bolt goes into the head after you remove those blocks.. which are held on by a smaller bolt that will leave a hole that doesn't need to be plugged.

 

Thanks! I bet those threads inside the hole in the head are crrrrussssty.
Will have to try and run a tap through....oughta be fun.
Trying to do this whithout removing engine! LOL
Not much room back there.

Thanks again!!