Hey guys new to the fourm here names adrian.
I've got a 1991 f150xlt 4.9 5speed 2wd the other day I was driving and it blew a pipe.
The pipe I belive is part of the smog system anyways the pipe is the drop down tube into
Piston num 6 the privous owner I belive tried deleteing the system but didn't delete the pipe beside the head and the drop tubes down I'm wanting to go ahead and remove it all but I can't find what size the whole is or what I even need to block the wholes off with any help would be greatly appreciated
Truck is a daily driver 300k dual tanks

 

I have seen them with plugs in the exhaust manifold. Have also seen them with the tubing bent over and pinched by a pair of vise grips that made a pretty good seal. Cannot offer advice on how to disable emission controls, but can tell what I have seen others do.

 

Ok I mean its on the intake side where it takes air from exsuat puts it threw a pump turned by the belt then back into the head threw like an air rail the pipes aren't long enough to bend and clamp but thank you for your help

 

If you try to remove the rusted thru piece from #6 cyl you can probably match the nut with something available from any auto supply store. If soaking it with a good penetrating oil doesn't work they usually come loose easier when hot. That pollution control system had more solenoids and check valves than you could shake a stick at. It was called the Thermactor system. Worked OK when it worked, but had a high failure rate with all the extra junk.

 

Thanks hanky for your help going try and fix it this weekend