the piece that holds the y pipe to the manifold on my 84 rusted out and fell apart on me creating a massive exhaust leak. i tried to fix it but i think i made it worse. i cut the pipe at its lowest point where it comes across to the drivers side and slipped on a new part. but when i tried to get the old bolts out they both snapped off. Am i totally screwed at this point or is there some way to recover before i have to admit defeat and take it to a pro. i've never used a tap and die set before is this something that would work on? Also there is some part in there that i've never seen before. it slips in between the manifold and the y pipe. Lmc truck is calling it a "heat riser" http://www.lmctruck.com/ICATALOG/FD/full.aspx?Page=105 if i did that right it should be the link to it. Any clue what its for? or if its important? it has a lever that can open and close a flap inside the pipe.

see if you can drill out the bolts and then just use new ones, unless you stock manifolds are that bad, then i would sugest switchin to headers.....i don't know what that is, but whats the point lol

Ok, you can do a few things at this point. One - Drill out the two places where the exhaust manifold bolts were and simply use a long bolt with lock washer and nut. Two - Drill a hole dead center of the broken stud and use an easy out to back it out. While doing this you will have to soak the broken studs with a penatrating spray. Three - Find another set of used stock manifolds. Four - Go with shorty headers.

My advise would be to go with the shorty headers, however if you would rather the stock manifolds I do have a set. --Vince

that was kinda my point. i have no idea what the point is. why would you want to close off that section of pipe? thats what its doing basically when its in the closed position. i dunno. i think the one i have is broken anyway because compared to that photo its missing half of the component. oh and i did try to drill the old bolts out and i had no luck... most of the drill bits i have are more for wood than metal and didnt work at all. i might buy a special one for that but ultimatly i do want headers anyway i just cant afford to buy them and have them installed yet. I know if i had that much trouble with just those two bolts all the rest are going to break too so when i do get the headers i'll be paying sombody to put them on.

if your luck is like mine, those 2 bolts are just the begining.....i would assume that the door is sometype of emmisions thing, thaats all i can think of........the summit truck headers arent to much.....try running the truck and let it get nice and hot, you will probably have better luck drilling those bolts out once they are hot

I think the broken bolts have been sufficiently covered so I won't add anything there.

That part is there mainly for cold weather start and run. It helps bring the engine up to a reasonable operating temperature faster. It also preheats the fuel air mixture to aid in vaporization when the outside air is down in the freezing and the engine is cold. In spite of the hype about cold air induction improving the operation of the engine it is not an improvement when it's freezing out and the engine is cold. It requires a vacuum line input in order to function that is controlled by either a Vacuum control valve or a computer monitoring the engine temperature. That part sends hot engine gases back to the intake to help vaporize the fuel when the engine is cold.

Carbed engines use a VCV, EFI engines us a vacuum solenoid that is controlled by the EEC. If you look at the vacuum diagram under the hood, usually on the radiator support, the vacuum circuit for this is colored orange. Once the engine temperature gets up around 100 degrees the vacuum signal is cut off and the Heat Control Valve opens, (old timers call it a Heat Riser, the difference being that one is controlled by a bi-metal coil and the other is controlled by vacuum). It works in conjunction with the Intake Heat Control Valve, both are controlled by the same vacuum signal colored orange.

If you don't supply it with a vacuum signal it defaults to Open.

A typical vacuum controlled system on a carbed engine

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cool, ya learn something new every day! well sombody stripped the truck of most of the emissions stuff so the line going to the thing is missing anyway. it really only serves the perpose of a spacer between the manifold and the y pipe now. i was just curious as to why you would want to close off that section of exhaust and now i know! i'm going to try to drill those bolts tonight and see what happens i think. i bought a special bit for it. we'll see what happens.

okay my new bit that was specifically for metal and said it lasted longer and was 40% faster than all the others was a load of bs... haha it wouldnt drill that stud at all. so i decided to just bandaid the situation until i decide what to do in the long run. i wraped a piece of cable around the manifold and threaded it down one hole in the y pipe flange and back up through the other and crimped that making a loop. then stuck a screw driver in there and twisted that loop until it got reallllly tight. then i ziptied that screw driver to my oil dipstick tube so it didnt come loose. haha. not pretty but it might get us a few more trips in until i can get the headers.

ive rigged somthings in my lifetime, but not like that lol......as long as it gets the job done lol

the jurry's still out. it sounds allright in the driveway but we'll see after thrashing it on some trails haha. we're going to try to get video next time we take the trucks out. probably friday hopefully lol cant wait.

yeah that will help loosen things up a little.....you better hope that zip-tie screwdriver trick works or your gonna have a y-pipe in the mud lol

yea i've got my fingers crossed tight haha. the cable is crimped in a loop so the worst it could do is drop like an inch but thats enough to make it LOUD haha if i get 3 more trips out like it is i'll be happy.