Exhaust manifold questions

[jeremywitt]

My driver's side exhaust manifold is loose (rear 4 bolts nearer to firewall) due to the heads of some bolts popping off. I believe this is due to vibration but in any case I would like to fix it, but before I get to work on it I wanted to ask for some advice.

I bought a Chilton manual for my truck yesterday and looked over the section about exhaust manifolds several times now, and I have some questions regarding the procedure/parts. The second step says:

2. Block the rear wheels, set parking brake, raise the front of the vehicle and support it securely on jackstands. Working below the vehicle, disconnect the electrical connectors from the oxygen senors. Unbolt the front Y-pipe from both manifolds, then detach the Y-pipe from the exhaust system.
NOTE:It will be necessary to detach the center exhaust system mount from the transmission and loosen the exhaust pipe clamp to accomplish this task.

How difficult is this procedure? Does the pipe itself have to be moved or removed before the manifold will come out? Is there a gasket that goes between the manifold and Y-pipe that would have to be replaced?

Also, step 4:

4. Lower the vehicle. Working in the engine compartment, remove the air intake duct and the throttle body resonator.

What is the resonator? I know what the throttle body is and there is another section in the book telling how to remove it but it says nothing of a resonator. I'm just guessing they are the same thing...? Also in that section about removing the throttle body it states that there is a gasket between it and the intake manifold. Would this have to be replaced as well?

The rest of the procedure seems fairly simple... so on to the bigger problem. Since the heads of those bolts are broken, what would be the best way to remove them from the manifold? I was thinking to borrow a dremel tool and grind down two sides of the stud and use a wrench to turn them... is this feasible or practical?

Also this brings up the question of if I should even go through this whole procedure of removing the Y-pipe, duct and throttle body resonator... or attempt to remove the broken bolts without doing all this and just replace them with new ones and re-tighten? This would be prefered because I think it would shorten the work time by hours probably...

Another question that is posed from that... (LoL, sorry but there's lots of questions) the manifold has been loose for about 2-3 months, I'm assuming there could be some kind of buildup between the loose parts, does this need to be cleaned before re-tightening? I guess that would entail removing all the other parts too.

Thanks in advance for reading this LONG post and for any advice presented.
JBiggs

[angus10]

You don't have to remove the Throttle Body! So don't worry about that gasket. And you want to remove air intake duct just to give you room to work, the resonater is pretty much part of it. And as far as the pipes go, you just need to unbolt them from the exhaust manifold .They don't need to be completelty removed. And as far as how hard it is , is all depends on how badly the bolts/nuts are seized in the ex. manifold and head. I would spray them with Cyclo Penetrating oil or PB Blaster for a few days before I did the job. You don't want one of those breaking in the head.

[jeremywitt]

So, I have some PB penetrating on hand, should I just start a couple days before working on it by spraying once a day on the bolts? Can it get into the engine and cause damage?

So do you think i should use a dremel and grind the sides of the remaining stud and turn it or what? I don't really have access to a welder or i would just weld a nut on the end and turn it...

Also if the if the first question is true, where can I get the bolts to replace the ones that broke? Napa, Schucks, or where...??

[wafrederick]

Remove the exhaust manifold and cut the flange bolts which are convential 3/8" coarse bolts you can get any hardware or parts store,2 1/2 to 3 inches long.Try pounding on differant size 6 point sockets,SAE and Metric.I do this once in a while and it works,a 12mm on a rusted,rounded off 1/2" for example.Grip tite make special sockets you can use on rounded off fastners and your nearest sears sell them.Clean up the exhaust manifold gasket area very good including the cylinder head where the exhaust manifold bolts to and reinstall with no gasket.I seen this work with no leaks so far

[The_Mechanic_33]

Also helps alot to remove the inner fender well.

[jeremywitt]

Thanks for responding to my questions...

What do you mean by cut the flange bolts? Cut them where?

I thought the bolts were special because they have another stud coming off the other side to bolt the heat shield to?

Also I'm not sure I understand what the socket for a rounded off fastner would do on a stud with no head?

[The_Mechanic_33]

cut or grind heads off then slide manifold off then carefully remove remaining studs. Clean gasket surface and chase holes with a 3/8 th's by 16 tap. U can purchase bolts with heat shield studs at dealer or if ya can save 2 per side and they look good reuse them and replace others. Maby weld a little stud to new bolt head for heat shield. heating the old bolt heads to a cherry red and smaller 12 point or six point sockets pounded on hot bolt head or vice gripes has worked for me also.

[wafrederick]

I mean where the Y pipe bolts up to the manifold.Chrysler is the only one that use bolts for flange bolts