85 2.8 v6 SE
I am in the process of replacing the gasket of the rear exhaust manifold. One of the other bolts is pretty much stuck . I have tried to soak it in pb blaster , back and forth loosening , and no luck . I will keep trying but what happens when i break the top off ?
How do i drill out the old bolt . What tools , etc . How do i fit a drill in that tight spot ?
thanks

First do everything you can to get the bolt out without breaking. Carefully heat with a torch, let cool and try to turn.You are lucky it is only one stuck or broken as usually there are several. There is a GM (Kent Moore) tool for this that was designed to be used by dealers to do the manifold recalls. That's why it is not shown in the shop manual. Basically it is a jig that is bolted in place of the manifold (after manifold is removed) using at least two bolts. Each bolt position has a tube welded onto it that centers and guides a drill bit to drill out the broken bolt. It is still hard to get a drill in and usually a 90 degree air drill is needed. I have this tool and it works but it is still a frustrating time consuming experience. If I have more than two broken bolts I find it quicker and certainly better to pull the heads off and then drilling out the bolts is easy. This isn't as hard as it sounds and gives you the chance to clean up and fix any other problems while the upper manifolds etc are off.

quote Originally posted by MRBLUE87: First do everything you can to get the bolt out without breaking. Carefully heat with a torch, let cool and try to turn.You are lucky it is only one stuck or broken as usually there are several. There is a GM (Kent Moore) tool for this that was designed to be used by dealers to do the manifold recalls. That's why it is not shown in the shop manual. Basically it is a jig that is bolted in place of the manifold (after manifold is removed) using at least two bolts. Each bolt position has a tube welded onto it that centers and guides a drill bit to drill out the broken bolt. It is still hard to get a drill in and usually a 90 degree air drill is needed. I have this tool and it works but it is still a frustrating time consuming experience. If I have more than two broken bolts I find it quicker and certainly better to pull the heads off and then drilling out the bolts is easy. This isn't as hard as it sounds and gives you the chance to clean up and fix any other problems while the upper manifolds etc are off.

well .. I probably have more than 1 to deal with so i am going to plan on drilling them out and extracting . does anyone have the part number for the Kent Moore tool ? i cant seem to find it online. I am not that confident in taking the heads off with my experience so i will take my time on each one . thanks

[This message has been edited by bsculptor (edited 02-11-2008).]

make sure you use a cobalt drill bit. It will save you a lot of time drilling.

You use a cheat bar from below and slowly turn it?

Take the decklid off, it makes it alot easier to get at the studs

I used a cheat pipe on a strong ratchet after soaking for 2 weeks. Heating up the bolt is another way but, you stand the risk of fire.

If it breaks, get yourself a carbide 1/4" bit. You might want to get a 3/16's bit to drill a pilot hole though.

You then get a Heli-coil kit at your auto supply. It comes with the right size drill bit, tap, and 8mm heli coils. And yes, taking the deck off is a big help. Be thankful it is the rear bank BTW.

Arn

Dont use any type of easy-out, if it breaks you will be screwed and half the time they do break. Bit the bullet, pull thenhead and bring it to a machine shop. NAd use lots of anti-seeze when you put it the header back on.

quote Originally posted by Francis T: Dont use any type of easy-out, if it breaks you will be screwed and half the time they do break. Bit the bullet, pull thenhead and bring it to a machine shop. NAd use lots of anti-seeze when you put it the header back on.

lol - yup - happened to me. luckily - I have a buddy who is awesome at bolt extraction. yes - the only "real" way to drill it out is by having open access - which means either pull the head & do it on a bench, or remove the whole cradle.

once the head breaks off, you can remove the manifold, and maybe able to get a "cup" type extractor on it. which may end up breaking the remaining stud, or may actually get it out.

but - the real key to drilling is: be able to stay centered & stay straight with the hole. you can carefuly drill, just smaller than the threads, and then pick out the remaining bolt peices with a pick. then follow with a tap 8mm 1.25 I think it was.

Ok .. i have a total of 3 broken bolts . sounds fun right ?
anyhow . Would anyone know where i can find that GM (Kent Moore) tool for this that was designed to be used by dealers to do the manifold recalls ? model number ?
Or if i can Rent it from anyone .. i will paypal you the money for the rental + however much it is for your security .

I am going to try and extract it while still in there (mabee i am crazy for doing this but gonna give it a try ! )

FOR the home mechanic!!! who would rather be tortured by chinese nung mercenaries than remove a head!! I glue or jb weld a piece of plastic (soda bottle cap)to the head thread hole where the broken stud is.. if the stud is broken off,below the surface the flat cap has a hole at the top where you squirt or pour BP Blaster,, the cap holds the blaster in a resevoir soaking the bolt better than 100 sprays of blaster,, the broken stud is at an angle and the blaster does not so easily "move up hill" this is for the person that does not want to remove a head..If a piece of stud is sticking out you can place a bottle cap around the bolt,, force the cap against the block (the top 1/4 will be missing) so you can spray or pour pb blaster in the cap .. the fluid will drain out but the liquid will pool up temporarily to more effectively flow into the rust and corrossion.once the bolt is soaked as good as you can get it..you drill first with a small drill bit in a dremel or small rotary grinder.. the regular size drill is difficult to operate in the tight surroundings..so if you can start a hole it makes it easier to use the drill ..the broken stud is normally a very hard steel if you can pinprick the stud in the very center,with a punch your small bit will start the hole you need and the small bit is easier to control so you can stay center and at the correct angle.once you have the hole at the correct angle,then you try to drill at the correct angle with the larger drill,,use W D 40 as a lubricant,when into the bolt an inch try to reverse drill the bolt out this seldom works but when it does even the atheist pray to god ..you must be ready to reverse drill while the bolt is hot you must remove the heat shield and anything in the way,,this can only be done from the bottom.. ..3 bolts???? good luck, only use an ez out if you are positive you can get the broken bolt out... 4 bolts ??pull the head for certain actually any thing over 2 broken bolts the head should be pulled unless at least one will be easy to remove..any time you pull the head at the least,, replace the valve oil seals .. all of this is difficult to do because of close quarters and the angle of the studs.. the head is easier to clean from the bottom so you can attach the caps.. jb weld works best and is easier to remove than the head..Remember every fiero owner is not a motorhead with a shop full of tools and a desire to become mechanic of the year..use top quality drill bits you can make a guide from plastic use the manifold as a template...or jam a tight dowel in the exhaust manifold flange hole...drill a hole dead center voila! ""special centering tool"" some have trouble reading my post hope you understand 75% of this ..

[This message has been edited by uhlanstan (edited 02-12-2008).]

OR if you have a welder you could weld a bolt onto the broken stud. The heat from welding helps to loosen the stud and you have a nice fresh bolt head for you socket or wrench to turn. Only works if the stud is broken off above the surface of the head.

quote Originally posted by bsculptor: Ok .. i have a total of 3 broken bolts . sounds fun right ? anyhow . Would anyone know where i can find that GM (Kent Moore) tool for this that was designed to be used by dealers to do the manifold recalls ? model number ? Or if i can Rent it from anyone .. i will paypal you the money for the rental + however much it is for your security . I am going to try and extract it while still in there (mabee i am crazy for doing this but gonna give it a try ! )

all I can say is: good luck. my 1 broken bolt was tough enough, and my cradle is out. I cant imagine trying to do 3 in car. but, I also had a broken EZ-Out to deal with. I understand not wanting to do the valve lash - which is the worst part of removing the head. gives ya a fine chance to do some port work also

If you are not an experienced gearhead do everything to avoid head removal ..I understand how daunting this can appear if you have never done it before....the gearheads on the forum concider this as a walk in the park (almost) with the help of a service manual and the forum it is possible..If you have a selection of boxes available as you disasemble you can keep the various parts in some order,and this helps with reasembly..take notes!! the most difficult fiero job is transmission removal out the side,, next engine removal ..If you write down the sequence of disasembly on a piece of paper you can have this beside you as you work if you need to remember something not listed write it down on the paper ..now the bad news do the rear head also replace valve seals any time you remove a head on an older engine, you should reseat the valves lightly also. never use a drill to spin reseat valves NEVER ,never. Unless you do not care about engine perfromance or reliability

quote Originally posted by uhlanstan: If you are not an experienced gearhead do everything to avoid head removal ..I understand how daunting this can appear if you have never done it before....the gearheads on the forum concider this as a walk in the park (almost) with the help of a service manual and the forum it is possible..If you have a selection of boxes available as you disasemble you can keep the various parts in some order,and this helps with reasembly..take notes!! the most difficult fiero job is transmission removal out the side,, next engine removal ..If you write down the sequence of disasembly on a piece of paper you can have this beside you as you work if you need to remember something not listed write it down on the paper ..now the bad news do the rear head also replace valve seals any time you remove a head on an older engine, you should reseat the valves lightly also. never use a drill to spin reseat valves NEVER ,never. Unless you do not care about engine perfromance or reliability

yes - true. but, I do beleive that bolt extraction of this nature is actually a more skilled job than doing a head gasket - and doing it in such a tight space takes more skills than I got. I suppose it comes down to where your skills lie.

but - yes - if unsure - notes, pics, manuals - and of course - us here on the forum.

It is a whole lot easier to remove the head to replace manifold bolts. However, removing the head on the stock Fiero intake is a PITA also, and you are into the expense of new gaskets. There are right angle drive drills out there, and that might be a good investment. I agree with all the guys saying an Easyout won't work.

Arn

Agree, it is a lot of work, and a lot of things that has to be removed to get the heads out. I recently did this. However, if you are interested in mechanical work it is at the same time rather fun :-)

While the heads are out, at least take the time to remove the exhaust manifold restrictions also. Everyone says that it renders a better breathing engine and I think they are right when looking at the terrible design.

[This message has been edited by kjelle69 (edited 02-12-2008).]

Had to do the same thing a couple of weeks ago - just on however. I did have a head gasket set on hand, and was figuring that I would have to use it. I wound up heating the stud to red hot, and letting it cool a couple of times. I couldn't get a good grip with a stud remover, vise grips wouldn't touch it. I wound up drilling a 8mm hole in a piece of round stock, milling a hex on the top of it, drilling a radial 5.8" hole across the face, just breaking the face, and intersecting one side of the axial 8mm hole. Took some drill rod, cut a wedge across one end, used a file to quickly put "Teeth" on the wedge face. Placed it over the stud, stuck the wedge in, the torque of turning it pulled the wedge in tighter, and the broken stud came out. Figured I got real lucky - but it took that to get it out, I had the resources, and was still prepared to pull the head.

Good luck

Well i took it to the shop , cost me 350 plus parts ( $70 ) $420 in all . They took the head off and took it to the machine shop . New exhaust manifold gasket and head gasket . So i just got it back today .
It fixed my hesitation problem too ! so i am excited about that .
thanks all