Igot a 91 s-10 blazer 4.3 4wd with a new engine i put in 2 years ago with a very bad exhaust leak. Never had the tick before i did a powerbrake burn out the other day it is definatley coming from the driverside.I got a couple of questions i didnt put a donut gasket on the y pipes does it need one? Also can i take the manifolds off with the engine in the car with relative ease and is there a way to tell where it is leaking at before i take them out?
im gonna change the trans fluid and im gonna drop the y pipe and do the manifolds at the same time if i have to. Also i did tighten up the manifold bolts they were a little loose but no ticking or leak before the burnout.

 

ditto that, I hear an exhaust leak too on my 2.8L POS, but not sure exactly where it is coming from, how can I find it? Also I have one broken bolt head on each side, one on the driver's side, and one on the passenger's side. Does having a broken bolt mean that you have an exhaust leak, or is that a crazy assumption? Also is it better to attempt to remove the exhaust manifold bolts while the engine is warm/hot or when it is cold? Be gentle I am not a mechanic nor do I play one on TV, LOL... and thanks in advance

 

If either of you have an old doctor's stethoscope, you can use this to determine where a leak is by removing the large metal end and tracing the tube alone the connections in the exhaust. If you hear the exhaust pulse, you have found the leak.

 

So I took on the exhaust leak repair. I had one broken manifold bolt on the driver's side, but I knew if I removed the exhaust manifold it would stick out so I could use some vice grips and unscrew it. Well as I began unbolting the other 5 bolts I realized that another bolt had to be broken already as well but kinda hanging in there. So that's two broken bolts out of 6. Then I broke both of the flange bolts because there was no way in hell to get them to budge. These are the kind of bolts that are thick as your index finger for about 3 inches and then get as skinny as your pinky where the threads are at for about an inch at the end. No wonder tons of replacements are hanging on the walls of your favorite auto parts store, LOL..

I used my favorite cheater pipe to get more leverage on the wrench and snap snap they went. Then I pulled off the manifold and using vice grips snaped the stud that was sticking out, so now I have to drill two bolts out of the engine block and two more out of the exhaust manifold. But wait there's more. I noticed there was no manifold gasket, could that have been the cause of the exhaust leak. Is the gasket mandatory. Remember I'm not a mechanic nor do I play one on TV.

here's a link to my pathetic Blazer webpage http://home.comcast.net/~gregski/blazer.htm there is a laundry list of Repairs, and Outstanding Problems (to make all of you feel that much better).

I will try to upload some pictures of this repair.

 

I would imagine that an exhaust manifold gasket IS mandatory.

 

This has got to be the hardest repair, not as in difficult but as in tough. It all started out becuase I wanted to remove a broken exhaust manifold bolt which I believed was the cause of my exhaust leak. Well since then I broke a second exhaust manifold bolt, and two exhaust flange bolts, a bunch of drill bits trying to drill them out, and even some easy out bits deisgned to take out broken bolts, LOL.

The guy at Kragen said that the exhaust manifold bolts are Grade 5 so they should be easier to drill then the exhaust flange bolts which are Grade 8. Well these are Metric bolts so they don't fall into the American Grade standards directly, but the exhaust manifold bolts say 10.9 on them which have stats that compare to the Grade 8, the exhaust flange bolts say 9.8 on them so that's closer to Grade 7, so the guys got them backwards sort of, LOL.

http://www.k-tbolt.com/bolt_chart.html

Just when I was getting the hang of the Grade scale, my Canadian made American Chevy has to have mostly metric bolts on it, go figure!

Question: Why don't they make the exhaust manifold and the engine block be one and the same, made in a single mold? I mean that would eliminate the gap between the two pieces of metal where most exhaust leaks happen. It would also eliminate these insane repairs and drilling 6 maybe on some vehicles even more exhaust manifold bolts.

Some pics for ya

 

The factory manifolds may not have had a gasket. Machining processes/tolerances as they were allowed for this. Combining the heads and exhaust manifolds would make for one very large and application specific part. The different exhaust manifolds required for different vehicles would turn into different heads, increasing the cost and complexity of the part and limiting interchange-ability.

I feel your pain on this project. I helped my cousin out with his Neon which had 3 of 8 (I think) bolts snapped off in the ALUMINUM head. Two of the bolts we were able to get vise grips on and turn out. The last one had to be drilled. Let me tell you, that was not fun! 5" worth of clearance from the firewall to the head and no direct line of sight. A 90* drill adapter, magnetic mechanics mirror, and some patience and we were able to get the easy out into it and screw it out without damaging the head.

 

So I was able to drill a hole in one of the exhaust flange bolts and using a special drill bit called an Easy Out, vice grips, and some gentle persuasion I was able to unscrew it. The other one I had to drill out completeley by stepping up to a bigger and bigger drill bit until I had a hole big enough to use a tapping set to re-thread the hole. Here are some more pics of this pain in the butt, very time consuming "repair".

In related news, Kragen believe it or not has a "Limited Lifetime" warranty on their made in China tools, such as the Team Mechanix 6 piece Metric Tap Set for $7.99 and the Powerbuilt 6 piece Easy Out set for $9.99, in case you didn't already know that, I took advantage of this and exchanged both of my broken sets for new ones, no questions asked.

 

Glad you got it taken care of!

 

Things were going so well, I repaired the 3 bolts I broke trying to fix the original broken one. I was back to square one, all I had to do was drill the original broken bolt out and I was home free. This being the driver side front bottom exhaust manifold bolt. Well this is when disaster struck. I was drilling away and all of a sudden a green straw was pointing at me. I was like what the hell is that, well it turns out it was a purdy stream of antifreeze. That's about the time my four year old daughter came into the garage and blurred out "Daddy the monster is going pee pee?" What can you do at a time like this your anger turns to laughter in an instance, kids say the darnest things.

So I drained all the antifreeze out using the worlds most conspiquous drain plug ever placed on a radiator on the planet. Then I stuck an Easy Out bit into the hole in the bolt and I... broke the damn thing... so now I have a hardened steel Easy Out bit stuck in a broken bolt. That seemed to plug up the hole though, so pissed off I put the exhaust gasket and the exhaust manifold back on and tightened the remaining 5 out of 6 exhaust manifold bolts. I also put in a new donut exhaust flange gasket, (this one was out of lead, the old one was out of porcelin).

Truck seems to run "ok", I hate to say "good" and jinx the damn thing, but I just don't feel good inside about the repair and wonder if it's only a matter of time before she starts leaking.

So gentlemen please tell me I am not royaly bamboozled and there is a way out of this mess.