I have a 1990 305 TBI camaro. I have been noticing the car hesitating and knocking a lot under acceleration so took it to the garage. Apparently the non-drivers side manifold(i think you guys on that side of the pond call it a header?) gasket has blown. i asked the garage how much it will be to do the job and he said he is not sure as he may have to remove the engine to change the gasket. Can anyone tell me if this is necessary or can it be changed with the engine in place?? He also said i need new studs and nuts and also may require a manifold (header) to exhaust gasket. I assume the gaskets are readily available but are the nuts and studs?? Any help you guys can give will be much appreciated.

 

It should be able to be done in the car, although you do need to remove the top half of the engine to do it (TBI, Intake, heads, etc). This is providing that you're using head bolts rather than studs. They came with bolts from the factory. If using studs, the drivers' side head will often not clear the brake vacuum booster, so you have to remove the booster before removing the head.

All the gaskets and head bolts should be readily available from your preferred auto retailer. You do need to remove the exhaust manifold, since it's attached to the head, which means you'll need to replace the gasket anyways. Unless the manifold is cracked, there's no reason to replace it unless you're planning on upgrading to headers which use long, individual primaries that converge into a larger collector, as opposed to a normal log style manifold. At worst, you may need to resurface the exhaust manifold sealing surface, which any machine shop can do (I've seen it done with large belt sanders before, too).

Additionally, it's best to have your heads checked over for cracks or other issues at a machine shop while they're off the car.

All in all it's not a terribly difficult job, just make sure you keep track of where all the wires, vacuum lines, and whatnot goes. Pictures are a big help here.

 

Thanks that's some useful information. The garage said I would probably need new studs so maybe he was assuming they were studs without having a good look. As far as i can tell it is factory stock so it is probably bolts like you said. If they are bolts and assuming they are not seized it should be a easier job as there should be more room to manoeuvre the manifold off I assume?

 

No in fact we don't... the cast-iron parts that the factory supplies, we call "exhaust manifolds"; a "header" is a tubular thing, usually MUCH longer, virtually always aftermarket.

There is NO REASON WHATSOVER to remove the head, let alone the engine, to change an exh man gasket. 6 bolts (maybe some of them are studs with a nut on them holding an accessory like a heat shield or something, so that makes it SO terrible, 2 nuts in addition to the 6 bolts) and you're done.

No need for new bolts or studs unless you break some.

This is not a job for "garage". I'm not even sure what that is: from all I know, it takes longer to have one of those work on your antique, than to do it yourself. By the time you factor in how much one of those things costs, there's DEFINITELY no point in using one.

In point of fact, the factory doesn't even use gaskets at all on manifolds, because they DON'T WORK. If you have manifolds and there's a gasket in there, best thing you can do is, remove the manifold ENTIRELY (OMG... 2 more nuts) and lift it up out of there, sand all the gasket schmutz off of it, file it flat with a LARGE flat mill file, sand the corresponding schmutz off of the head, and put it back together RIGHT (i.e. without a gasket). Put a bit of anti-seize on the bolt threads to make it easier for next time.

And PLEEEEZ, forget about "garage" and learn to do this sort of thing yourself.

 

No to change the exhaust manifold gaskets you do not have to remove head or engine.

It would be very dumb to even suggest removing the engine for that job. It's like an hour job at most to change that gasket out.

 

In the repair business, this is code for "I am unfamiliar with that type of car. Get it away from my shop!"

 

My apologies. I read "head gasket" for some reason.

 

I don't think from the factory stock exhaust manifolds even had gaskets