EXHAUST MANIFOLD & GASKET REPLACEMENT (4 CYL)

Replacing Saab Exhaust Manifold Gaskets

A special thanks to Helga and Dmitry Platonoff for the contribution of this material and some other materials listed on the our faqs pages. It is Saab enthusiasts like Dmitry that makes it easier for the DYI guys that frequent the internet. Excellent Job!!!!

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Exhaust manifold removal and re-installation on the 1996 Saab 900 (4 cylinder turbo). On this example, the manifold had to come off because there were two broken studs on the driver side of the manifold. The gasket needed a replacement too

Tools Needed

13 mm socket: manifold, turbo and steering pump nuts;
two 13 mm wrenches: manifold, turbo and steering pump nuts;
10 mm socket: air filter housing;
7 mm socket: hose clamps;
Torx T27 socket: PCV line;
ratchet handle;
torque wrench;
long 1/2" socket extension;
4 mm Allen key;
drill with cobalt bits and right angle attachment;
a piece of metal pipe or a hose coupler that fits the stud holes;
small mirror;
screw extractors;
tap wrench (optionally with a 8x1.25 mm tap);
car jacks and stands or ramps.

Manifold

I had a misfortune of having a couple of studs go on the exhaust manifold. One day they just disappeared, leaving two gaping holes in the manifold. The studs were broken flush with the head.

Broken Studs

A close-up of the problem area. In my case it was not enough to just drill the studs out, because the gasket moved and was partially blocking the port (and causing a leak too). Therefore the entire manifold had to come off.

Intake

The first step is to remove the intake. The air box cover comes off with the intake pipe and the return line from the bypass valve. Plug the turbo inlet pipe immediately, YOU DON'T want any dirt to get in there.

Belt

Loosen the belt with a long 1/2" socket extension and lock the tensioner with a thin Allen key. Remove the belt from the steering pump pulley. This picture shows the air box still in place, but it's actually better to remove it before starting on the pump. The air box is secured by three 10 mm nuts.

Steering pump

The steering pump bracket is attached to the head with two bolts on the top and one under the pulley (use a 13 mm socket or wrench here). The lower bolt is a bit of a pain to get to. Unbolting the metal PCV vent pipe from the valve cover gives you some extra room.

Turbo studs

The manifold to the turbo nuts are next (13 mm). You can see that all nuts have been generously sprayed with rust solvent last night. That helped!

Manifold studs

The nuts on the remaining manifold studs come next. The three studs in the middle are short, while the outer ones are long and have cylindrical spacers on them, designed to help with deformations occurring at high temperatures.

Nuts removed

The leftmost nut took the stud with it, but the rest came off without a fight. The WIS calls for complete turbo removal, otherwise there's not enough room to get the manifold off the studs on both sides. We chose to remove the manifold studs instead, since we planned to replace them anyway.

Turbo stay

An extra wiggle room is still required to remove the manifold. It can achieved by unbolting the down pipe from the turbo, and the turbo stay from the engine block.

Hose coupler

This brass hose coupler was found at the local hardware store. It was a snug fit to the manifold and worked well as a guide for the drill bit, helping to ensure that we start drilling at the centre of the stud. A small mirror came in handy to peek into the hole to observe the results.

Drill

A right angle drill extension is needed since there is not enough room to fit the drill in front of the head. I initially purchased a set of left handed HSS drill bits, but they didn't last long enough as the studs are too hard for them. This set of cobalt bits was much better suited for the job.

ud removal

The remaining manifold studs were removed using an old trick with two nuts tightened together. The short stud closest to the two previously broken ones also broke after we attempted to remove it. Fortunately, it left a piece long enough so we could grab it with vice grips and unscrew the stud later when the manifold was off.

Manifold

Here's the manifold off the car. You can see than its mating surfaces and the gasket are still clean where the nuts were tight, but the fourth cylinder area is covered with soot on both sides.

I.N.P.

My father happened to be visiting from overseas and didn't mind getting his hands dirty. He helped a great deal and made the job much easier than it would have been if I did it alone. Thanks, dad! ;)

First Stud Removed

With the manifold off, it was easy to drill the holes deeper. Then, after some struggle with a screw extractor, the first stud came out.

Second Stud Removed

And then the other one.

Extractor Results

Here's the remaining part of the broken stud as it came out of the head.

Hole Driilled in a Stud

This is a close-up of the hole we drilled in one of the studs.

New parts

About $60 worth of parts: new gaskets, studs, nuts and washers. The big gasket installs with its metal side to the manifold, and the soft side to the head.

Turbo gasket

Time to clean the metal shavings and dirt, and pull the rug out of the turbo housing. The gasket goes on.

New studs

The manifold slides onto the turbo side studs first, and then new studs can be screwed into the head. Some were easy to put in, some required the two nut trick again.

Installing the Nuts on the Studs

After all the studs are in, start putting the nuts on. Do not tighten them yet, just put the nuts on both the head and the turbo side. Tighten the turbo stay on the engine block.

Tightening the Nuts

Tighten the nuts on the manifold and the turbo to 16 ft-lbs. Connect the down pipe to the turbo.

Re-installing the Steering pump

The steering pump bolts are hard to reach, especially the bolt below. There's only enough room to turn the wrench 1/12 of a turn.

Re-installing the Belt

Put the belt on and attach the vent pipe to the valve cover.

Last Step and we are Done

Install the air box and enjoy the job well done.

Copyright 2000-2005 Helga and Dmitry Platonoff Used with permission