When my 1991 Saab 900 turbo needed a replacement engine and transmission, I was lucky enough to secure low mileage replacements. Although I saw no need to fully rebuild them, I wondered what I should replace while I was in there. I asked everyone I could – from my independent mechanic to Facebook friends to forum members, and the folks at eEuro that have done this once or twice themselves. Here was the list of what I ended up replacing. Almost all of these minor repairs took minimal time and left me much more confident that my engine would last another 25 years.

Head:

1. Head gasket
2. Valve cover gasket
3. Planed head (professionally done by a machine shop)
4. Distributor oil seal
5. PCV bushing
6. Lubed cam carriers
7. Thermostat & seal

1. Intake manifold gasket (optional)
2. Exhaust manifold gasket (optional)
3. Exhaust manifold studs (optional) – Check out this post for tips on replacing exhaust manifold studs

Block:

1. Water pump

2. Rear crank seal (behind flywheel)

7. Front crank seal (behind crank pulley)

7. Alternator mount bushings

7. Drive belts
8. Turbo oil return pipe seal
9. Resurfaced flywheel (professionally done by a machine shop)

Transmission

5. Transmission gasket (oil pan gasket)
6. Transmission dipstick o-ring
7. Clutch input shaft seal
8. Shifter coupling

5. Shifter shaft seal

6. Inspection plate seals (if opened)

7. Pilot bearing (at center of flywheel)

8. Release bearing (on the clutch slave cylinder)
9. Swap in type 7 primaries (optional – there were different primary drives for different engines. My replacement transmission came from a non-turbo, which had a higher-revving gear ratio than a turbo. So I swapped in the type-7 primary drive from the turbo into the non-turbo transmission)

Body

1. Upper control arm bushings (the drivers side on a Saab c900 is pretty much impossible without engine removal, so now is a good time to replace them. They have to be pressed in)

2. Engine mounts (the drivers side mount is impossible without engine removal, and all three were broken anyway)

2. Upper radiator hoses
3. Thermofan switch
4. Turbo to lower radiator hose metal coolant pipe (water-cooled turbos only)

 

This process was not a full tear-down engine or transmission rebuild. My goal was to take advantage of the good condition of the low mileage parts, but replace everything that was relatively easy and affordable, or otherwise too hard with the engine in the car, and then get back on the road quickly.

Many suggested disassembling the entire block to have it professionally cleaned and painted, cylinders ported and polished, valves lapped, etc. but I opted to only vacuum out all of the oil and coolant lines and cleaned the outside as best I could. I did remove the majority of accessories and removable parts and had those professionally cleaned, or cleaned them myself with a wire wheel – this saved a lot of money and made installation much easier while visually the engine ended up much more appealing. Overall, the process was quick and inexpensive, and I would recommend it even if you have minimal experience with an engine swap. It’s possibly the quickest, easiest option to get your daily driver back on the road!

Check the eEuroparts blog next week for Part 4: Mating the Transmission to the Engine.