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SeriousSAAB Running report: Vector engine build

While material was being collected and sorted for this site, we ended up with a 2002 9-5 Vector 2.3 automatic. As most readers will know, the second generation 2.3s (except the Aero) gained a useful 15 bhp over the original cars providing 185bhp, while the Aero power output went up rather more to 250bhp. We reckon that the second generation cars are satisfying to drive so couldn't resist when when this car came along. In this, the first of our running reports, we run through the process of rebuilding a SAAB B235 engine. Anoraks (we hope) will love it but for most readers, it will be a bit of an 'eye-opener'.

First impressions of our Vector were not good. The car had sat unused for some time, judging by the dull and rusty brake discs. Apparently, the car has failed on the road with loss of oil pressure and there was an ominous rattle, we were told. A new SAAB turbo charger had been fitted 18 months previously but the oil hadn't been changed nor had the sump been dropped and now, the turbo too had been damaged -to the point that it had actually seized- by catastrophic loss of oil pressure. Had we bitten off more than we could chew?

Why specialists often advise against rebuilding SAAB engines

Rebuilding ANY engine is something a lot of specialists will advise against. There are two compelling reasons for this: stripping an engine will take even an experienced technician a couple of hours and inspecting the components and then cleaning them will incur a lot of labour charges. And for what? It may well be, that the stripped engine will have damaged pistons or a crank with oval journals. The cranks can be ground (to 0.25) but shells are hard to source and the whole exercise is a complete and utter total waste of time if the engine is not SURGICALLY clean.

The engines must not be stripped or rebuilt in any sort of hurry and there are traps for the unwary that could leave your rebuilt engine a smoking wreck within a few hundred miles. For instance, if you do not remove the timing case dowels and try sliding the timing case on, not only can you damage the head gasket but also end up with NO oil pressure if you don't know what you are doing. Things like the cooling jets -fondly referred to by one veteran SAAB man as 'Benny and the Jets' (after the Elton John song...) - for the pistons (in the bottom of the cylinder block) MUST be removed and cleaned with solvent and compressed air. You also need to know that it is essential to check the oilways for the balance shaft lubrication setup from the centre main bearing. Changing the balance shaft bearings requires special SAAB service tools - and a VERY steady hand.

It takes a simply staggering amount of time to get the basic components clean enough to work on - there is absolutely NO point in fitting new shell bearings, timing chains and oil pumps within a dirty block, particularly when the number one reason for needing a rebuild in the first place was poor lubrication caused by dirty sludge. Sludge accumulates in breathers, blocks the oil pick up strainer and lurks in the oil cooler and gets trapped inside the timing case and cylinder head galleries. Cleaning the sump, block, cylinder head and timing case PROPERLY will take FAR longer than dismantling the engine itself. For most specialists, the cost of their time to the customer means a new short engine is the most cost effective solution.

John Wilcock (North East SAAB Specialists) had this to say "customers would look at me as if I had 10 heads if I proposed charging them for the amount of time you guys put into making your engines super clean. You just couldn't do it on a commercial basis."

What we did with (1) the crankshaft & cylinder block

Any engine with an ominous bottom end rattle means that the crankshaft is damaged. Very often the cranks are damaged as the result of massive overheating caused by a piston seizing in the cylinder bore due to lubrication failure. As we have stripped a number of B235 engines (the 2.0 and 2.3 cranks are different, by the way) we knew we had a spare crank from an engine that had suffered just such a piston failure. This crank had been checked for wear (plastiguage) before removal but we packed it off to Smiles Engineering (Newcastle) for further checks and polishing, if they agreed the crank was serviceable. We had another 2.3 block that was pressure washed, then chemically cleaned and honed before we cleaned the pistons, fitted new rings and checked the connecting rods. Readers should note, if considering similar operations on their own cars, that connecting rods from different engines must NOT be mixed.

What we did with (2) the cylinder head

While we awaited the return of the crankshaft, a spare cylinder head was removed from an engine and checked for damage. As part of our routine, we remove all exhaust studs -some are found to be snapped- and chucked away the thermostat. This is easy to do with the engine in the car but a breeze with the head on the bench. It is important to note that the thermostat must be fitted with the vent hole uppermost.

SAAB B205/235 cylinder heads (and indeed the related but different heads on the B204/234 engines in the 9000s) need treating with care. Using non-standard gaskets is a no-no: pattern cam box seals don't fit properly in our experience and a genuine SAAB head gasket (or Elring OE spec) is the way to go. The bolts should be changed too.

It is very important not to mix the cam shafts or followers (tappets) up (we mark them with paint) and we make sure that all bolts for the keeps go back where they came from. This isn't being obsessive so much as observant: some of the inner bolts on the camshaft keeps are machined - these provide the oil supply.

All valves were removed (using a Sealey valve spring compressor), de carbonised and cleaned while a similar operation was carried out on the cylinder head chambers and ports. Anyone who has worked on the previous 9000/900 series of cars will spot evolutionary changes in the B205/235 cylinder heads. Apart from requiring a different head gasket, the head sports valves that are very much thinner and this makes removing collets fiddly. It is essential not to mix valves and dealers' workshops have a special rack type container for this very purpose.

Grinding the valves isn't especially hard but actually cleaning the cylinder head and especially al the oil ways and galleries around the valves took far longer. In short, this isn't a job to rush if you want to do the job properly. Typically, we spend a day and a half on full cylinder head strip, clean and rebuild. This would cost a small fortune at a specialist!

What we did with (3) the timing gear

Timing gear will last around 150,000 miles PROVIDED synthetic oil has been used ONLY and it has been changed like clockwork at not more than 6 month or 6,000 mile intervals. This isn't a claim SAAB make - it is our observation, based on running well over 200 4 cylinder petrol engined SAABs. Typically, changing just the chains doesn't work and it is far too much work to do more than once, so we just bin the lot and fit the full SAAB main chain and balancer chain kit. This is much cheaper than buying al the components individually and plenty of dealers and specialists will sell you the kit at a substantial discount.

What we did with (4) the timing case & oil pump

One potential source of trouble with the B205/235 engine is the oil pressure relief valve. Unfortunately, it is an item that is seldom removed and consequently in unscrewing it, the threads in the alloy timing case often come out too, rendering the item scrap. We didn't like the look of our timing case and when the threads came out with the relief valve, a new cover was ordered (£158 inc delivery).

A set of new oil pump gears can be fitted only if the top of the pump mating face is not scored. These gears may look OK but the acid test is when the old and new are placed side by side. Very often, the difference is alarming! The oil pump seal and timing case seal need routine replacement.

What we did with (5) the sump & strainer

There is no silver bullet, magic solution for cleaning sumps. Professional engine reconditioners have dedicated washing plants but DIY owners don't have access to such facilities. We favour a 3:1 mix of paraffin & Jizer for general cleaning but while this is excellent for grime and oily deposits on engine block and cylinder head external surfaces, it is less effective at shifting sludge and varnish inside the engine. We have tried everything from commercial strength caustic soda (needs using with care on alloy parts!) to traffic film remover. Caustic soda is a good degreaser for workshop floors and in a plastic container it is great for cleaning dirty nuts bolts and fasteners but we reckon traffic film remover in a bath (a cut down 25 litre drum) is best for dunking and soaking bigger parts. Even so, there is always need for a good scrub with an old wheel brush or toothbrush.

It is our practice to re mesh the oil pick up sump strainer with 20 mesh 304 stainless steel woven wire because we have identified a problem with sludge particles blocking the 30 mesh fitted at the factory. Wider 20 mesh is less likely to block and is what SAAB used to specify before 1993. The Vector sump was washed, cleaned and the strainer was re-meshed before being fitted with a new rubber 'o' ring seal. These seals MUST be replaced because they harden and often split when the strainer is removed. It is important to note that ONLY the recommended SAAB flange sealant should be used on the sump to prevent 'bobbles' of cement ending up in the engine... which will block the strainer (the last thing anyone wants). At around £17 a tube, it isn't cheap but we find a little goes a very long way. A number of tubes have been supplied to local garages who were not impressed with the price at first but have found the stuff 'must have kit' for their workshops.

What we did with (6) the oil cooler

Oil coolers and their pipes hold an astonishing 25% of the 4 cylinder petrol engine's oil capacity or plenty of places for gunge, grime and the dreaded sludge to hide. If an engine has suffered a major failure, the cooler should be replaced. We raided our spares stash and found a suitable cooler which was left in a Safety ™ tank for an hour at one of the local garages who very kindly offered to let us use their facilities.

What we did with (7) the gearbox

Ever helpful Eazigears (Thornaby) had a look at the transmission for us while it was out of the car and ended up fitting a new torque converter seal and supplying the correct fluid. The 5 speed automatics that are fitted to second generation cars (from 2001) do not use Dexron 3 but a special grade of mineral oil (ATF3309).

What we did with (8) the oil seals

Oil seals that look OK can come back to haunt you later and at least one 9-5 power unit had to be lifted back out when it was discovered that the flywheel oil seal appeared to be leaking.

What we did with (9) the turbo charger

After dealing with these cars for some time, we know that there is more chance of being struck by lightning or seeing a unicorn prancing down the road than finding a good, serviceable used Garrett GT17 turbo charger. As we knew the turbo on the Vector's original engine was trashed, we sourced an exchange unit from Turbo Activ (Teeside). We have had turbos from Essex Turbo in the past (excellent company to deal with) but since we needed a turbo within the hour, jumped into another SAAB and headed off the 27 miles or so down the A19.

What we did with (10) the ancillaries

A golden rule is to swap ALL ancillaries from your old engine. That includes the engine wiring harness because there are untold differences between cars made even within months of each other.

We binned the water pump - Rowcliffe SAAB at Taunton in Somerset had the full pump for sale at £28 + carriage + VAT (a spectacular saving on the £108 list price) and it was here the next day.

Pulley wheels for the serpentine belt can be torture to swap when the engine is back in the car so it makes sense to check each one carefully. None of our pulley wheels were worn but we binned the serpentine belt anyway.

What happened when we fitted the engine and tried starting it up

With the complete power unit back in the car and all fluids topped up, the great moment came to start the engine up. We invariably remove the spark plugs, disable the fuel pump (remove the fuse) and unplug the Direct Ignition unit before attempting a startup on a freshly built engine. We do this because it takes what seems like an eternity to get the oil pressure up, even with the spark plugs out and if the fuel pump is running, excess fuel can damage the catalytic converter. As the oil cooler, filter, pipes and valve gear are all effectively dry, the engines always sound very noisy at first.

The oil pressure was up fairly quickly, so the plugs went back in and the ignition unit reconnected. Happily, the engine started immediately and no leaks were detected. After ten minutes running the engine was noticeably quieter, as the oil worked its way around the hydraulic lifters and the smoke from oily hands on things like exhaust manifolds subsided. All in all, a great success.

Inventory (ALL genuine SAAB unless otherwise stated)

x10 main bearing shells (std)
x8 connecting rod bearing shells (std)
x1 piston ring set (std)
machine shop charges (polishing crankshaft & honing cylinder block)
GM/SAAB flange sealant
timing case seal
new timing case cover
timing chain kit (the SAAB kit includes ALL rails, sprockets, guides and both chains*)
oil pump kit
oil pressure switch
flywheel seal
dip stick tube seal
strainer seal
20 mesh woven stainless steel sheet (to re mesh the strainer)
turbo charger + fitting kit (from Turbo-Activ)
cylinder head gasket kit
cylinder head bolt set (Scantech)
exhaust manifold stud set (Scantech)
crankcase breather fix kit (Speedparts)
serpentine belt
water pump
oil filter
thermostat

*The kit ALSO contains a good few oil seals but NOT the main chain tensioner.

 


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