E34 5 series questions....
Discussion
Hi all.
I'm considering changing my car very soon, and I'm seriously looking at picking up an E34 5 series. It'll probably be a 525, although I'm seriously tempted by a 1996 530i V8 I've spotted.
Just looking for general advice on what to look for in one of these, any models I should avoid etc.
Or should I just get an E36 325 and be done with it?
I'm considering changing my car very soon, and I'm seriously looking at picking up an E34 5 series. It'll probably be a 525, although I'm seriously tempted by a 1996 530i V8 I've spotted.
Just looking for general advice on what to look for in one of these, any models I should avoid etc.
Or should I just get an E36 325 and be done with it?
Avoid the 530i V8 for a start, 525i drives better, and is more economical, V8's are also suffer from the Nicasil problem wheres as E34 6 cylinders do not
If you really fancy a V8 go for the 540i
What goes wrong? Not a lot! Probably the best made/reliable BMW ever produced, dash displays can give problems (solved one of ours for £25 though!) and rear axle bushes a prone to wear (pretty easily fixed)
Buy a properly maintained example with a sensible mileage and good service history and you wont go wrong (personally feel its best to stick with manuals as this reduces the potential for grief)
Father has run a 518i 95 M(not as slow as you think) currently on 100k miles (owned for last 7yrs... hes just put a battery on it! lol)
Recent acquired a 520i 24v 94 M with 73k miles on it in mint condition and FSH, paid £800, now fully serviced, MOT'd and taxed and still only owes £1200!
Both scrub up like new
Cant think of anything better for the money!
>> Edited by mustard on Wednesday 29th March 20:48
If you really fancy a V8 go for the 540i
What goes wrong? Not a lot! Probably the best made/reliable BMW ever produced, dash displays can give problems (solved one of ours for £25 though!) and rear axle bushes a prone to wear (pretty easily fixed)
Buy a properly maintained example with a sensible mileage and good service history and you wont go wrong (personally feel its best to stick with manuals as this reduces the potential for grief)
Father has run a 518i 95 M(not as slow as you think) currently on 100k miles (owned for last 7yrs... hes just put a battery on it! lol)
Recent acquired a 520i 24v 94 M with 73k miles on it in mint condition and FSH, paid £800, now fully serviced, MOT'd and taxed and still only owes £1200!
Both scrub up like new
Cant think of anything better for the money!
>> Edited by mustard on Wednesday 29th March 20:48
mustard said:
Avoid the 530i V8 for a start, 525i drives better, and is more economical, V8's are also suffer from the Nicasil problem wheres as E34 6 cylinders do not
Hmmmm did wonder about that on the V8. Althought would it be alright if the engine had been replaced under warranty in the past? Was planning to get a manual if I got a 525 anyhow.
What exactly is the Nicasil problem???? Have heard the term a lot, and know it's something to do with the cylinder linings or something, but not a lot else. Please enlighten me!
Hi
I run a e34 535i, cracking cars, so well built.
I believe the nikasil issues can be checked by a compression check on the engine. if it sfine no worries. They seem to survive if they are given proper long trips as lots of short trips will hurt them.
Anyway the straight sixes sound better and seem to go on forever.
Feel free to tell me i am wrong.
Love the performance of mine, seems effortless, plus it drifts quiet well
Paddy
I run a e34 535i, cracking cars, so well built.
I believe the nikasil issues can be checked by a compression check on the engine. if it sfine no worries. They seem to survive if they are given proper long trips as lots of short trips will hurt them.
Anyway the straight sixes sound better and seem to go on forever.
Feel free to tell me i am wrong.
Love the performance of mine, seems effortless, plus it drifts quiet well
Paddy
apache said:
540i is well rapid but returns about 19 mpg
My 540i Touring auto averages 23 and can top 30 on a motorway run.
Nicasil is the chemical lining of the alloy cylinder bores. BMW used it in bike engines for years and started using it for cars in the 1990s, as did others including Jaguar. There were some problems with the lining wearing due to the action of sulphur in fuel, and later BMW engines used a different lining system, Alusil. Later still the engine was reworked with separate steel liners.
Anything's possible, of course, but I would expect that any engines likely to suffer Nicasil troubles would have done so by now.
A less well know fault is that the oil pump bolts loosen over time, and eventually the oil pump drops off the engine. If you buy one the first job should be to drop the sump and tighten the bolts.
Well I've owned all 3 E34 variants mentioned here, 525i, 535i, and 540i, so here are my opinions.
525i-mines a '95 525i 24v touring. Great car, light up front so nimble handling. 35 mpg on long summer motorway cruise & 17.6 gallon tank = 600 mile range-who needs a Diesel? Watch out for the dreaded plastic impeller water pumps on the small sixes-fail without warning from inside. Pump appears to be turning ok from outside when engine watched, but engine overheats for no apparent reason, and heaters blow cold air only. Fit later model metal impeller pump. Other than that great cars although you have to rev the small sixes to shift the large E34 bulk, particularly the 520i 12v. 24v Vanos cars best.
535i-great cheap old torquey bruiser, especially fully loaded SE model with all the toys etc. Unburstable engine but check camshaft oil spray bar bolts are tight-they work loose over time & starve cam of oil, giving cam clatter which is a huge cylinder head off job to fix. Handling still good and will give genuine 30mpg on long motorway cruise.
540i-only good if you can get an Alusil-engined one, or a healthy Nikasil one. Fabulous when running properly and really makes the car. Remove the restricter pipe from the front of the airbox intake for bit more top-end BHP and more rorty intake noise from growly V8. MPG varies from comical around town with a cold engine to very good on a long motorway cruise. Mostly does 22mpg but drops to 18mpg or less round town on a cold day, and will really give 28-30 genuine mpg on long run on summers day. Nature of engine means you'll want to drive it everywhere with the loud pedal welded to the floor
E34's are mostly unburstable and one of the best built modern BM's. They are heavy cars though so don't get a small-engined one cos you'll constantly have to cane the engine to make progress. Fuel consumption around town not brilliant on any model cos they're heavy old brutes, so might as well get bigger-engined versions-at least you'll have the power and can forgive fuel-guzzling!
Best all rounder? 525i 24v Vanos '93-'96. Best cheap old bruiser-535i SE with leather & air-con + all the toys-get yours for £1500 or less.
Finally, what about the 518i? OK if you know what to expect, as in not a rocketship, but very light in the nose so good handling. 1.8 four-pot more torquey lower down than 2 litre 12v six-pot so not as bad as you'd think. Huge fuel tank and 35+ mpg on motorway gives Diesel-like range.
Avoid metric tyres and stick to bog-standard cheapo 15 inch wheels. Look tiny compared to todays 18 & 19 inchers but you'll be laughing all the way to the bank cos tyres won't break the bank.
All in all one of BMW's best ever car ranges. I've still got my '93 540i (with Alusil engine courtesy of previous owner & BMW warranty) and '95 525i 24v Vanos touring, and I'll never sell them cos they're both great machines
Happy hunting!
525i-mines a '95 525i 24v touring. Great car, light up front so nimble handling. 35 mpg on long summer motorway cruise & 17.6 gallon tank = 600 mile range-who needs a Diesel? Watch out for the dreaded plastic impeller water pumps on the small sixes-fail without warning from inside. Pump appears to be turning ok from outside when engine watched, but engine overheats for no apparent reason, and heaters blow cold air only. Fit later model metal impeller pump. Other than that great cars although you have to rev the small sixes to shift the large E34 bulk, particularly the 520i 12v. 24v Vanos cars best.
535i-great cheap old torquey bruiser, especially fully loaded SE model with all the toys etc. Unburstable engine but check camshaft oil spray bar bolts are tight-they work loose over time & starve cam of oil, giving cam clatter which is a huge cylinder head off job to fix. Handling still good and will give genuine 30mpg on long motorway cruise.
540i-only good if you can get an Alusil-engined one, or a healthy Nikasil one. Fabulous when running properly and really makes the car. Remove the restricter pipe from the front of the airbox intake for bit more top-end BHP and more rorty intake noise from growly V8. MPG varies from comical around town with a cold engine to very good on a long motorway cruise. Mostly does 22mpg but drops to 18mpg or less round town on a cold day, and will really give 28-30 genuine mpg on long run on summers day. Nature of engine means you'll want to drive it everywhere with the loud pedal welded to the floor
E34's are mostly unburstable and one of the best built modern BM's. They are heavy cars though so don't get a small-engined one cos you'll constantly have to cane the engine to make progress. Fuel consumption around town not brilliant on any model cos they're heavy old brutes, so might as well get bigger-engined versions-at least you'll have the power and can forgive fuel-guzzling!
Best all rounder? 525i 24v Vanos '93-'96. Best cheap old bruiser-535i SE with leather & air-con + all the toys-get yours for £1500 or less.
Finally, what about the 518i? OK if you know what to expect, as in not a rocketship, but very light in the nose so good handling. 1.8 four-pot more torquey lower down than 2 litre 12v six-pot so not as bad as you'd think. Huge fuel tank and 35+ mpg on motorway gives Diesel-like range.
Avoid metric tyres and stick to bog-standard cheapo 15 inch wheels. Look tiny compared to todays 18 & 19 inchers but you'll be laughing all the way to the bank cos tyres won't break the bank.
All in all one of BMW's best ever car ranges. I've still got my '93 540i (with Alusil engine courtesy of previous owner & BMW warranty) and '95 525i 24v Vanos touring, and I'll never sell them cos they're both great machines
Happy hunting!
Agree with RedOctober...
My wife has been driving a 1995 E34 525i Auto Touring daily now for well over four years. She put on nearly 50,000 miles lugging our three kids plus others on the school run...it' done countless long runs...trips to the dump etc. Sure there's the odd nick, dink, stone-chips etc. But this thing has taken every abuse that has been thrown at it!I spent most of all day yesterday cleaning the thing up for her... I almost half wish the thing would break as an excuse to get something else...but it doesn't seem inclined to play ball! Hers now has just under 130K miles...others have many more miles...
I have a total of five BMWs to choose from...I'm taking my two sons and a friend camping to the Le Mans 24-Hour this June...My choice of car for the trip? You guessed it...E34 525i Touring!
In terms of wheels...if the car has 'metrics' on...don't worry! 16" from an E38 7-Series are a direct bolt on; 16" from an E39 5-Series will work too with a spigot ring (I think that's the right way round?...It's late and I can't be sure of the top of my head).
Still a handsome looking car!
www.bmwclassics.co.uk/
My wife has been driving a 1995 E34 525i Auto Touring daily now for well over four years. She put on nearly 50,000 miles lugging our three kids plus others on the school run...it' done countless long runs...trips to the dump etc. Sure there's the odd nick, dink, stone-chips etc. But this thing has taken every abuse that has been thrown at it!I spent most of all day yesterday cleaning the thing up for her... I almost half wish the thing would break as an excuse to get something else...but it doesn't seem inclined to play ball! Hers now has just under 130K miles...others have many more miles...
I have a total of five BMWs to choose from...I'm taking my two sons and a friend camping to the Le Mans 24-Hour this June...My choice of car for the trip? You guessed it...E34 525i Touring!
In terms of wheels...if the car has 'metrics' on...don't worry! 16" from an E38 7-Series are a direct bolt on; 16" from an E39 5-Series will work too with a spigot ring (I think that's the right way round?...It's late and I can't be sure of the top of my head).
Still a handsome looking car!
www.bmwclassics.co.uk/
If you look at an auto do make sure it's shifting OK and there's no delay or big thump into reverse: valve bodies can need rebuilding when the plastic balls in the one or two of the valves internally wear and pop through holes they shouldn't. Water pumps already mentioned, also worth checking the radiator hose joints out as they're pastic and can go brittle and disintegrate.
Front suspension thrust arms and associated bushes wear and cause steering wobble, rear subframe mounts give up the ghost (self-steering rear end) and anti roll bar links ('dogbones') also go. All of these things are to be expected at 100k and higher.
If you're feeling flush, the Switchlogic mod (from Birds in Uxbridge) gives switch mode autos a semi-automatic paddle-shifty thing, which is a fairly nice compromise when you want to push on a bit *and* make the gearchange decisions.
Other stuff: electric seats can develop problems, usually to do with the cables (and their sheathes) that run from the motors to the gearing expanding/contracting with age. Weak batteries can cause bizarre issues, despite everything else seeming to be OK. On the V8s, rocker cover gaskets get weepy, allowing oil into the wells where the coils & plugs live, leading to misfires due to bad contacts. Steam cleaning to be avoided for same reason if possible. (Note to my local garage, grrr...)
Examine the bottom of the doors closely - around plastic strip along the bottom. The drain holes can block and the bottom edges can rot from the inside, hidden by the plastic strip. Despite that, I've been told the body is galvanised (or at least well rust-proofed) and shouldn't rust unless badly fixed/sprayed.
Errr, bit of a random brain dump that. You're unlikely to find all these things on one car, but they're all things that crop across a cross-section of high miles E34s. I've had most of 'em, but my car has been to the moon and back.
Lots of good info on www.bmwe34.net and www.bimmer.info.
Lastly, my personal opinion is that the V8s sound fabulous. It's just a shame the exhausts aren't a touch more vocal.
--Chris (E34 540i, 163k miles, mixed 20mpg - and I don't drive like a nun!)
Front suspension thrust arms and associated bushes wear and cause steering wobble, rear subframe mounts give up the ghost (self-steering rear end) and anti roll bar links ('dogbones') also go. All of these things are to be expected at 100k and higher.
If you're feeling flush, the Switchlogic mod (from Birds in Uxbridge) gives switch mode autos a semi-automatic paddle-shifty thing, which is a fairly nice compromise when you want to push on a bit *and* make the gearchange decisions.
Other stuff: electric seats can develop problems, usually to do with the cables (and their sheathes) that run from the motors to the gearing expanding/contracting with age. Weak batteries can cause bizarre issues, despite everything else seeming to be OK. On the V8s, rocker cover gaskets get weepy, allowing oil into the wells where the coils & plugs live, leading to misfires due to bad contacts. Steam cleaning to be avoided for same reason if possible. (Note to my local garage, grrr...)
Examine the bottom of the doors closely - around plastic strip along the bottom. The drain holes can block and the bottom edges can rot from the inside, hidden by the plastic strip. Despite that, I've been told the body is galvanised (or at least well rust-proofed) and shouldn't rust unless badly fixed/sprayed.
Errr, bit of a random brain dump that. You're unlikely to find all these things on one car, but they're all things that crop across a cross-section of high miles E34s. I've had most of 'em, but my car has been to the moon and back.
Lots of good info on www.bmwe34.net and www.bimmer.info.
Lastly, my personal opinion is that the V8s sound fabulous. It's just a shame the exhausts aren't a touch more vocal.
--Chris (E34 540i, 163k miles, mixed 20mpg - and I don't drive like a nun!)
On the 540i V8 the airbox has a restrictor pipe at the intake which I read was stop the 540i from embarrassing the M5 as regards power output, so BMW fitted the restrictor to keep the 540i honest.
If you look at the airbox the lower half has the restrictor pipe on it, behind the headlights on the drivers side.
It can be removed without cutting the airbox but mine was a very tight fit and took some wedging/levering with a flat bladed screwdriver to prise out. It's retained by expanding plastic clips which are hard to access once it's been pushed into the airbox, but can be got out with 'persuasion'.
Providing you still have the plastic headlight cover in place it'll still draw in cold outside air. I also fitted a K & N filter element in the airbox as well, and it's definately more sprightly at the very top end with a slightly more growly intake noise.
My 525i is a 'jack of all trades' and does countless different jobs as well as still being great to drive on your own. It's bomb-proof and so well built, and is the better all-rounder. However, the 540i is fun in a different 'bad to the bone' V8 road burner way
If you look at the airbox the lower half has the restrictor pipe on it, behind the headlights on the drivers side.
It can be removed without cutting the airbox but mine was a very tight fit and took some wedging/levering with a flat bladed screwdriver to prise out. It's retained by expanding plastic clips which are hard to access once it's been pushed into the airbox, but can be got out with 'persuasion'.
Providing you still have the plastic headlight cover in place it'll still draw in cold outside air. I also fitted a K & N filter element in the airbox as well, and it's definately more sprightly at the very top end with a slightly more growly intake noise.
My 525i is a 'jack of all trades' and does countless different jobs as well as still being great to drive on your own. It's bomb-proof and so well built, and is the better all-rounder. However, the 540i is fun in a different 'bad to the bone' V8 road burner way
Avoid the 12 valve SOHC cars (pre-24 valve cars) if you can.
I owned a 1989 530i for about 18 months and it was disappointingly slow below 4000rpm. Nice for cruising but not much else. As others have said, the 525 24-valve is the one to go for.
Build quality is very good and the engine is built to last. Mine felt like it would go on for ages. I think the E34 is still a handsome car, particularly the sport kitted ones and the M5 of course. Choose carefully and you'll get a lot of car for your money.
I owned a 1989 530i for about 18 months and it was disappointingly slow below 4000rpm. Nice for cruising but not much else. As others have said, the 525 24-valve is the one to go for.
Build quality is very good and the engine is built to last. Mine felt like it would go on for ages. I think the E34 is still a handsome car, particularly the sport kitted ones and the M5 of course. Choose carefully and you'll get a lot of car for your money.
Yes, the E34 was one of BMW's better models and stands the test of time well whilst still looking good, with a modern, aerodynamic shape.
They don't have any real weak spots and aren't so stuffed with electronics that you need a university degree in Electronic Engineering to sort any problems out.
They had galvanised panels so shouldn't rust in theory unless crashed and poorly repaired. Having said that some of the very early ones which, admittedly, are rather old now dating from 1988, are showing a few rust spots, notably on the boot lid.
Still, a little bit of cosmetic corrosion on an 18 year old car is notably better than either the E30 or E28 bodyshell managed-I owned both types and they rusted more than the E34 bodyshell.
Being heavy cars they can require suspension bits replacing, although it's not so much things breaking, just things getting a little 'tired' and 'baggy' round bends etc. Brakes can take a pounding on spirited driving with all that weight to slow down, and both discs and pads are classed as 'consumables', although they're not bank-breakingly expensive to sort out.
24v autos came with 5-speed GM autoboxes, and they're really good in my opinion and work better together than the earlier 12v engines and 4-speed ZF autos. The old 12v 520i 4-speed autos struggled with a small, peaky six pot trying to shift a heavy car through just 4 widely spaced ratios. The V8's came with 5-speed ZF autos, and I personally think the GM boxes have the edge on shift quality and decisiveness-the ZF 5-speeder can be a little indecisive and 'hunt' around for ratios. 540i autobox is 'sealed for life', a stupid idea in my opinion as you can't change the oil. The other 5-speeders can only have their oil levels checked at the main dealers as there's a special procedure.
If you've got the budget, a good late model 525i 24v Vanos-engined car is the one to go for, either manual or the excellent 5-speed auto. Efficient engine gives great economy on long motorway runs where the superior aerodynamics of the E34 bodyshell come into their own. A bit cumbersome round tight city streets but then you'd use a small hatchback for that, wouldn't you?
If you're really on a tight budget, you can't go wrong with a fully loaded old 535i SE as they're so cheap now and the big old engine is very simple to work on, although cam noise or worm cam/rockers etc means cylinder head off time and big labour bills, because although you can get a cam/rocker kit for around £200 ish, it takes much labour to fit everything, so don't buy a tappety six pot cos you'll regret it.
Later 24v small sixes had hydraulic tappets and twin cams, and these engines are not known for chewing up camshafts like their earlier 12v ones were. Any tappet noise on 24v engines is usually the hydraulic tappets themselves.
Cambelts were used only on the 518i 4-pot and 520i/525i 12v small sixes. Later 520i/525i 24v small sixes, all 530i/535i big sixes, and all 530i/540i V8's used timing chains, and these are not known for wearing out much either, although the M30 530i/535i big sixes used single-row timing chains which are not 100% bomb proof as they can stretch a little, although failure is a rarity. All the other chain-driven engines use stronger duplex double row timing chains for both the main chains and secondary chains, and I've never heard of any problems with these designs.
Final drive units are bomb-proof and steering boxes can have small amounts of play adjusted out, but too much adjustment alters the steering pre-load and makes the steering feel 'odd' and 'detached'. Steering play can also be caused by loose nut at base of adjustable steering column. Tighten it up only enough to remove the play-overtighten it and you won't be able to move the steering column in and out for adjustment
All in all great cars and getting cheaper by the minute. No need to buy a duffer cos there's so many good ones still out there
They don't have any real weak spots and aren't so stuffed with electronics that you need a university degree in Electronic Engineering to sort any problems out.
They had galvanised panels so shouldn't rust in theory unless crashed and poorly repaired. Having said that some of the very early ones which, admittedly, are rather old now dating from 1988, are showing a few rust spots, notably on the boot lid.
Still, a little bit of cosmetic corrosion on an 18 year old car is notably better than either the E30 or E28 bodyshell managed-I owned both types and they rusted more than the E34 bodyshell.
Being heavy cars they can require suspension bits replacing, although it's not so much things breaking, just things getting a little 'tired' and 'baggy' round bends etc. Brakes can take a pounding on spirited driving with all that weight to slow down, and both discs and pads are classed as 'consumables', although they're not bank-breakingly expensive to sort out.
24v autos came with 5-speed GM autoboxes, and they're really good in my opinion and work better together than the earlier 12v engines and 4-speed ZF autos. The old 12v 520i 4-speed autos struggled with a small, peaky six pot trying to shift a heavy car through just 4 widely spaced ratios. The V8's came with 5-speed ZF autos, and I personally think the GM boxes have the edge on shift quality and decisiveness-the ZF 5-speeder can be a little indecisive and 'hunt' around for ratios. 540i autobox is 'sealed for life', a stupid idea in my opinion as you can't change the oil. The other 5-speeders can only have their oil levels checked at the main dealers as there's a special procedure.
If you've got the budget, a good late model 525i 24v Vanos-engined car is the one to go for, either manual or the excellent 5-speed auto. Efficient engine gives great economy on long motorway runs where the superior aerodynamics of the E34 bodyshell come into their own. A bit cumbersome round tight city streets but then you'd use a small hatchback for that, wouldn't you?
If you're really on a tight budget, you can't go wrong with a fully loaded old 535i SE as they're so cheap now and the big old engine is very simple to work on, although cam noise or worm cam/rockers etc means cylinder head off time and big labour bills, because although you can get a cam/rocker kit for around £200 ish, it takes much labour to fit everything, so don't buy a tappety six pot cos you'll regret it.
Later 24v small sixes had hydraulic tappets and twin cams, and these engines are not known for chewing up camshafts like their earlier 12v ones were. Any tappet noise on 24v engines is usually the hydraulic tappets themselves.
Cambelts were used only on the 518i 4-pot and 520i/525i 12v small sixes. Later 520i/525i 24v small sixes, all 530i/535i big sixes, and all 530i/540i V8's used timing chains, and these are not known for wearing out much either, although the M30 530i/535i big sixes used single-row timing chains which are not 100% bomb proof as they can stretch a little, although failure is a rarity. All the other chain-driven engines use stronger duplex double row timing chains for both the main chains and secondary chains, and I've never heard of any problems with these designs.
Final drive units are bomb-proof and steering boxes can have small amounts of play adjusted out, but too much adjustment alters the steering pre-load and makes the steering feel 'odd' and 'detached'. Steering play can also be caused by loose nut at base of adjustable steering column. Tighten it up only enough to remove the play-overtighten it and you won't be able to move the steering column in and out for adjustment
All in all great cars and getting cheaper by the minute. No need to buy a duffer cos there's so many good ones still out there
RedOctober said:
I........535i SE as they're so cheap now and the big old engine is very simple to work on, although cam noise or worm cam/rockers etc means cylinder head off time and big labour bills, because although you can get a cam/rocker kit for around £200 ish, it takes much labour to fit everything, so don't buy a tappety six pot cos you'll regret it.
Wish i had know this, mine has started to sound a tappety now. Any idea on costs to fix?? I know its new can shaft, followers, head off, new gasket etc etc..
Nice car otherwise, handles well and goes well. Think a 540 next if i ever change it.
Paddy
Check your cam lobes are actually worn before doing anything else. Whip the rocker cover off and look at the lobes. Sometimes they can just be tightened up by adjusting the valve clearances.
On the big six (M30) engine, there was a slight design flaw on the earlier ones. The camshaft oil spray bar was bolted to the cylinder head by 2 hollow bolts with soft aluminium washers.
Over the years the soft washers 'settle' and the 2 bolts work loose, starving the oil spary bar and camshaft of oil, leading to cam and rocker wear.
BMW brought out a mod to fit different non squashy washers, but by then the damage was already done.
I once changed a camshaft and rockers on a small BMW six pot and it wasn't a pleasant job. The bits weren't expensive but the head had to come off and trying to remove the camshaft past all those rockers and then fit the new one was a pain in the neck and took a good while.
You may just be lucky and get away with tightening up the valve clearances. If the cam is worn, the rockers will be worn as well. What happens is that the hardened surfaces wear out when starved of oil, exposing the softer metal beneath, which then wears out much faster, and I've seen cam lobes worn almost flat with excessive wear.
Annoying that such a simple fault could cause such expensive problems.
On the small sixes with 24v twin-cam heads, BMW committed another short-sighted engineering decision, namely to fit water pumps with plasic impellers instead of metal ones.
Over the years, the plastic impeller cracks where it grips the water pump shaft inside the water pump. Everything looks fine from the outside as looking under the bonnet sees the water pump appearing to turn over fine.
Inside the water pump, however, the impeller has stopped pumping water and the engine suddenly starts overheating rapidly and the heaters blow cold air only as there's no coolant flow anywhere.
This happened to my '95 24v Vanos 525i touring one evening. There I was tooling along and next thing the temperature gauge is shooting skywards. Fortunately I was on a quiet road so stopped the car rapidly and switched off the engine.
I was near home so walked home up a big hill and let the engine cool down. I knew what had happened as I read all about the problem earlier. After an hour I went back and brought the car home ok.
Whipped the water pump off the next day and sure enough the plastic impeller had cracked and was not turning with the metal shaft. I replaced it with a new metal-impeller water pump and it's been fine ever since.
I still can't believe that BMW, with all it's engineering integrity, would fit such a compromised part in such a critical application.
Had I been on a packed rush hour motorway and it failed then, I would have overheated the engine and most probably warped the expensive 24v cylinder head, all for the sake of a piece of plastic.
BMW saved a few pence and a few measly grammes of weight with this flawed design, and in doing so risked owners having potentially very expensive damage to their engines.
Oops, gone off at a tangent here Just hope your fault is simply valve clearance adjustment.
Alex
On the big six (M30) engine, there was a slight design flaw on the earlier ones. The camshaft oil spray bar was bolted to the cylinder head by 2 hollow bolts with soft aluminium washers.
Over the years the soft washers 'settle' and the 2 bolts work loose, starving the oil spary bar and camshaft of oil, leading to cam and rocker wear.
BMW brought out a mod to fit different non squashy washers, but by then the damage was already done.
I once changed a camshaft and rockers on a small BMW six pot and it wasn't a pleasant job. The bits weren't expensive but the head had to come off and trying to remove the camshaft past all those rockers and then fit the new one was a pain in the neck and took a good while.
You may just be lucky and get away with tightening up the valve clearances. If the cam is worn, the rockers will be worn as well. What happens is that the hardened surfaces wear out when starved of oil, exposing the softer metal beneath, which then wears out much faster, and I've seen cam lobes worn almost flat with excessive wear.
Annoying that such a simple fault could cause such expensive problems.
On the small sixes with 24v twin-cam heads, BMW committed another short-sighted engineering decision, namely to fit water pumps with plasic impellers instead of metal ones.
Over the years, the plastic impeller cracks where it grips the water pump shaft inside the water pump. Everything looks fine from the outside as looking under the bonnet sees the water pump appearing to turn over fine.
Inside the water pump, however, the impeller has stopped pumping water and the engine suddenly starts overheating rapidly and the heaters blow cold air only as there's no coolant flow anywhere.
This happened to my '95 24v Vanos 525i touring one evening. There I was tooling along and next thing the temperature gauge is shooting skywards. Fortunately I was on a quiet road so stopped the car rapidly and switched off the engine.
I was near home so walked home up a big hill and let the engine cool down. I knew what had happened as I read all about the problem earlier. After an hour I went back and brought the car home ok.
Whipped the water pump off the next day and sure enough the plastic impeller had cracked and was not turning with the metal shaft. I replaced it with a new metal-impeller water pump and it's been fine ever since.
I still can't believe that BMW, with all it's engineering integrity, would fit such a compromised part in such a critical application.
Had I been on a packed rush hour motorway and it failed then, I would have overheated the engine and most probably warped the expensive 24v cylinder head, all for the sake of a piece of plastic.
BMW saved a few pence and a few measly grammes of weight with this flawed design, and in doing so risked owners having potentially very expensive damage to their engines.
Oops, gone off at a tangent here
Just hope your fault is simply valve clearance adjustment. Alex
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