One Most Important Thing To Look For on a M50 525i

[Mordan]

Hi, there on the top of your head, what is the most important thing I have to check when buying a used 525i (1991) with a M50 24v?


The 518i M40 I bought last month fails on me because of cylinder head damage. I don't wanna get screwed again.

Thanks!

PS: I'm not lazy I'm looking around...just want a short quick input to check on the internet about specific failures.

[pingu]

Try:

http://www.bmwe34.net/e34main/trouble/what_will_break.htm

[Ross]

Water pumps on that one are prone to failure, you already know the consequences of overheating.
All the usual points are covered on this board with a little looking around.
A thorough inspection by someone FAMILIAR with E34s is the best insurance of not getting someone elses troubles. Documented maintenance(not fixing) is next best.

[Dave M]

Along with the water pump, get as thorough an inspection of engine health as possible. The M50 will fail if overheated (exhaust valve seats in cylinder head are a weak spot). It may run fine during a test drive, but could be slowly burning coolant through a hairline crack, or mixing oil and coolant etc.

Questions to ask:

Does it use any coolant? Does it leak or burn any oil? Oil analysis to check for coolant. Compression test, leak down test etc. May seem overkill, but serious issues may go unnoticed in a test drive. I did buy a M50 with a cracked head, which ran like a top, but drank coolant. They’ll run forever as long as you watch that temp needle.

Dave

[healtoeit]

Does it use any coolant? I did buy a M50 with a cracked head, which ran like a top, but drank coolant.
Dave, is a cracked block a common weak point on these engines? My car is leaking coolant and I can't seem to find the source... The engine plug looked ok, all the hoses and radiator fine any suggestions?

[healtoeit]

Hi, there on the top of your head, what is the most important thing I have to check when buying a used 525i (1991) with a M50 24v?
Regular oil changes is what I say to look for. What everyone else so far has said as well. This engine is bulletproof, variations of it have been used in almost every model BMW pre Bangel... Even the e46 M3 CSL (according to Wik.)

[Dave M]

Dave, is a cracked block a common weak point on these engines? My car is leaking coolant and I can't seem to find the source... The engine plug looked ok, all the hoses and radiator fine any suggestions?

Can't say I've heard of a single M50 block failure. Someone here may have, but its not a common occcurance. The cylinder heads are definitely the more fragile member (aluminum head mated to a cast iron block cooling at different rates).

Anyhow, without a sign of external leakage, either its:

1) evaporating on a hot part of the engine before pooling somewhere
2) seaping slowly out of the heater core and evaporating
2) leaving via your exhaust (you're burning it)
3) in your oil

How much coolant are you losing???
Have you had the system pressure tested while on a hoist???
What do your spark plugs look like (any white crusty deposits)???
Does the engine miss at all (hesitate for a brief moment at certain rpms)??

Dave

[repenttokyo]

anyone else noticed that the time problems are starting to creep up into bimmernut from bimmer.info?

[Mordan]

Does the engine miss at all (hesitate for a brief moment at certain rpms)??

Dave
I used to have that on the M40.

thx all for your answers. but there are things I won't be able to check unless I pay an expert. 140 euros for a full test. worth it?

Anyway here is the beast for 2400 euros... the guy says he sells it because he bought a house and a more powerful and lighter car (he bought a Volkswagen)

Here are the pics

http://pic.autoscout24.net/images-big/815/322/0132322815001.jpg
http://pic.autoscout24.net/images-big/815/322/0132322815002.jpg
http://pic.autoscout24.net/images-big/815/322/0132322815003.jpg

http://pic.autoscout24.net/images-big/815/322/0132322815004.jpg

he just told me on the phone the car was CT OK(admin document saying the car can drive ) back in January. never drove since because no more license plate for the car.
242k kms = 150k miles

[Mordan]

http://pic.autoscout24.net/images-big/815/322/0132322815005.jpg
http://pic.autoscout24.net/images-big/815/322/0132322815006.jpg

[Ferret]

<snip>

Is this a genuine AC!?


She's a good looking well-looked after example, however there's just one or two things that are making me twich...

...where's the battery I thought all M50 engine cars had it under the bonnet? (Read: who/why was it moved to under the rear seat)

Has it got a custom exhaust on it? The tail pipes look too small for a 525i - either that or my brain has just melted in the heat we're having here.

I didnt realise two-tone leather was an option, unless this has had a transplant from a genuine AC?


Get a picture of the manufacturing plate under the bonnet - I think we'd all like to see if this is a genuine AC - if it is, snatch it up after a few cursory checks.

[Dave M]

I used to have that on the M40.

thx all for your answers. but there are things I won't be able to check unless I pay an expert. 140 euros for a full test. worth it?




If you don't trust yourself to identify potential problems, pay the expert. Its well worth the money for the peace of mind. Its a beautiful car, don't let it slip away........................

Dave

[Ross]

The reason you pay the expert 140 quid is to save you from thousands later.
If I were selling that car and were confident of it's condition I would agree to pay for the inspection if failed.

[Dave M]

anyone else noticed that the time problems are starting to creep up into bimmernut from bimmer.info?

I love how this post always stay at the bottom :D

EDIT: $hit, I bumped it.

[repenttokyo]

that tail wing is actually really tasteful, kudos.

[bsell]

I used to have that on the M40.

thx all for your answers. but there are things I won't be able to check unless I pay an expert. 140 euros for a full test. worth it?

Anyway here is the beast for 2400 euros... the guy says he sells it because he bought a house and a more powerful and lighter car (he bought a Volkswagen)

Here are the pics

http://pic.autoscout24.net/images-big/815/322/0132322815001.jpg
http://pic.autoscout24.net/images-big/815/322/0132322815002.jpg
http://pic.autoscout24.net/images-big/815/322/0132322815003.jpg

http://pic.autoscout24.net/images-big/815/322/0132322815004.jpg

he just told me on the phone the car was CT OK(admin document saying the car can drive ) back in January. never drove since because no more license plate for the car.
242k kms = 150k miles

For 6% of the purchase price, the mechanic's inspection may save you from 94% of the headache...as long as the mechanic does everything they promise!

She looks pretty clean for a pre-airbag car. Too bad the driver's seat is torn.

I have never seen that trunk configuration before. The engine bay looks just like by '95 525's so don't worry too much about the battery location mentioned elsewhere.

Brian

[Mordan]

Get a picture of the manufacturing plate under the bonnet - I think we'd all like to see if this is a genuine AC - if it is, snatch it up after a few cursory checks.

OK I will do that. is it that plate stating the color of the car? If not, where should I look on my 518i so I already know where to look when I will go see that 525. thx.

btw what is AC? some custom modifications like Alpina?

[Mordan]

she was sold in June 1992

I don't see where the battery would fit under the bonnet.

I actually like the fact she has no airbags. more space and less hassle.

I take your advice and use the service of a mechanics

[repenttokyo]

she was sold in June 1992

I don't see where the battery would fit under the bonnet.


as you are facing the car, left of the engine, on a tray beside the washer reservoir.

[Mordan]

as you are facing the car, left of the engine, on a tray beside the washer reservoir.

that's where it is on my 518i but the M40 is really small. never saw a M50 with my eyes real life.

so why would the battery be under the back seats?

[attack eagle]

does it have a clean title, no liens no salvage... and are you the registered title holder?

if not who cares about anything else???

[healtoeit]

...where's the battery I thought all M50 engine cars had it under the bonnet? (Read: who/why was it moved to under the rear seat)

The battery is always under the rear seat... BMW did this for weight distribution

[healtoeit]

so why would the battery be under the back seats?
thats how mine is...And that is where it belongs!

[cammo]

ive never seen a tail wing like that. pretty awesome. wonder if creeps in the boot space. n would it affect where the tools go?

[healtoeit]

btw what is AC? some custom modifications like Alpina?
Yes,
http://www.ac-schnitzer.de/en/
enjoy :D

[BMWDriver]

Very nice car*! Impeccable even. Wonderful looking interior. A manual is great for the M50. From 1st gear, 2000 rpm gives a reasonnable start; 3000 a quicker one, and 4500-5500 will thrust you in your seat. 1000-1500 rpms is a bit like riding a tortus, but still ok.

Does Schnitzer even bother with a 2.5 ?

The battery on this one is under the seat; the giveaway is the positive pole that's close to the windshield, with a red cap on it and the + sign.

[myles]

Early M50 models have it in the engine bay, the same as the M20, but from sometime around 4/91 they put the battery under the rear seat like M30 and M60 models.

edit - I thought the forum clock was working again? Mine has just gone an hour early again.

[Ferret]

The battery is always under the rear seat... BMW did this for weight distribution

Lies! :D

Every M50 engine car I've seen or driven the battery was under the right hand side of the bonnet/hood, not under the rear seat!

[Ferret]

thats how mine is...And that is where it belongs!

I wonder if there is a difference between european and US versions then...

[Ross]

Lies! :D

Every M50 engine car I've seen or driven the battery was under the right hand side of the bonnet/hood, not under the rear seat!
Yeah, but every E34 you've driven has the steering wheel on the wrong side too.

[Ferret]

but from sometime around 4/91 they put the battery under the rear seat like M30 and M60 models.

:o mine was an 09/92 model

[Mordan]

Does it use any coolant? Does it leak or burn any oil? Oil analysis to check for coolant. Compression test, leak down test etc. May seem overkill, but serious issues may go unnoticed in a test drive. I did buy a M50 with a cracked head, which ran like a top, but drank coolant. They’ll run forever as long as you watch that temp needle.

Dave

Hello, I phoned the Mobile Check Expert. He told me they cannot do a compression test on the engine. but they do it on the cooling system.
will that be enough? What is the purpose of the compression test on the engine?

[repenttokyo]

Hello, I phoned the Mobile Check Expert. He told me they cannot do a compression test on the engine. but they do it on the cooling system.
will that be enough? What is the purpose of the compression test on the engine?


i have no idea what a compression test on a cooling system is. perhaps he meant a 'pressure test'.

a compression testing on the engine checks each cylinder to make sure that it is in good shape internally, and isn't leaking, or has worn out rings, etc.

[Mordan]

background of the guy
young, short, has a girlfriend, lives in the house of his mother, he has 2 pitbulls puppies. dirty old house. he drives an Corrado VW, but the car is at the garage. he bought a house, the walls of house actually because there is nothing inside the house. lol. he bought the car 8 months ago he tells me. drove 15 000 kms with it. good engine he tells me. he never serviced the car. duh. I was like wtf?
car service history 'null'. last CT OK actually is November 2006. ages ago. he does not have any invoice, though he said he changed the front suspensions.

I came alone first without an expert.

pros: paint is in overall good condition.

cons:
1) engine heavily shakes the car the first 5 minutes. he says it is because of the holes next to the air filter. purpose? previous owner drilled holes for making more noise. pathetic attention seeker. omg.
2) left rear of the car makes noise when bumping on the road. he says it is the suspension and will cost me only 100 euros
3) the clutch is nearly gone. the chrome top is really chavy and ugly.
4) radio cables are a mess. no radio though he claims it is his car.
5) engine make sometimes noises I dislike.
6) engine looks clean but oils is leaking in some places, see pics.
7) trunk has 3 big spots of dirty oil/fuel. were already there when he bought the car. I know by experience it is hard to remove these.
8) he told me he bought the car to a mechanics who set up the kit? I asked him if it is was an original AC and he could not answer clearly. I did not see many numbers under the bonnet.

We went for a drive. Halfway, I asked him to drive and He would not want me to drive. he said "if you buy the car, you can drive it all you want" lol omg.
I drove the car anyway. Not too bad. But the gear pedal is really hard to press down.

I'm a bit disappointed. what should I do? Go on with an expert? Ask to drop the price?

http://www.mordan.biz/bmw/bmw_e34_marchin_num_1.jpg
http://www.mordan.biz/bmw/bmw_e34_marchin_num_2.jpg

http://www.mordan.biz/bmw/bmw_e34_marchin_oil_1.jpg
http://www.mordan.biz/bmw/bmw_e34_marchin_oil_2.jpg

[Mordan]

http://www.mordan.biz/bmw/bmw_e34_marchin_cons_1.jpg
http://www.mordan.biz/bmw/bmw_e34_marchin_cons_2.jpg
http://www.mordan.biz/bmw/bmw_e34_marchin_rust_trunk.jpg
http://www.mordan.biz/bmw/bmw_e34_marchin_rust_1.jpg

rust at the bottom of all door, especially the driver's.

[Mordan]

Very nice car*! Impeccable even. Wonderful looking interior.

I thought the same before actually seeing it. pics are deceiving. I don't really like the interior anymore. All this white, not so white anymore felt so dirty. I prefer black. or a well looked after beige.

[cammo]

looks like a great car. if ya can get it cheap, and have the money to fix most if not all things on that. id do it

[Mordan]

looks like a great car. if ya can get it cheap, and have the money to fix most if not all things on that. id do it

cammo how much is cheap for you?
see my post on my first visit. how much did you buy your 525i?

[Dave M]

I have to make this quick, but I'm sure others will have much to say about your observations.

Besides you not really liking gthe color scheme,

1) When you state "deep rust" at the door bottom, you may be looking for a new door or door skin in order to remedy that. All the others are likely rusted under the bottom door strips, requiring attention.

2) The rest of the car seems far from rust free. While you state the paint looks good, I'd beg to differ given the amount of rust you found in one visit.

3) As the "engine make sometimes noises I dislike" and it runs like $hit for the first 5 minutes, I'd be taking to someone who knnows what their talking about. No offence, but it sounds like neither the seller nor potential purchaser are in a position to diagnose whats the F'uk is going on with the ting. For fun, grab a pice of duct tape, cover the holes at the air filter (housing??) and drive it again.

4) Is the cutch slipping while in gear, or is the pedal simply heavy?? These are two quite different problems. If its the clutch, take $500+ off the price.

5) Rear suspension = 100 euros. What is it he thinks is causing the issue? It is advisable to replace suspension components in pairs. If he does knnow whats wrong with it, douuble the price to do the other side.

You might want to drop this one, or offer significatly less and have some fun fixing it yourself.

Dave

[BMWDriver]

The engine bay is mostly clean, which would usually be a good sign that the owner before him took good care of it. You could always swap the interior of your current 518 (if you still have it).

The dim OBC pixels are likely just that there is a bulb to change.

I had put as much in repairs on my e34 as I had paid for it (3800$ Canadian) within about a year and a half. Now that the big stuff's been taken care of, its running sweet. The only problem I have nowadays is rust, and I kind of like dealing with it. It needs attention, and I feel terribly proud every time I do something that makes it better.

But, keep looking. You might find one that's better and that could save you some trouble.

[e34.535i.sport]

Walk away...

It sounds like you've already talked yourself out of it. Only buy the car if you're TOTALLY happy with it or you'll regret it. I searched for SO long before I settled on my car and I travelled far and wide to find it. Once I drove it I knew it was the car for me.

For me personally no service history = no purchase. Even with an example that's been taken care of you will have repairs to do, one that hasn't will just be a pain in the asse.

+ the current owner seems like a douche bag too.

[anonymous1]

Hi,

Looks like you would need to do quite a few things to this vehicle to get it up to the standard you seem to want and not all of them are cheap, especially if you will be paying someone the labour to do the work for you. I personally probably wouldn't bother.

The sticker in the engine states the vehicle is a 525iA - I was lead to believe this meant it was an auto and the interior shows manual box (someone may be able to correct me if I am wrong on this point). Has this been converted to a manual? (Just wondering in case the VIN has been tampered with on the vehicle - seen as the current owner already seems a bit on the dodgy side!)

[nirvana19]

"525iA"

You said its a manual right (it has a clutch...). It wasn't originally, something is up. At the very least a manual transmission conversion (not necessarily a bad thing) but the history of this car does seem a bit sketchy. From the pictures it certainly does look nice, though the cheap plastic modifications you mention would turn me off. I certainly don't have a verdict but you want to take a closer look at this, check underneath the car especially. If YOU think all is good and don't find glaring problems, then get a professional to inspect the car as well before making a decision. Even if you get a really good deal on the car it could cost you more than you paid to repair something.

[Mordan]

"525iA"


thanks you all guys for your answers.
didn't noticed the A!. goddammit the very fact it has been changed from automatic to manual pretty much killed it.

Yea I just talked out of it in my previous post. It is just to the measure of my disappointment. It looked so great on the picture.

why would Schnitzer or anyone change an Automatic to a Manual?

There are way too many question marks with the car and the guy.
Someone mentioned about driving the car and knewing it was the One. well I felt the exact opposite when I first sit in the driver's seat. oh well... got to move on.

[Ferret]

thanks you all guys for your answers.
didn't noticed the A!. goddammit the very fact it has been changed from automatic to manual pretty much killed it.

Yea I just talked out of it in my previous post. It is just to the measure of my disappointment. It looked so great on the picture.

why would Schnitzer or anyone change an Automatic to a Manual?

There are way too many question marks with the car and the guy.
Someone mentioned about driving the car and knewing it was the One. well I felt the exact opposite when I first sit in the driver's seat. oh well... got to move on.

Bah, if it's nice looking from afar and that's all, just dont bother with it mate, walk away and find another one.

Seriously if it's running like a dog for the first 5 minutes, who knows how long it's been doing that and how hard it's been driven while not running right.

The guy's just ********ting you to your face by the sound of it, as he suggests it could be just simple things wrong with it -but are you willing to risk he's a lying toerag?

One thing with M50's : if they dont run clean and crisp when you inspect them, walk away and never look back. The damage M50s can pick up and not display overly obvious symptoms is staggering.

[e34.535i.sport]

It looked so great on the picture.


Hey, there's plenty more great looking e34's out there so don't worry about leaving this one - be patient and you'll be happier in the long run.

[whiskychaser]

Lies! :D

Every M50 engine car I've seen or driven the battery was under the right hand side of the bonnet/hood, not under the rear seat!
You can check mine any time you are up this way. And you can buy the beer all night if you can find the battery under the bonnet:D I think you have a point about the tail pipes. Lovely motor but I wouldnt touch one that had a tow bar on it

[Mordan]

You can check mine any time you are up this way. And you can buy the beer all night if you can find the battery under the bonnet:D I think you have a point about the tail pipes. Lovely motor but I wouldnt touch one that had a tow bar on it

if a M50 can't have a tow bar, what BMW can? :(
:)

[whiskychaser]

if a M50 can't have a tow bar, what BMW can? :(
:)
You would probably agree its OK to pull 75% of the car's weight. Lets say thats 1200kg. But if I asked you to drive your car with ten big guys in it (10 x 120kg) you would say I'm a loony. I just dont think it does the engine, drive train or suspension any good so I avoid cars with hitches like the plague.

[Mordan]

You would probably agree its OK to pull 75% of the car's weight. Lets say thats 1200kg. But if I asked you to drive your car with ten big guys in it (10 x 120kg) you would say I'm a loony. I just dont think it does the engine, drive train or suspension any good so I avoid cars with hitches like the plague.

well indeed I wouldn't like ten big guys in my car. but the thing rests on at least 2 wheels if not 4.
10% of the time.
engine would only suffers during slopes if you respect your car and don't race while towing something :)

[whiskychaser]

well indeed I wouldn't like ten big guys in my car. but the thing rests on at least 2 wheels if not 4.
10% of the time.
engine would only suffers during slopes if you respect your car and don't race while towing something :)
OK, ten guys IN the car was a joke. But its still what you are asking the car to pull - and stop. You may be careful but the PO(s) may not. By the way, I dont think anybody mentioned the timing chains on the M50. They dont snap like a belt but can hop the sprockets with the same results. So have a listen for any rattles up front.

[e34.535i.sport]

well indeed I wouldn't like ten big guys in my car. but the thing rests on at least 2 wheels if not 4.
10% of the time.
engine would only suffers during slopes if you respect your car and don't race while towing something :)

I'm afraid I'm with the scotch on this one... While I agree with the wheels on the trailer taking some of the weight - besides the engine working harder there must be stress on the chassis and drive pulling extra weight like that. I steer clear of tow bar cars too to be honest. Plus they look ****.