BMW M5 Forum and M6 Forums banner

1 - 20 of 93 Posts

·
Registered
Joined
·
80 Posts
Discussion Starter #1
Hi all,

I'm new to this forum, I purchased my second E34 M5 on 1st of January 2011 and loved it.

After two days and covering 80 miles I thought I'd take it for a top end run, it got to 165 then on the over run starting misfiring.

I've started to look into it and carried out a compression test, all cylinders were just under 200psi apart from no 4 at 0 psi.

I haven't had time to investigate it further and take the cylinder head off yet.

If it turns out I need to replace the piston etc does anyone know the best place to find these parts?

As you can imagine I'm starting to get worried about how much this could cost me to put right.

Has anyone had a similar problem?

The car has done 114000 miles and seemed to be a good example at the time of purchase.

Any help would be much appreciated.
 

·
Registered
Joined
·
459 Posts
so you hit 165 in winter :eek:

you need head gasket set and oil pan gasket set.

you may need a piston, not just rings. 0 psi reminds me of a melt or seriously damaged piston.

cylinder wall may be damaged as well. hitting 165 puts an old engine under severe stress and the sustained load may have
caused a damage to the cylinder walls as well.

lets get the engine opened.
 

·
Registered
Joined
·
80 Posts
Discussion Starter #3
Yes, obviously I'll buy a gasket set. I'm assuming it has melted a piston but only time will tell. It's going to be another week now before I get a chance to have a look.
Are these engines any harder to work on than any other because some people say there a nightmare?
 

·
Registered
Joined
·
80 Posts
Discussion Starter #4
I didn't buy an M5 and pay £2000 insurance to keep to the speed limits :)
 

·
Moderator
Joined
·
10,458 Posts
member davidoli had the same thing happen, cyl #4 if i remember correctly.

I believe there's a big vacuum hose, either crankcase vent or brake booster at #4's throttle body. I bet that hose is failing, and there is a vac leak that caused a lean condition, leading to a burnt valve and possibly other damage to the cyl.
 
  • Like
Reactions: e34m5gsxr1000

·
Registered
Joined
·
80 Posts
Discussion Starter #6
Ok nice one I'll have a look into it. I was surprised it developed a problem so soon the previous owner seems to have looked after it and I've owned 8 E34's and never really had a problem some of them have had nearly 200k on the clock.
Many thanks.
 

·
Registered
Joined
·
7,667 Posts
Off the top of my head , I think mine was piston #5 and the ingredients were very similar to your own , although I was just changing up from 4th to 5th and getting warmed up when mine let out a puff of smoke and started missing .........

The thread is on here somewhere ...... It was a couple of years ago ....... Hole / melted piston !

You may get away with simply renewing the one piston and a hone ........ Obviously , an inspection will reveal all !

p.s. I don't judge you for wanting to see what she went like , but like to give all of my E34 M5s a good going over before driving them hard ( especially up top ) now , as I've had a few let go due to various items not being addressed prior to being driven hard !

p.p.s. was it the L reg ( L***v*u ) ?

p.p.p.s Welcome to the forum and I hope that you can get this resolved without too much pain !
 

·
Registered
Joined
·
80 Posts
Discussion Starter #8
Hi davidoli,

I was just looking on your profile to see if I could find the post. I know I'm to blame for giving it too much stick but that's what satisfies me. I pay nearly £300 a month to insure my car and bike so might as well make the most of it.

Yes it is the one, it was for sale for 15 hours and I turned up and bought it. I got it a fair bit less than advertised for so don't mind spending a bit on it. There doesn't seem to be many about these days so I'm going to hold on to it and bite the bullet it took me a good couple of months of looking every day to find it.

So if I need to buy 1 piston where is the best place to go?

How much do you think I will need to spend to get it back on the road if I do all the work myself and it's just a piston?

Thanks for all your help !

Ps I can tell you've been looking around :)
 

·
Registered
Joined
·
7,667 Posts
The problem with a lot of these E34 M5s coming up for sale now , is that they haven't been used regularly and have been sitting around going stale .

I liken it to a marathon runner who has decided to take a couple of years out . He sits on the sofa and watches Discovery Channel most days and occasionally gets up to go to the bathroom or kitchen . After a couple of years of this , his good friend from the glory days suggests that he enter the London Marathon and , without training , he tries to better his 2hr 4 min personal best .........

After 17.4 miles ( bloody hell , he did well ! ) , he has a heart attack and lies helpless on Tower Bridge !

In hindsight , he was asking a lot of himself !

Your new car has covered 8t miles in 3 years and probably got the shock of it's life when you jumped in !

Moving on .......... I have a standard 94.555mm piston for you , if required , although you'll only really know what you need after a fair few hours getting that head off !
 

·
Registered
Joined
·
1,373 Posts
very much liking your analogy Mr Olias ;-)

"e34m5gsxr1000" (sorry don't know your name), really sorry you've had a early failure :-(, but welcome to this board, the people on here are a good bunch, and quite a few UK members. Mr Olias has lot's of spares btw and is a good guy.

We've all found that the E34 M5 really benefits from regular use, which helps justify the costs of very regular maintenance.... much more than people expect / are used to with modern cars.

As an example, rev limit - I won't take my car near the rev limiter if the valve clearances haven't been checked fairly recently, if the car hasn't been running perfectly recently, unless I know the oil is full (ie checked that day) etc etc.

Personally I think preventative maintenance is key.... eg, I've just had all the water cooling system replaced, (hoses, radiator etc). I knew the rad wasn't perfect, but was surprised at the condition of it once we had it off and could examine it closely... ditto some of the hoses. I did this after reading on here what seemed to fail at 100k miles mark (mine is 93k). Next is the water pump... couldn't quite stretch to it at the time

The engine is basically everything in these cars, if the engine goes the car is almost worthless imho... a board member on here recently paid out a small fortune to replace his 3.6 unit with a new one... and the person in question definitely doesn't skimp on maintenance and uses a well respected E34 specialist for that work.
 

·
Registered
Joined
·
80 Posts
Discussion Starter #11
David - That's a good way to describe it, your right in what you say, looking back i should of taken a little more care and maybe spent a bit more time giving it some love before driving it to hard but whats done is done. I tried to reply to your message but it wouldn't let me as i haven't written enough posts. Thanks for that i'll be in touch.

1day - My problem is i haven't had enough mechanically sympathy in the past ( although i used to be a bike technician) and have always sold a car if it had to many problems. I am determind to keep this car and give it the tlc it deserves. Thanks for your welcome.

All the best to you both,

Alex
 

·
Registered
Joined
·
1,972 Posts
Get ready to kiss goodbye to best part of 3k to just fix it! Also pay mind to the fact there will be other bits that won't be sorted and will be weak compared to what you do.

Is there a chip in there? The fuelling might be a bit on the lean side resulting in a melt

If you rebuild the bottom end of a car it is then stronger than the top end which then becomes the weak part

If budget allows I would replace all serviceable items and anything else you can while it's apart

Rings, all bearings, oil pump, clutch and flywheel,all seals and gaskets, timing chain, reseat all valves clean the inlet and outlet ports, recondition the throttle bodies, replace all hoses, vacuum and coolant, radiator,thermostat, redo all shims, prob a good idea to do the wiper linkage while it's easy to do, also all bottles.:happybirt

I did all of this, ran her in for 500 miles, then another 1000, then another 1000, then still took it easy for a while. I still don't batter her and that was 40k and 8 years ago.:wroom:

My bill for parts was over 4k! Again that was 8 years ago. God knows what it would cost now:crying::crying:

Have to say best of luck old bean and keep us ll informed.
 

·
Registered
Joined
·
80 Posts
Discussion Starter #13
Wow... To be honest I will do the minimum to get it back on the road and failing that it will go on eBay for 0.99p no reserve.

As much as I love E34 M5's I haven't got the time or patients to carry out all that work. I might even treat it to a set of gaskets :)

If I had a big garage and earned £100,000 a year then I might of considered it + some forced induction.
 

·
Registered
Joined
·
1,209 Posts
I'm afraid Steve is right. I think his £3k estimate is conservative to say the least. To do a proper full rebuild with new parts will cost you around £7k.

When my engine blew I looked at all the options and decided on a new long engine from BMW, it was not cheap at all.

Other options are breaking the car and buying another with the proceeds or fitting a second hand engine.

Good luck with whatever you decide to do.
 

·
Registered
Joined
·
80 Posts
Discussion Starter #15
Thanks,

I'll do what needs to be done then take it from there, I'm 21 and dont have a spare £7000 in the bank. If it keeps letting me down i'll get rid of it but it's got to be worth a try 1st.

I thought about another engine but thats not going to come cheap and also you never know whhat thats been through and how long its going to last....

Hopefully i can get away with the minimin and get it back on the road where it deserves!

The M5 is only for winter anyway, i've got the Suzuki GSXR1000 for serious RELIABLE fun! :)
 

·
Registered
Joined
·
80 Posts
Discussion Starter #16
Does anyone know where i can get a workshop manual from? i've already downloaded the basic S38B38 changes and technical data manual..
 

·
Premium Member
Joined
·
2,941 Posts
Thanks,

I'll do what needs to be done then take it from there, I'm 21 and dont have a spare £7000 in the bank. If it keeps letting me down i'll get rid of it but it's got to be worth a try 1st.

I thought about another engine but thats not going to come cheap and also you never know whhat thats been through and how long its going to last....
I am sorry, but with those credentials it is wise to ask yourself weather or not an E34 M5 is an appropriate car for you. There is no such thing as a cheap M5, regardless of any generation. With a budget repair, you will end up doing the same thing twice. Then it will let you down twice; maybe you should concider to sell her and get an E34 525i M50 for the money. These are much cheaper to maintain and don't require the preventive maintenance that you not wish to spend.
 

·
Registered
Joined
·
80 Posts
Discussion Starter #18
Raymond,

Sorry for wanting to own an M5 but not having thousands of pounds in the bank, i expected some high running costs but bmw's are generally reliable and i didn't expect a major problem after covering just 80 miles.

I had no problems with my last E34 M5 or my E36 M3.

I bought the car to enjoy it not to be anal and spend loads of money on it for the sake of it!!!

It's funny you should say that, ive owned about 10 cars with M50 engines and never had a major problem.
 

·
Registered
Joined
·
1,972 Posts
You can't beat a man for wanting one of these! I wish I had one when I was 21 but my experience's make me glad I didn't financially. A solid e30 320i SE was the steed back then.

These are notoriously expensive to maintain, and upkeep is paramount for their longevity. A lot of us are normal guys that turn to snobs when it comes to these. Ultimately we will help if we can but will cringe if what we feel should be done isn't. This is possibly why the engine went due to maintenance not being correctly carried out. This is not to say the previous owner didn't but it just takes one shim to be wrong in spec to have disastrous results.

Start by finding out what the cause was and go from there. Hopefully no damage to block and head then expense can be better for you.

Good luck and keep us informed and throw whatever concerns or questions at us and hopefully somebody can help:byebye:
 

·
Registered
Joined
·
1,373 Posts
Much as it pains me to say it, I have to agree that maybe this isn't the right car for you :-(

Your previous E34 M5 being cheap to run (comparably) doesn't mean that they all are cheap to run.

It comes down to the option of
1 - paying a lot for one which has been extensively maintained (preventative or restoration bills)
2 - buying one on the cheap and then paying out to fix it

ether way these are not a cheap car to own, especially if you want to regularly use the performance and stay alive / on the road....

oil change every 3k
tyres every 5 - 8k
valve clearances at least every 12 months
some new engine parts EVERY year
work on the suspension / steering / alignment
and rust will be there somewhere, sills, jacking points, arches, footwell's
etc etc etc

these cars aren't modern disposable 12k - 15k low cost service vehicles.

and, IMHO, thinking that a car you buy will be reliable just because it's a BMW is going to wrong foot you... just like my 75 year old father though a classic ferrari he bought would be a pleasure to drive because it was a ferrari... he did 100 miles in it and then sold it. It was a great car*, but, it wasn't right for him and his age.
*(7600 miles in 25 years and a museum piece that had been cosseted all it's life, literally he bought it from a german car museum)
 
1 - 20 of 93 Posts
Top