[TConover]

Hi. I just bought a 1998 740i that seemed to be in amazing condition. It ran smooth, sounded and looked great. The day after I bought it I noticed white smoke coming out of the tail pipe when I first started it.

Today on my way to the train station it blew a huge plume of white smoke for an 8th mile down the road on highway 35. So embarrassing.

How much will it cost to get fixed??? And advice or help??

Thanks

[Dackelone]

Originally Posted by TConover

Hi. I just bought a 1998 740i that seemed to be in amazing condition. It ran smooth, sounded and looked great. The day after I bought it I noticed white smoke coming out of the tail pipe when I first started it.

Today on my way to the train station it blew a huge plume of white smoke for an 8th mile down the road on highway 35. So embarrassing.

How much will it cost to get fixed??? And advice or help??

Thanks

White smoke on startup is a bad PVC(OSV) the membrane has a tear and is allowing oil to burn off on cold start.

To test IF your headgasket is bad... go to a shop with a CO2 meter... and have the exhaust sniffer help on top of your open radiator cap... IF it detects CO2, then your HG is shot. But I really think its your PVC valve - his is a common problem on these V8's.

[Wolf 335]

As Dackelone mentioned OSV (Oil Separator Valve) membrane has a tear and oil is entering through it and burning.

Very common problem on M62 engines.

Had a same issue on my e39 540i (same engine as your 740i). Repair is a bit complicated due to the its location at the back of the motor. You are replacing the part pretty much blind folded. Good to take it to a mechanic that has done a few of these jobs.

This is what's happening at the back of your intake manifold.





Photos taken from: http://home.comcast.net/~vicent/osve38.html

You can go to this site for DIY instructions.

*in addition to this engine and its common issues, inspect your engine mounts as they wear from the v8's high torque. Worn out mounts will cause engine to shift under load and yank on the cooling components and potentially causing an issue (I think mainly the lower coolant hose). Have your rear main seal checked for leaks and drive shaft hanger bearing for wear (when it gets really bad you'll start hearing clunking noises under your armrest).
Also I don't want to scare you but there have been cases where the timing chain rail guides where cracking and causing some major problems for some poor souls. Ill let you research that so you can understand the seriousness of this issue and complexity of that repair.

Hope this helps.

Cheers!

[TConover]

Originally Posted by Wolf 335

As Dackelone mentioned OSV (Oil Separator Valve) membrane has a tear and oil is entering through it and burning.

Very common problem on M62 engines.

Had a same issue on my e39 540i (same engine as your 740i). Repair is a bit complicated due to the its location at the back of the motor. You are replacing the part pretty much blind folded. Good to take it to a mechanic that has done a few of there jobs.

This is what's happening at the back of your intake manifold.

Attachment 1305135

Attachment 1305136

Photos taken from: http://home.comcast.net/~vicent/osve38.html

You can go to this site for DIY instructions.

*in addition to this engine and its common issues, inspect your engine mounts as they wear from the v8's high torque. Worn out mounts will cause engine to shift under load and yank on the cooling components and potentially causing an issue (I think mainly the lower coolant hose). Have your rear main seal checked for leaks and drive shaft hanger bearing for wear (when it gets really bad you'll start hearing clunking noises under your armrest).
Also I don't want to scare you but there have been cases where the timing chain rail guides where cracking and causing some major problems for some poor souls. Ill let you research that so you can understand the seriousness of this issue and complexity of that repair.

Hope this helps.

Cheers!

Thanks so much for your help guys! I'm going to the mechanic today. I'll keep you updated on what happened.

Trying to stay positive.

[TConover]

I just talked to a Bmw specialist and he thinks it's the backing plate or osv as well. So happy it's not a head gasket!

Thanks for all your help guys. Really appreciate it!

[Wolf 335]

Enjoy the car. 740i was the first bmw i ever drove and instantly fell in love. True beast.

Did you do the exhaust mod? The amount of endorphins that get released in your brain once you start the V8 and hear the growl is unreal!

[m5james]

www.e38.org will be your best friend.

[Dackelone]

I have a '99 535iA e39 as my daily driver... its its been quite reliable. I bought it four years ago with 244K kms on it, now it has almost 439K kms. When I first bought it did break down on me twice... but it was for issues that the previous owner neglected. I pretty much did a thorough maintenance(Waterpump, belts, tuneup stuff, all fluids, brakes all around and new tires) ever since then... its never left me stranded. I really love this little 245Hp V8 3.5 liter engine. But what I really want is an Alpina B10S e39.

Dackel


my e39 beater...

[TConover]

Originally Posted by Wolf 335

Enjoy the car. 740i was the first bmw i ever drove and instantly fell in love. True beast.

Did you do the exhaust mod? The amount of endorphins that get released in your brain once you start the V8 and hear the growl is unreal!

No. I'll see what happens when it gets fixed. I'll put some nice toys in it down the road for sure. Just Wanna get it running perfect right now

[TConover]

Originally Posted by Dackelone

I have a '99 535iA e39 as my daily driver... its its been quite reliable. I bought it four years ago with 244K kms on it, now it has almost 439K kms. When I first bought it did break down on me twice... but it was for issues that the previous owner neglected. I pretty much did a thorough maintenance(Waterpump, belts, tuneup stuff, all fluids, brakes all around and new tires) ever since then... its never left me stranded. I really love this little 245Hp V8 3.5 liter engine. But what I really want is an Alpina B10S e39.

Dackel


my e39 beater...
Attachment 1306433

Attachment 1306434

Great car man.

[GuidoK]

e39 535i is a v8 (m62)

http://bmwfans.info/parts-catalog/E3...browse/engine/

On the e34 and earlier models they were i6 (m30)

[TConover]

Good news! It is the OSV or backing plate. So I'm gonna do that and a water pump replacement she'll be running well by the end of the week!

Thanks for all your help everyone