[fastboatster]

Originally Posted by crashoverride

Valve stem seal failure is such a rarity on this engine. Not that anything and everything can break but this isn't a common failure for this engine.

Obviously a repair this big the expense is more than the car is valued... and for many of us here it's worth the expense. But it's not worth fixing such a rarity should it not solve the problem.

It would be well worth the diagnosis cost to take it to your dealership and have them professionally explore the many different causes and properly diagnose.

Yeah, at his mileage (200+) the actual “repair” is to get a lower mile e90, and just send this car to a salvage yard

[ptpending]

Originally Posted by crashoverride

Valve stem seal failure is such a rarity on this engine. Not that anything and everything can break but this isn't a common failure for this engine.

Obviously a repair this big the expense is more than the car is valued... and for many of us here it's worth the expense. But it's not worth fixing such a rarity should it not solve the problem.

It would be well worth the diagnosis cost to take it to your dealership and have them professionally explore the many different causes and properly diagnose.

valve seals are not failing, they are made from thermoresin, and due high temperature became like plastic, and lose their capability to absorb oil and return it to oil circuits. due that reason healthy engine begin to "eat" up to 1 liter oil per 1000 kms of the distance. and valve steam seal replacement fix that issue

[gT-BMW]

Hey e90, just wanted to share my experience hunting for a replacement long block.

Just as i thought. trying to find an engine replacement has been a total nightmare.

My local junyards take carry n52 bmw engines are 2 hours from me.

I've checked facebook marketplace as engines advertise as low mileage well maintained turns out to be complete piles of junk. one of them had a broken exhaust camshaft.

This one junkyard in tampa i visted advertised 3 n52 in stock. 30 day warranty. got there 2 of them seemed to have been left out in the rain or underwater pulled from a flood vehicle.

The other one was a n51 with the spark plugs pulled out. Not buying an engine if the orginal spark plugs are not in it.

It was missing the intake manifold. The "inventory specialist" told me its the same as the n52. i told him no the n51 has a lower compression ratio they added the 3stage to make up the power difference. begins to argue with me that he been doing this for years.

The last draw came i made the 2 hr trip again to tampa to check this engine:

https://www.ebay.com/itm/29584215779...Bk9SR9KXsrHGYg

got there and they were nice they let me check the motor with my camera, found that it has the same issue as my engine but dialed down.

Otheres wanted to have me leave a deposit on an engine that was still in the car but didnt run cause they sold the CAS.

Told them they have to remove the motor.

They said yes after a deposit.

This is bullshit. But anyways here is a shot in the dark. anybody in central florida area know of a good n52 that i can check out?

Originally Posted by crashoverride

Valve stem seal failure is such a rarity on this engine. Not that anything and everything can break but this isn't a common failure for this engine.

Obviously a repair this big the expense is more than the car is valued... and for many of us here it's worth the expense. But it's not worth fixing such a rarity should it not solve the problem.

It would be well worth the diagnosis cost to take it to your dealership and have them professionally explore the many different causes and properly diagnose.

Take my car to the dealership? This is a technical forum so we can avoid going to the dealership lol

Originally Posted by fastboatster

Yeah, at his mileage (200+) the actual “repair” is to get a lower mile e90, and just send this car to a salvage yard

I might have to count my losses and consider this option. I just spent $800 refreshed the suspension too

Originally Posted by ptpending

valve seals are not failing, they are made from thermoresin, and due high temperature became like plastic, and lose their capability to absorb oil and return it to oil circuits. due that reason healthy engine begin to "eat" up to 1 liter oil per 1000 kms of the distance. and valve steam seal replacement fix that issue

say what now

[ptpending]

Originally Posted by gT-BMW

say what now

valve seals are not failing, they are made from thermoplastic rubber, and due high temperature polymerize to solid plastic state,
and lose their capability to absorb oil and return it to oil circuits.
due that reason healthy engine begin to "eat" up to 1 liter oil per 1000 kms of the distance.
valve steam seal replacement fix that issue

[NZE90]

Just an idea and not sure if this is possible in the US, but over here we have damaged vehicle auctions where you can buy written of cars. A write off 330i goes for around $1000. Is this a possibility for you?

[ianoob]

I had similar issues with oil consumption and replaced my valve stems last summer. I tried to do this without removing the head, but the rear seals are impossible to get a spring compressor on. Also, the valve tools I tried (rope and air) both rotated my engine losing TDC.
Removing the head is fairly easy, just know that you cannot reuse ANY of the bolts.
For the eccentric shaft springs, do NOT remove the bolt on top. Instead, use a hook or rope to pull the arm away from the retainer. When reattaching, double check that they are seated properly. I intend to do MILVS this fall, so I can take photos then.
The head gasket is specially coated, don't scratch it or you could get galvanic welding.
Changing the seats helped, but did not completely fix my oil consumption. I ended up using Engine Restore as well, just note that you need to clean the VANOS filters first and introduce the additive over multiple trips.
Good luck!

[Saico]

ianoob, what is the improvement in oil consumption that you recorded after changing seals?

[gT-BMW]

Hey e90 just wanted to update this thread and finally close it out.

I was about to give up, as i couldn't believe how hard it was to find a decent engine, so i was about to call the scrap guy to take this car, but something in my mind told me to check fb marketplace one last time.

As luck would have it, a brand new listing for a n52 engine came up. Skeptical of the listing and since it was only a 40 minute drive instead of 2 hours, I've decided to check it out.

When i got there, i saw 2007 328i 6speed manual that was obliterated from the rear with an empty engine bay. It had 128k.

The guy showed me of the video of it running before he pulled it out. He also let me check spark plugs. Finally a clean burning engine! This is the one Ive been looking for!! He took 800 cash and off i went with it!

I started ordering parts from fcp euro, new valve cover ,oil pan gasket, ofh, water pump & thermostat, lower rad hose, intake mani gasket, coolant, oil, 02 sensors, etc.

I wanted to keep the magnesium valve cover with the external ccv, so i had to swap over the old oil pan.

All in, i've spend around $1650 and now its running again. I've put 1600 miles on it so far, doesnt burn a drop of oil. Mission accomplished.

I just wanted to thank everybody on this thread that steered me in the right direction as i was about to make a costly mistake.

I love this forum, i learned so much from you guys. Thanks to the valuable info and people on this forum, my car is ripping again!

[NZE90]

Nice work! Are you planning to disassemble the old engine or just dumping it? Would be interesting to know what the cause was.

[gT-BMW]

Originally Posted by NZE90

Nice work! Are you planning to disassemble the old engine or just dumping it? Would be interesting to know what the cause was.

Thats a good question. Cause i don't know what to do with the old motor. I can disassemble it, but what should i look for?

I just want to disclose that i purchased this car at 134k miles 6-7 years ago with it finally accepting it burns oil as normal (which is not), but i still modded it anyways and after years of use it got considerably worse. I even ran 14.3 in the quarter mile with it like this, burning oil.

Not the fastest thing in the world, but it continues to raise my blood pressure in a way that its enjoyable every time i drive it, that's why i keep putting oil in it, i cant explain it. maybe im insane. but it is the reason why i wanted to save it.

also if it wasnt for this forum, i would have not known i can mod this car like this, stock, and enjoy it it this much.

[gunnerxq]

Originally Posted by ianoob

I had similar issues with oil consumption and replaced my valve stems last summer. I tried to do this without removing the head, but the rear seals are impossible to get a spring compressor on. Also, the valve tools I tried (rope and air) both rotated my engine losing TDC.
Removing the head is fairly easy, just know that you cannot reuse ANY of the bolts.
For the eccentric shaft springs, do NOT remove the bolt on top. Instead, use a hook or rope to pull the arm away from the retainer. When reattaching, double check that they are seated properly. I intend to do MILVS this fall, so I can take photos then.
The head gasket is specially coated, don't scratch it or you could get galvanic welding.
Changing the seats helped, but did not completely fix my oil consumption. I ended up using Engine Restore as well, just note that you need to clean the VANOS filters first and introduce the additive over multiple trips.
Good luck!

How exactly did you manage to get Engine Restore to work in your engine? It's the only oil additive that would make the engine shake violently until I changed out thd oil.

Attempted this 3 times over the years with the same results.