[cybergio]

Hello guys,

I have 2008 BMW 535i with N54 engine, manual transmission. When the previous owner detected an extreme white smoke coming out of the car’s exhaust, he stopped driving and towed the car to his mechanic who diagnosed the head gasket failure, also misfire in the cylinder 2 and 5. Me and my friends bought the car expecting the head gasket to be blown, but after taking the engine apart and removing the engine block, we were confused by what we found inside, the head gasket seems to be intact. On the early stage of taking removing the engine we found a jelly like substance in the car’s coolant system. it seems like two different coolants were mixed together which formed white jelly like substance, clogging the system, but after examining the head gasket we don’t see any damage to it. So now we are confused, having hard time deciding which is the best, putting car back together with a new head gasket, cleaned coolant system and new injectors or we need some more advanced work done on the engine block and other parts.

P.S We also tested the water pump and it was in good working condition.

Please see the images attached below.

[JM98]

That jelly happens when someone mixes Dexcool (orange coolant) and traditional antifreeze (green coolant). Head gasket failures on these cars are super rare, and smoking turbos, cracked valve covers, or faulty PCV systems are often misdiagnosed as such. Did you perform a a leakdown and compression test before taking it apart?

[cybergio]

We didn’t perform those tests cause were convinced 99.99% that the head gasket was blown, that’s what they told the old owner at the dealership. Taking the engine apart was still a good thing, now we can clean it up properly from the jelly stuff.

[iqraceworks]

Wow....a simple compression and leakdown test would have saved you a lot of wasted hours......

The whole issue is/was probably a bad turbo seal, or an issue with the valve cover/pcv system getting oil into the intake.

[buglinjo]

There's also a possibility that white smoke was caused by bad injectors. When we drained oil it had a crazy smell of gasoline.

iqraceworks
Yeah, but it's a good thing, we will clean up that jelly in the block, replace old seals and O rings and carbon buildup. I think it was still worth it. We will replace turbos and injectors in the process of assembly. Hopefully, it will fix the issue, otherwise, there will be only one option left, PCV.

[iqraceworks]

Originally Posted by buglinjo

There's also a possibility that white smoke was caused by bad injectors. When we drained oil it had a crazy smell of gasoline.

iqraceworks
Yeah, but it's a good thing, we will clean up that jelly in the block, replace old seals and O rings and carbon buildup. I think it was still worth it. We will replace turbos and injectors in the process of assembly. Hopefully, it will fix the issue, otherwise, there will be only one option left, PCV.

Yeah....but you could have flushed the coolant system and cleaned it out that way ...pulling the motor is a ton of extra work. I guess at this point ..it doesn't matter.

Good luck with the rebuild 👍

[JM98]

Might as well do all the gaskets while you have the engine out, way easier to do (and super cheap).

[buglinjo]

Originally Posted by JM98

Might as well do all the gaskets while you have the engine out, way easier to do (and super cheap).

Yeah, that is our plan for now.

[JM98]

honestly, you guys are in a good spot. Do all the gaskets and button everything up and that car is good to go for years

[335iN54enthusiast]

Check out my channel and video for smoking N54s....Head gaskets are never an issue on these motors.

Side note...bad exhaust valve guides are common and a source of smoking.

[michael2bmws]

Damn. I wish I had 1 friend who knew how to take this engine out. I have an N52 that I suspect has a blown head gasket but am afraid to disconnect the AC condenser lines, keeping me from removing the front impact bar.

[alpnwss]

Does anyone know what the damage could be from mixing some (4 cups maybe) of the orange stuff with the blue stuff? I had my local shop top it up and just realized they mixed it.
I have since drained it after doing WP/Tstat. I feel like this should be a non-issue, but I've assumed wrong before. I have no cooling or running issues so far so, we'll see.

[mweisdorfer]

If you have the engine In that state, I'd :

1) VC
2) RMS
3) Megatronic Seal
4) Crank Seal
5) OPG
6) head gasket (of course)
7) OFHG

I'd do 1, 5, 7 by sandwiching an OEM gasket in between two beads of Ultra Black. You will absolutely prolong the life of those gaskets.

No.'s 2 & 4 use Ultra Grey. Stay away from the BMW sealant - it's not worth the headache.

In both cases above wait 24 hours before running the car so the Ultra Grey & Black can fully cure.

I'd also get a Bentley Repair manual so you know all the torque specs. You are working with a lot of Aluminum parts. So, that will be super important.

As far as the smoke, probably bad turbos & PCV valve system.

I'd encourage you to buy turbos from RB & his PCV system. Do that before you put the intake & VC on. At the very least, get a BMS catch can & upgraded PCV valve.


https://www.rbturbo.com

[_N54]

Also keep in mind its aluminum so if it did heat up pretty badly then you might want to have the head and surface of the block inspected.