Developed ticking on my 95 740iL

I used Rotella 15w-40 Synthetic Diesel oil at the last oil change to see if it'll help with the excessive oil consumption. I don't think anything will help due to it being a Nikasil block. I'll switch back to Castrol Syntec 0w-30 or Mobil 1 0w40 at the next oil change to see if it'll like me again. Maybe it didn't like the drastic change...

Category:

Autos & Vehicles

Tags:

• BMW
• E38
• 740iL
• 750iL
• Castrol
• Mobil1
• Rotella

[forgewire]

I had the similar sound in 328ci caused by a loose spark plug.

Dealers wanted to charge me ~500 euro just for the injection and compression tests. When brought to another garage (their mechanic used to work for BMW) he said straight away that it could be a spark. He tighten it up and the knock has gone. I'm using Castrol Edge Sport only

[visionbmw]

@forgewire The M60 and M62's tend to have plugs that back out. I haven't experienced it in an M50 or M52. That was the first thing I checked, but they were all tight. It was the Diesel Synthetic oil I tried. The M62 didn't agree with it. When I switched back to Mobil 1 or Syntec, it went away.

[jayguy173]

Ticking is caused by bad lifters if you dont have solid rockers.

[visionbmw]

From what I was informed, Diesel oil shouldn't be used in BMW gasoline engines because of the different characteristics in the oils. Since then, I've used regular dino oil, and the ticking never came back. This car is now owned by my former neighbor, and there are no problems with ticking. Still consumes oil, but that's because it's a Nikasil block with 192k on it.

[jayguy173]

Oil burning is caused by valve stem seal guides or the piston rings being warn or stocking using a thicker oil will only cause preformance loss and maybe slow it down.

[visionbmw]

BMW NA replaced these failed Nikasil engines with an Alusil block. There are still a lot of Nikasil engines out there, but because gasoline no longer has high Sulphur content, the Nikasil engines that have lasted >100k may have not been affected by the regions with high Sulphur content back then, which is no cause for concern anymore.

[KB3MMX]

Diesel&Gas dual rated oil is fine as long as it is RATED PROPERLY (SJ, etc..) for the GAS engine you're using it in. Actually the Dual rated oils will provide far more protection than gas only oils. The reason for this i because the Diesel engine must survive a much dirtier oil than a gas engine. Any oil must be properly rated for the engine in which it is used !!

[jayguy173]

ticking is normal until the oil warms up however some oils will be better yes

[visionbmw]

Typically, yes. But, if you're not familiar with BMW engines, BMW had certain years in the V8's where the cylinder walls were lined with Nikasil. During that time, there was high Sulphur content in gasoline which reacted with the Nikasil thus creating wear at the top of the walls. Due to this "self-destructing deterioration", sometimes the engine would fail to start. This was also a factor of oil consumption. This was even found in engines with less than 30k miles.

[kebabtank]

Yes, this could be a symptom of nikasil lining wear in the engine block due to poor quality, or high sulphur fuels. The main symptom is rough idling, as you've shown. Just a thought.