Main Seals Noise

Chris1337 · 04-13-2019, 03:21 PM

Got the dolphin noise when coming to a stop, confident it is one or both of the main seals. is there any way I can figure out which one it is?

Welcome to NBA Jam · 04-13-2019, 05:51 PM

A mechanic's stethoscope would be one way. If you hear it loudly in the front, you'll know.

If it can only be produced when coming to a stop, have a second person drive the car and leave the hood open. Have them stop in front of you. You should be able to hear where it's coming from pretty clearly.

weehe126 · 04-14-2019, 12:59 AM

Seals don't just make noise. You have excess crankcase vacuum most likely from a bad PCV valve in the VC.

Chris1337 · 04-14-2019, 04:39 PM

Quote:

Originally Posted by weehe126

Seals don't just make noise. You have excess crankcase vacuum most likely from a bad PCV valve in the VC.

just changed valve cover and gasket, nothing else would make the noise besides main seals

weehe126 · 04-14-2019, 09:44 PM

In that case you are right. Probably damaged it/them from the bad PCV. My money is on front seal.

Turbod · 04-14-2019, 11:37 PM

Dolphin noise isn't DV or compressor surge?

Chris1337 · 04-15-2019, 01:58 PM

Quote:

Originally Posted by Turbod

Dolphin noise isn't DV or compressor surge?

No, it's a different sound. Going to change valve cover again and see if maybe the first was faulty. just did a smoke test and only smoke was from turbo seal for the intake

Chris1337 · 04-15-2019, 01:59 PM

Quote:

Originally Posted by weehe126

In that case you are right. Probably damaged it/them from the bad PCV. My money is on front seal.

Why the front and not the rear? That is my main question right now and a smoke test didn't show any leaks from either one

Chris1337 · 04-15-2019, 02:34 PM

Quote:

Originally Posted by Chris1337

Quote:

Originally Posted by weehe126

In that case you are right. Probably damaged it/them from the bad PCV. My money is on front seal.

Why the front and not the rear? That is my main question right now and a smoke test didn't show any leaks from either one

this is the noise I'm hearing

vteec · 01-11-2021, 03:54 AM

i have exactly the same noise.
any pointers please?

alex-t9 · 01-18-2021, 12:00 AM

Quote:

Originally Posted by Chris1337

Quote:

Originally Posted by Chris1337

Quote:

Originally Posted by weehe126

In that case you are right. Probably damaged it/them from the bad PCV. My money is on front seal.

Why the front and not the rear? That is my main question right now and a smoke test didn't show any leaks from either one

this is the noise I'm hearing

I had this exact noise a month or so ago. At first I thought it was bad pcv valve but soon after noise first came up, I started having issues with valvetronic. Valvetronic disabled and was throwing some malfunction codes. I re-flashed my MHD tune a few times and the noise and valvetronic issues have been gone since. Strangely though, I think I have a new oil leak in the rear engine bay; I can smell burnt oil after the car has been driven for 30+ minutes.

turducken54 · 01-18-2021, 12:18 PM

It's your valve cover. Chances are your seals are just fine and will not leak after fixing the true issue which is the PCV.

04-13-2019, 03:21 PM	#1
Chris1337 First Lieutenant 27 Rep 290 Posts Drives: 2012 e92 335i Join Date: Apr 2017 Location: Miami, FL iTrader: (0)	Main Seals Noise Got the dolphin noise when coming to a stop, confident it is one or both of the main seals. is there any way I can figure out which one it is?
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04-13-2019, 05:51 PM	#2
Welcome to NBA Jam Is it the shoes!? 3884 Rep 5,112 Posts Drives: (Sold) 2011 E92 335i ZMP 6MT Join Date: Mar 2014 Location: USA iTrader: (1)	A mechanic's stethoscope would be one way. If you hear it loudly in the front, you'll know. If it can only be produced when coming to a stop, have a second person drive the car and leave the hood open. Have them stop in front of you. You should be able to hear where it's coming from pretty clearly.
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04-14-2019, 12:59 AM	#3
weehe126 Brigadier General 1161 Rep 3,185 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	Seals don't just make noise. You have excess crankcase vacuum most likely from a bad PCV valve in the VC.
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04-14-2019, 09:44 PM	#5
weehe126 Brigadier General 1161 Rep 3,185 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	In that case you are right. Probably damaged it/them from the bad PCV. My money is on front seal.
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04-14-2019, 11:37 PM	#6
Turbod Major 396 Rep 1,210 Posts Drives: 2014 E84 X1 35i M Sport Join Date: Mar 2015 Location: Oregon iTrader: (0)	Dolphin noise isn't DV or compressor surge? __________________ 2011 E92 335i \| 11.7@125 SOLD 2017 Camaro SS \| 12.7@114 SOLD 2019 Audi TT RS \| 10.5@130 SOLD 2020 F97 X3M \| 11.0@123 2023 G80 M3 xDrive
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01-11-2021, 03:54 AM	#10
vteec Enlisted Member 6 Rep 37 Posts Drives: BMW Join Date: Feb 2009 Location: Malta iTrader: (0)	i have exactly the same noise. any pointers please?
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01-18-2021, 12:18 PM	#12
turducken54 New Member 8 Rep 14 Posts Drives: 2008 e92 335i Join Date: Jan 2021 Location: Dallas, Tx iTrader: (0)	It's your valve cover. Chances are your seals are just fine and will not leak after fixing the true issue which is the PCV.
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