Exhaust manifold gasket leaking Topic is solved

Rvolvos · Post by **Rvolvos** » 06 Jun 2020, 23:07

Our 2006 V70 153k miles is making a whistling sound, the sound is worse with a cold engine. But lately more pronounced. This was present when a bought the car, did not notice it when buying 3 years ago. Engine was warm when I test drove the car.
Could never find the issue, replaced all inter cooling Piping without a solution.
Today I replaced the intake pipe with a used SNABB one and while I was underneath the car and noticed black soothe near the gasket on cylinder 1 at the end of the manifold underneath.
With the engine running I can smell exhaust fumes coming underneath the heath shield.

My question is can I retighten the manifold nuts to 25 Nm? Or is there a risk of cracking the manifold.
Thanks!

Post by **abscate** » 07 Jun 2020, 05:18

Ease them off if loose, add some anti seize, andretighten.

If they won’t move and there is no leak, leave them alone.

Post by **vtl** » 07 Jun 2020, 06:37

Manifold is warped. Ports for 1 and 5 cylinder are bolted to the block with 1 stud/nut only, typically they warp over time and start to leak:

Straight edge on the manifold:

Also for some reason 4th cylinder develops cracks and fractures in gasket, seen that in two engines.

You do not want to re-tighten old studs, they may break, plus it would give very little in return, since the manifold is made of steel and it is warped. Needs resurfacing. Best course would be replacing all gaskets along with the studs and nuts.

Post by **oragex** » 07 Jun 2020, 06:51

Interesting about the manifold gasket issue. I wonder if same happens on non turbo ? Perhaps less likely given less hot/pressure/stress.

On the other side, the exhaust downpipe flexible on my non turbo may be weaker than the turbo one, mine started leaking around 120K miles. I also had a leak at the flange after the catalytic converter, on the converter side. Basically had to replace the flex-cat segment.

Post by **vtl** » 07 Jun 2020, 06:57

My DP had cracks in steel section after flex:

This was around 230k miles.

Rvolvos · Post by **Rvolvos** » 07 Jun 2020, 10:28

vtl wrote: ↑07 Jun 2020, 06:37 Manifold is warped. Ports for 1 and 5 cylinder are bolted to the block with 1 stud/nut only, typically they warp over time and start to leak:

Straight edge on the manifold:

Also for some reason 4th cylinder develops cracks and fractures in gasket, seen that in two engines.

You do not want to re-tighten old studs, they may break, plus it would give very little in return, since the manifold is made of steel and it is warped. Needs resurfacing. Best course would be replacing all gaskets along with the studs and nuts.

Thanks much for your detailed response. The soothe build up near cilinder 1 looks like your manifold.
Forgot to mention the whistling sound occurs with a warm engine too lately.

The cilinder head should be okay then and only the manifold needs resurfacing? From what I read this is not a small job removing the manifold.

Stuff is breaking faster on these cars than I can fix....

Post by **vtl** » 07 Jun 2020, 18:00

Rvolvos wrote: ↑07 Jun 2020, 10:28The cilinder head should be okay then and only the manifold needs resurfacing? From what I read this is not a small job removing the manifold.

Yes, only manifold. You can also just put a new set of gaskets and studs+nuts, they will buy you for some time to source a donor manifold and resurface it. This is what I did

Removing the manifold is not that difficult. Some nuts can be a pain though.

Rvolvos wrote: ↑07 Jun 2020, 10:28 Stuff is breaking faster on these cars than I can fix....

I finally got to a phase when it seems everything is fixed and not breaking

Unfortunately, there's no a car to replace our P2 wagons

Rvolvos · Post by **Rvolvos** » 07 Jun 2020, 20:50

vtl wrote: ↑07 Jun 2020, 18:00
Rvolvos wrote: ↑07 Jun 2020, 10:28The cilinder head should be okay then and only the manifold needs resurfacing? From what I read this is not a small job removing the manifold.
Yes, only manifold. You can also just put a new set of gaskets and studs+nuts, they will buy you for some time to source a donor manifold and resurface it. This is what I did

Removing the manifold is not that difficult. Some nuts can be a pain though.

Rvolvos wrote: ↑07 Jun 2020, 10:28 Stuff is breaking faster on these cars than I can fix....
I finally got to a phase when it seems everything is fixed and not breaking

Unfortunately, there's no a car to replace our P2 wagons

Thanks much, sourcing a replacement manifold sounds like a smart idea and have that ready to go.

I removed the heat shield to check out the exhaust manifold nuts. 6 of them were loose.

Near cilinder 1,2 and 3. I have hand tightened / use my wrist to torque them in a couple of steps, going back and forth. Took it for a test drive much better, less noise. I am going to check the Exhaust manifold nuts again tomorrow after the engine is cooled down and try to smell if there are exhaust fumes at start up.
Maybe I can defer this Repair and start working on fixing the power steering leak and leaking oil pan.

+ 1 on the P2 wagons.

Post by **abscate** » 08 Jun 2020, 04:59

I’ve got some old exhaust manifold gaskets if you want to try sneak another one in there

Tested exhaust gasket $5
Shop supplies. $25
Free used oil.

Seriously, I can mail you in an envelope

Rvolvos · Post by **Rvolvos** » 08 Jun 2020, 22:40

abscate wrote: ↑08 Jun 2020, 04:59 I’ve got some old exhaust manifold gaskets if you want to try sneak another one in there

Tested exhaust gasket $5
Shop supplies. $25
Free used oil.

Seriously, I can mail you in an envelope

Thank you very much for the offer, I will reach out to you if I cannot fix it by retightening the nuts.