Exhaust leak?

[pt1965]

2010 z71 suburban 5.3 174k
ive had this rig 1 year and have had exhaust leak repaired on drivers side at the donut, now it seems the passenger side. without taking to shop, how do you confirm that its an exhaust leak? and how to pinpoint the location? i get the ticking noise when its cold but it goes away once the it warms up, i guess due to expansion?

 

[kbuskill]

On motorcycles I use a BBQ grill lighter to check for leaks.

Start the bike and hold the open flame around the gaskets to see if it gets blown out.

Would probably work on your truck too.

Mechanics stethoscope would work too.

 

[Bob2C]

I have used soapy water in spray bottle. Just do it when the exhaust is cold in the first few min of starting. If you have a leak it will bubble. Mix some dish soap with water.

 

[OR VietVet]

You can get a bunch of rags and while the engine is at idle hold the rags over the end of the tailpipe and block the flow. The back pressure will blow out at the leak and a good set of ears or mechanic's stethoscope will find it. Did you check for any broken exhaust manifold studs?

 

[Bob2C]

I also saw a YouTube video of someone using a shop vac with reversed air. Inserting in pipe, sealing with tape listening and feeling. Many options available.

 

[pt1965]

You can get a bunch of rags and while the engine is at idle hold the rags over the end of the tailpipe and block the flow. The back pressure will blow out at the leak and a good set of ears or mechanic's stethoscope will find it. Did you check for any broken exhaust manifold studs?

not yet, thanks for the tip!

 

[pt1965]

I have used soapy water in spray bottle. Just do it when the exhaust is cold in the first few min of starting. If you have a leak it will bubble. Mix some dish soap with water.

i will try that, thanks for the tip!

 

[pt1965]

update! dealer said i had multiple leaks on both sides, they replaced both manifolds but couldnt extract rear bolts on both sides. really? this doesnt see right! see attached pic of invoice.

 

[kbuskill]

update! dealer said i had multiple leaks on both sides, they replaced both manifolds but couldnt extract rear bolts on both sides. really? this doesnt see right! see attached pic of invoice.

View attachment 249570

Wow, good thing you took it to the dealer to make sure it was fixed properly. It probably won't leak for at least a month or two.

I can't imagine paying $1100 for an incomplete repair. That is absolutely ridiculous.

I guess they didn't have a welder and a couple of nuts to spare to get the other two broken studs out of the heads?

 

[OR VietVet]

Did they give any warnings, before or during the work, that they could not get to the rear broken studs and if they were replacing them the price would be higher because of removing heads?