Re:Question about exhaust leak test

Hello im new here 
i have been reading the forums like a guest for a few days now and so far i have found many interesting posts 

seems like there is plenty of knowledgeable people here about car repairs 

i like to work on my own cars too but im just the classic backyard mechanic who needs to learn a lot

I decided to register here to ask for some information and hopefully also help when i can

Ok im currently working on a 2006 nissan titan 5.6 v8

I suspect an exhaust leak and i want to do a test that i saw in another post on these forums 

My plan is to use an leaf blower to introduce air into the tail pipe and then use the soapy water to find out leaks (if any) 

But theres some things i need to fully understand  before i do it 

Once i connect and turn on the leaf blower isn't that going to be too much pressure?

lets hypothetically say that i dont have any leak does the air pressure is going to blow any gaskets or something? 

Or maybe i need to make the connection on the tail pipe kind of loose so any pressure can escape trough there?
Thank you

I'm not sure a leaf blower will work very well for this I use a large shopvac , the shopvac uses a centrifugal fan which can build a small amount of pressure (not much maybe a couple psi) a leaf lower uses a blade type fan and cavitates when blocking the output (atleast mine does) so I don't think your going to be able to build any pressure to test for leaks. To answer the damaging gaskets part no it would take way more pressure than that to blow out a gasket or flex pipe . Maybe we could invent a shop airline tailpipe adapter for that?

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Like Ben said, it'll take quite a bit of pressure to actually damage anything during this test. Your leaf blower (or whatever you're using to adapt it) will likely pop out of the tailpipe long before you break anything.

The trick is to take care and only build a few PSI of pressure in the exhaust. 10 PSI at most. Much more than that, and your soapy water will reveal leaks that don't exist otherwise. Kinda like taking a cooling system pressure tester and dialing it up to 30 PSI. You're gonna make something leak. :lol:

Thank you guys for your reply

If i understand correctly what you are telling me is this:

do make an airtight connection at the exhaust tip
but have a way to measure the psi output going into the exhaust system
is that correct?

Theres videos out there using either a leaf blower or shop vac without an air regulator
What do you think about that?
Thank you

I'm totally fine with the shop vac and leaf blower setups. Measuring the pressure would be nice, but not required.

Most techs that I see doing it that way use shop rags to seal the shop vac to the inside of the tailpipe. That works well to keep most of the pressure in the exhaust, but vents some through the cloth as the pressure increases. If the pressure goes to high, the rags get blown out. That'd be my recommendation.

Thank you for the info
I'll try it out and see if i can find exhaust leaks