Smoke generator for exhaust leak testing?

[wild man]

Would this be a feasible approach for checking to see if there are any leaks in the piping feeding the turbine, including the bypass (WG) section?

Also, are these devices generally available for a reasonable price, and where can they be found?

[Techno Duck]

Snap On for example does make an evap test machine that pumps an inert gas into the intake or exhaust tract that will come out of any leak you have on the car. They work very well and are probably one of the best diagnostic tools for finding intake or exhaust leaks. You can buy a 944 for the cost of the machine though.

I am lucky my buddy has one that i have used a number of times.. leaks show up like this



I have read about people using smoke machines used for partys and stuff like that but i would have concerns about what smoke is actually being pumped into the intake or exhaust tract. The Snap-On machine uses a oil based smoke that is inert.. not sure what those smoke machines put out but i would have concerns about condensation and leaving residue in the intake tract.

[badcoupe]

yeah I have the otc one and they are an invaluable tool but a little pricey. I think speedforce came up with one that used a cigarette then patented and sold it a few years back.

[wild man]

Originally Posted by badcoupe

yeah I have the otc one and they are an invaluable tool but a little pricey. I think speedforce came up with one that used a cigarette then patented and sold it a few years back.

Over-the-counter?

No, I suppose that's got to be a brand name. I tend to shy away from such items when "pricey" is one of the terms used to describe them.

But the SF idea has definitely got the gears turning. Although I haven't been a buyer/user of tobacco products since 1988, I'm sure that other "smoke producing" products would suffice perfectly well, albiet without the vaporizer. And who knows, the car might even LIKE it.

Seriously though, what the "gears" have churned up with, is a very simple device that would go in-line with a compressed air line. And as long as I don't try to find out ANY information on how the SF device works or what it looks like, they can't sue me for patent infringement, if what I build ends up being very similar, correct. I just don't think that there could be very many variations on that particular idea (pieces of pipe, screw-on fittings, internal "butt" holder, etc).

Thanks for the responses. You could say that I have now received my instructions from "above"!

[2001f4s]

Wild man, I am not sure of the wisdom of this recommendation, but it did work for me, and my car is still with me. I used an incense stick, along with the pressurized air approach I learned about here or on Rennlist. The incense stick is small enough to fit around most of the vacuum connections, and it smokes sufficiently to look for leaks. Ended up finding a hole in the J-Boot.

Plus my engine bay smells very fine now. :0

[wild man]

I think the incense approach is an excellent idea. Less costly, and probably far less less tarry than the other options. That's definitely the way I will roll. Thanks for the input.

[968 GUY]

Am I correct in thinking that the exh. pipe is blocked off and pressurizing the intake while the smoke is introduced?

[wild man]

No, that's not quite what I was thinking. Int and exh need to be done separately, with each one having it's own block-off and pressurized introduction of the smoke.

[968 GUY]

Yeah I have heard of testing like this, but not heard it described.
I think arnworx has a procedure written up for testing intake system.

[Techno Duck]

Originally Posted by 968 GUY

Yeah I have heard of testing like this, but not heard it described.
I think arnworx has a procedure written up for testing intake system.

Smoke testing the intake makes finding leaks alot easier but pressure testing works just as well. You just need to make a PVC fitting with something like a tire schrader valve on it that fits into one of the intercooler pipe couplers. You can test at the turbo inlet aswell if you wanted.

I hook up a spare boost gauge up to the intake manifold so i can easily monitor pressure. You usually dont need much more than 10psi or so to hear any leaks. I use a tire chuck to control how much air i am letting in but a regulator would work just as well.

This adapter is from Arnnworx, not sure if he still makes them but it works well. Just becareful when using something like this as its not totally impossible for it to blow out of the coupler.

[wild man]

Originally Posted by 968 GUY

Yeah I have heard of testing like this, but not heard it described.
I think arnworx has a procedure written up for testing intake system.

That's funny, because I must admit: Yeah, I have described testing like this, but not yet tried it. The description was fabricated out of pure intuition and common sense (like needing to block off the intake in order to pressure test it). That is a good post by techno duck. I do have something very similar to the ARN device, but it is made of plastic (nylon).

[2001f4s]

Here is where I found the description for Vacuum leaks and added the incense part:

YouTube - ‪DIY - how to pressurize your 944 turbo intake system‬‏