Smoke test to identify exhaust leak (ticking sound)

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I built a simple pressurized smoke testing device to identify exhaust leak (s). My plan is to use 4th of July smoke bombs. I'm a bit concerned with coating o2 sensors & cats with whatever may come out of these 4th July type smoke bombs. I'd really like to hear the forums thoughts and experience with this.

Has anyone tried this?
Are these smoke bombs ok to use?
Is there a better or safer smoke sources, readily available or producible with household stuff?

Edit: Used food grade Mineral oil and re designed smoke box (see last three pictures)


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Edited with updated smoker, I should get less leaks and high pressure.
Smoke machine 2 (1).JPG

Smoke machine 2 (2).JPG
Smoke machine 2 (3).JPG
 
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The O2 Sensors could be removed and left dangling to prevent any contamination. Cover the holes with duct tape or something.
Another option is to use Sea Foam treatment on your engine through the pcv hose. Makes a LOT of smoke on most vehicles, and is labeled as safe for O2 sensors. Lot's of info here on 'Mud on how to best use this. It makes so much smoke that it draws attention. I have since tried to use it at night, and then go on a late night drive to burn it off while most everyone else is asleep. Should be plenty effective for your leak identification purposes if the smoke bomb doesn't do the trick.
 
The O2 Sensors could be removed and left dangling to prevent any contamination. Cover the holes with duct tape or something.
Another option is to use Sea Foam treatment on your engine through the pcv hose. Makes a LOT of smoke on most vehicles, and is labeled as safe for O2 sensors. Lot's of info here on 'Mud on how to best use this. It makes so much smoke that it draws attention. I have since tried to use it at night, and then go on a late night drive to burn it off while most everyone else is asleep. Should be plenty effective for your leak identification purposes if the smoke bomb doesn't do the trick.
Good idea to removed but is it necessary?
Then there is the cats which can't be removed.

I've used sea foam and did not find or see anything.

Here's a clue: It's your manifolds that are ticking. Unless you are planning to repair them with a welder, just replace them with DT headers. No smoke required.
May be it is, but manifold was Lexus Dealer replaced. Slee tells me they've never seen a replacement go bad (leak). I'd like to verify manifold leak if that is even what I'm hearing, before throwing parts at it.

I did find some info (not verified) on what make the different colors of smoke:
Chemicals Used to Color Flames
  1. Red - strontium salts, most easily found in road flares
  2. Orange - calcium chloride (laundry bleaching agent)
  3. Yellow - sodium nitrate (common in chemistry lab)
  4. Green - barium salts, such as barium nitrate (common in chemistry lab)
  5. Greenish-Blue - copper sulfate (common in a chemistry lab, also found in many algicides for pool treatment) Blue - copper chloride (common in chemistry lab)
  6. Purple - potassium permanganate (common in a chemistry lab, also used in sewage or water treatment)
  7. White - magnesium sulfate (epsom salts, found on laundry aisle or in a pharmacy)
Also:
Color Compound
Red: strontium salts, lithium salts
lithium carbonate, Li2CO3 = red
strontium carbonate, SrCO3 = bright red
Orange calcium salts
calcium chloride, CaCl2
calcium sulfate, CaSO4·xH2O, where x = 0,2,3,5
Gold incandescence of iron (with carbon), charcoal, or lampblack
Yellow sodium compounds
sodium nitrate, NaNO3
cryolite, Na3AlF6
Electric White white-hot metal, such as magnesium or aluminum
barium oxide, BaO
Green barium compounds + chlorine producer
barium chloride, BaCl+ = bright green
Blue copper compounds + chlorine producer
copper acetoarsenite (Paris Green), Cu3As2O3Cu(C2H3O2)2 = blue
copper (I) chloride, CuCl = turquoise blue
Purple mixture of strontium (red) and copper (blue) compounds
Silver burning aluminum, titanium, or magnesium powder or flakes
 
Have you already tried the shop-vac/incense stick trick to see if smoke gets pulled in?
 
Have you already tried the shop-vac/incense stick trick to see if smoke gets pulled in?
I've not tried that, worth a shot I suppose. The biggest problem will be how difficult it is to get to most parts of the manifold. Most areas of it are not accessible.
 
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Were both manifolds repalced, or only one side?
VIN indicates only DS was done. If I'm reading the notes correctly, what do you think: "REPLACED CRACKED L/F EXHAUST MANIFOLD, GASKET AND STUDS AND BOLTS"
I hear the sound when putting my ear up to DS wheel well, but not PS.
 
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I would read that as a typo and it most likely was supposed to say replaced cracked L/R manifold.

Either way, good luck on your search for proof of where it's leaking.
 
I would read that as a typo and it most likely was supposed to say replaced cracked L/R manifold.

Either way, good luck on your search for proof of where it's leaking.
That's what I'm thinking (L/R) now that you pointed it out, and thanks.

There's some good tips in this PM article that you can use before you try smoke

How to Find a Vacuum Leak
Thanks, I've read a number of acticals and would love the Redline's Smoke Pro. But starting at $750 is not cost effective in DIY job.



It took me about 2 minute $0.00 using stuff lying around to make my device. The idea of using smoke bombs, well it the 4th and they can be found on every corner for next few weeks. The colors like red or blue would make spotting a leak easy. But last thing I want to deal with is fouled o2's a & cats.

What are some other ways of producing smoke that is safe?
 
In looking up the redline oil for their smoke pro I found this statement:
"OEM-Approved Vapor Producing Fluid designed specifically for automotive diagnostic machines.
One 8 fl. oz. (29.6 ml) bottle can service over 1000 vehicles!
Mineral Oil USP or NF, white medicinal or Food Grade Type H1.
Part No. 96-0039" OEM-Approved Vapor Producing Fluid

I'll just put some hot coals in a can and pour some mineral oil over them. Not as fun as smoke bombs, but could be interesting.
 
Good find, hmmm basic mineral oil. Thinking out of the box, wonder if you can rig a vape pen to stay switched on- or hook a small vacuum hose to it. That would surely give you a steady stream of vaporized smoke in a small easy to use size.

Fwiw The MSDS here under Napa's private label version by redline,which looks to be sourced from Chevron.
http://s7d9.scene7.com/is/content/GenuinePartsCompany/1822004pdf?$PDF$
 
Good find, hmmm basic mineral oil. Thinking out of the box, wonder if you can rig a vape pen to stay switched on- or hook a small vacuum hose to it. That would surely give you a steady stream of vaporized smoke in a small easy to use size.

Fwiw The MSDS here under Napa's private label version by redline,which looks to be sourced from Chevron.
http://s7d9.scene7.com/is/content/GenuinePartsCompany/1822004pdf?$PDF$

Do vape pens' put out a lot of smoke?
Thanks for the link.

I'd like to produce a great deal of smoke over 5 minutes or so, to give me time to inspect exhaust end to end. I'd hoped someone had a good handle on use of colored smoke bombs which would give extra visibility. But I suppose not worth the risk for me to venture into unknown effects on o2s & cats.

I could try sea foam again through intake. This time partially blocking the tail pipe with something. But this means running the engine at operating temp. Manifold exhaust leaks are most apparent when exhaust is cold, and working around hot exhaust systems is no fun. So not a preferred method. Although Sea foam may work as a medium in my device, I may give it a try.

I'd also think any low temp vegetable & animal based oil would burn off the o2's & cats, with a few 5 minute high RPM runs on the highway. Kind of like turning on the self cleaning feature of an oven, turns organics into dry ash.

So my list of possible mediums for use in my device, are in order of safest first:
Redline or NAPA smoker oil (Mineral oil (food grade)).
Sea foam.
Tabaco.
White HVAC inspection smoke bomb.
Vegetable oil.
Glycerin.
Some Colorado home grown could be interesting:smokin:

Any ideas other than hot coals for a heat sources?
 
If the real goal is to find the source of the ticking sound, then why not use a mechanic's stethoscope?
 

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