DIY Smoke Leak Tester: How to

I've never had luck tracking down vacuum leaks but had Dave at Cryotune smoke my car one time and it was just awesome. I wanted to pick up the unit but there was not way I could justify the nearly $1000 price tag of a professional unit. After much research I decided to make my own. Then it seemed like others were interested in it and so I decided to go ahead and make a how to.

There are many ways to get it accomplished. The goal is just to vaporize mineral oil and have low pressure push it into the system. The main thing I found in my research was that you dont want it to exceed 2PSI to not blow EVAP seals. Some people just use soldering Irons but I felt like this was the best overall design even though it can be improved with a flow meter and a few other parts.

List of supplies used:

-Fish/pond air pump. I liked that the one I had was adjustable. Some people use a hand pump (I would get a foot pump) or use an adjustable propane regulator to lower pressure to 2PSI if using a compressor.

-Resistance wire/Vape wire. Every subie owner has a warehouse of this stuff because we're all vape bros . Any vape store will have some. I used 22g 316SS wrapped 12 times. I had read that 4amp was target - I used between 2-3amp and didnt play with it - I was happy with the output. I used two calculators to figure out what I needed for what gauge to hit my targets. Using Ohms Law you can use your voltage and target amps to get the ohms required (unless you know your target ohms, but I was aiming for 4amps). Using that info you can then use this calculator plus the gauge, type of wire, and diameter of your wick to determine the number of wraps to get your target.

-Food grade mineral oil. Theres additional dye you can add that provides a fluorescent color. Good for when you go to the raves.

- Aligator Clips

- Wire

- Inline Fuse

- Eyelet terminals

- Tiki Torch wick (any wicking material will work - cotton shirts even)

- Paint can

- 2" ABS end cap. This fit snug into my Perrin turbo inlet hose.

- Hose Barbs. 2x 1/4 HB to 1/8 NPT and 2 3/8 HB to 1/8 NPT.

- Lamp/Switch nuts. They're 1/8 or 1/4 IPS thread. work great on 1/8NPT

- Nuts, bolts, washers

- Grommets. Theses went into the paint can and keep the wire eyelets from touching the can and shorting out.

- 1/4x4 or 5" Galvanized pipe, 1/4 cap and 1/4 to 1/8 reducing union

- 1/4 barb to 1/8 NPT

- PC Metal epoxy putty (Very solid hold and super quick drying - USE GLOVES)

- Red RTV

- Thread Tape

- Stepper drill bit - I didnt have it but wished I did. Drilling paint cans sucks.

- 1/4in and 3/8 hose

Assembly:

Some people just pump air into the can but just like when you're blowing massive clouds at the stop light - you want the air to be directed at the wicks. It likely doubles the smoke output. I drilled holes into the 1/4 galvanized pipe and then drilled a hole just big enough for the union to slip through and then epoxied it to the can. Drilled two holes for the grommets and bolts with the wire and alligator clips attached to go through for the leads. Wrapped the wire around the wick the number of times required to get the target amperage and wrapped it around the bolts in the paint can. Used washers and nuts to clamp the bolts to the paint can and resistance wire to the bolts. At this point I HIGHLY recommend testing it to make sure you're not shorted to the paint can. That could be bad. Then put a hose barb in the paint lid and the ABS cap. Be sure to be generous with the RTV to make sure it seals up real nice. Use the hose to make the connections and you're ready to go!

Fill the can up with mineral oil and let the wick soak for awhile. Then you just turn on your pump, clamp onto your battery and plug your turbo inlet hose and you're off and smoking!

Im not the greatest at explaining myself so hopefully the pictures fill in what I didnt explain. Everything can be found at your local Ace Hardware - Its where I used to work and where I got the few parts I didnt have laying around.

I didnt get any pics of using it, but I think im going to use it again tomorrow because the first time I didnt use RTV and a lot leaked. I think I'll get better results that way.

Looks well thought out.

Can you post a "final assembly" pic of what's going on inside the can?

Here's results from a google search, it may have some helpful info,

https://www.google.com/search?q=automotive+smoke+machine&oq=automotive+&aqs=chrome.0.69i59j69i57j0l2j69i65l2.5613j0j8&sourceid=chrome&ie=UTF-8

Looks well thought out.

Can you post a "final assembly" pic of what's going on inside the can?

Thanks. I knew id forget something!

I also ran it again tonight... since sealing it that thin is a smoke beast!

And remember that its generating quite a bit of heat so your can will be warm to hot, be careful.

What would you estimate your total cost to be?

Assume you had to purchase all the materials.

(I bought a smoke/leak tester and am curious how much I could have saved, if any)

Many thanks, that first pic is especially helpful.

You're very welcome. If you (or anyone else) need anything else feel free to ask

What would you estimate your total cost to be?

 

Assume you had to purchase all the materials.

 

(I bought a smoke/leak tester and am curious how much I could have saved, if any)

One of the ebay/amazon type kits? I thought those were pretty cool for anyone who doesnt want to DIY.

Assuming you had NOTHING on hand and decided to build as seen here (pump and all) - about $70. That was just googling some prices. If you have things on hand, use HF items, or get discounts (i didnt use cheap prices, I used average full retail) you could get away with it for around $50.

Some people use an old pickle jar, old soldering iron, sock wick and whatever pump they have laying around and get it done for pennies - but the more you put into it the better it will be. Being a pack rat often helps for these types of projects

Sweet! Looks good! better construction that the one I made. My issue is I need an air compressor (My dads garage had one at the time I made mine), and my current garage does not have one.

Any pump recommendations that are cheap? What have other people bought for low pressure pumps?

Also my pressure regulator was not so great, I felt like it was still a bit over 2 PSI on the lowest setting :S

How well would this work on a charcoal canister? Don't they have valves that need to be powered/activated to open?

-Fish/pond air pump. I liked that the one I had was adjustable. Some people use a hand pump (I would get a foot pump) or use an adjustable propane regulator to lower pressure to 2PSI if using a compressor.

Certainly no need for a compressor to get 2lbs.

Sweet! Looks good! better construction that the one I made. My issue is I need an air compressor (My dads garage had one at the time I made mine), and my current garage does not have one.

 

Any pump recommendations that are cheap? What have other people bought for low pressure pumps?

 

Also my pressure regulator was not so great, I felt like it was still a bit over 2 PSI on the lowest setting :S

 

How well would this work on a charcoal canister? Don't they have valves that need to be powered/activated to open?

It should work - from a quick read it looks like the valves are vacuum activated so you can use a mity vac or something to work those. I would double check the vaca pics for proper procedure, but the smoke machine will leak test it at least.

Certainly no need for a compressor to get 2lbs.

 

 

 

It should work - from a quick read it looks like the valves are vacuum activated so you can use a mity vac or something to work those. I would double check the vaca pics for proper procedure, but the smoke machine will leak test it at least.

Hmmm, good to know, I will probably be giving my Subaru another look soon! I need to find an alternative to an air compressor haha

Seriously, this is pretty damn cool!

Well done, Sparkey. Thanks for the write-up.

j.