DIY Smoke Machine for Leak Testing?

[cribbj]

Anyone tried to make your own smoke machine for leak testing? I think it would be a real handy accessory to have for leak testing intercooler piping, etc. Commercial smoke machines go for around $900, so it's way too much to purchase for limited use.

Plenty of DIY material out there on the Internet, and I'm getting interested in building one. I figure a bottle of nitrogen, a very low pressure regulator, and some canned smoke for smoke detector testing or a halloween fog/smoke generator ought to round out the major components, and I'm thinking of using something like an eductor nozzle to introduce the smoke into the system as I'm pressuring it up.

I've got a leak somewhere in the evap system of the Italian stallion and it gets pretty stinky sometimes in the cabin. Fuel tank fumes are a known issue on the 550 Maranello, so I'll probably have to pull the tank and replace some hoses and gaskets, but it would be useful to leak test the system before it comes out, to get an idea where the stink is coming from.

 

[V8Datto]

cheap smoke machines on e-bay go for $50

surely you can't make one for that?

 

[Cobber]

Check your hoses, I bet fuel fumes are leaking out through the hose.

Here is friends smoke machine in action.

http://www.youtube.com/watch?v=TbBSS8ocBW4

 

[cribbj]

cheap smoke machines on e-bay go for $50

surely you can't make one for that?

You're right, but those don't make any pressure at all, and to leak test something, you need a bit of pressure. In the case of the evap system or fuel tank, not more than a psi or two. So the eBay smoke machine, or some smoke in a can is part of my scheme, and the bottle of nitrogen with a low pressure regulator is another part. And I'm hoping the eductor nozzle is the bit that ties it all together. I just scored one on eBay for $15 so we'll see how it all works. If it doesn't, then they'll joing the rest of the stuff in my very interesting junk pile.

Check your hoses, I bet fuel fumes are leaking out through the hose.

Here is friends smoke machine in action.

http://www.youtube.com/watch?v=TbBSS8ocBW4

Thanks Andy, I'm thinking it's hoses too, but they're tough to get to in the Ferrari without disconnecting and pulling the tank out. Then once the tank is out, it's tough to pressure test the hoses that stayed in the car. So I'm going to try to pressure test the whole thing, localise the leaks, then replace those hoses, plus reseal the tank once it's out. Bummer, but we can't see Youtube videos from over here in the desert.

 

[Cobber]

Fuel vapour permiates through the hose if it is old or the wrong spec, I doubt if you will get smoke at a coupe of psi to do the same.

I have some info on fuel hose somewhere I will send it to you. Under pressure some hoses can end up leaking quite a bit of fuel vapour.

Many years ago in an off road VW buggy I had we injected diesel in to the exhaust from a screen washer pump. The guys behind would think we lunched an engine and also back off because they couldn't see where they were going. Lot's of fun.

 

[cribbj]

The fuel system on this car is pretty complicated. Dual everything, and they kept it all segregated as far as I can tell. Each bank of the motor has it's own dedicated system, with no commonality between them as far as I can tell.

Here's some pics and diagrams, and I'm suspecting one of those corrugated hoses on the right to be "one" of the culprits that's leaking and/or the vapor separator on top that has the dent/kink in the middle of it. Should be fun finding the leak, and even more fun getting the tank out through the trunk!

 

[Cobber]

Typical Italian, loud emotional and dribbles when under pressure.

Just be thankful it's not a military vehicle or it would have 5 reverse gears.

 

[cribbj]

Too right

After getting stuck into this car a bit, it does make me appreciate how well engineered the Japanese cars in general, and their engines in particular, are. I've also been amazed at some of the just plain shoddy design I found in the BMW V12, so I don't know that the Germans are much better than the Italians. They seem to use a lot more metal, but still make some real howling errors......

It's just too bad the Japanese (and Toyota in particular) REALLY suck at exterior styling. They could own the auto industry if they'd ever get their design studios sorted.

But this Ferrari fuel tank and fuel system are something: Two of the most complicated (and expensive) fuel pump "packages" I've ever seen are hung in the tank (without any PWM electronics driving them, so they run flat out all the time), two sets of fuel filters, two supply lines, two return lines, two separate fuel rails, two pressure reg's, two separate fuel cooling systems, using two electronically controlled, A/C freon cooled exchangers, four rollover valves, a fuel vapor separator, a two way tank breather valve, numerous check valves, two charcoal canisters and two purge valves. And it's all held together with cheap rubber hoses.... So, no wonder it leaks?

I am so tempted to rework some of this, but at the end of the day it's a Ferrari, not a Supra, and I need to be very careful what I contemplate changing, even if it's an obvious improvement.

 

[Zuffen]

You could use a match of cigatrette lighter?

Seriously, I'd be inclined to do what gas fitters do.

Apply mild pressure to the sytem (or one hase at a time) of 4-5psi, use soapy water and apply it to the hose and joints. The internal pressure will make the soap suds blow up into a bubble where the leak is.

If I had you're problem that's how I'd attack it.

If I had your Ferrari problem I'd sell it before it cost much more!

 

[XR8tt]

Is it smelling of fumes or leaks ???
Check charcoal canisters are connected to engine - tank ...
If not whilst being stored in garage it will smell of fuel fumes from tank etc...
One EPA system that's a good thing, with out losing performance but many disconnect...

 

[cribbj]

Apply mild pressure to the sytem (or one hase at a time) of 4-5psi, use soapy water and apply it to the hose and joints. The internal pressure will make the soap suds blow up into a bubble where the leak is.

If I had your Ferrari problem I'd sell it before it cost much more!

Rod, you have more F-car ownership experience than me, but I'm thinking this is just part of the "Ferrari experience". As JBrady said, with all my other non-running money pit car projects, it was good preparation for owning a Ferrari.

Anyway, this is the only "issue" that I'm aware of with the car....at the moment, and it's fairly well known on the Ferrari boards, and it's a straightforward fix. Some take the shotgun approach and change every valve & hose and call it good, but I'd kinda like to know where the leak is/was, even if I do wind up changing every valve, hose & fitting just for prevention.

Is it smelling of fumes or leaks ???
Check charcoal canisters are connected to engine - tank ...
If not whilst being stored in garage it will smell of fuel fumes from tank etc...
One EPA system that's a good thing, with out losing performance but many disconnect...

Yep, gasoline odor inside the car, just after filling up, and also after extended driving. Interestingly there's a good whoosh of fumes that comes out of the filler neck whenever I open it, so the system "seems" like it's holding pressure OK. Maybe it's something as simple as the purge solenoids not activating to clear the charcoal canisters. When I get home I'll have to put the scope on them to see if they're getting activated from the ECU.

I agree about it being a good system. After the engine swap in my Supra, I initially had it disabled and had pulled the charcoal canister out to gain some space for a catch can, but after a month of a smelly garage and a complaining wife, I hooked it all back up again and the Supra has never had gasoline fumes since.

 

[XR8tt]

Clever Mrs .. Lol... Ahaha

Could even be breather is not looped as it should ???

...

 

[johnybpaul]

Hi...one of the method for preparing homemade smoke machine. By using this we can find leaks in intake, exhaust, etc. First take a wet/dry vacuum, some dry ice and water, and a home made regulator, then connect the vacuum hose and regulator to the vacuum on the exhaust side and put the water with the dry in a the vacuum then turn on the vacuum. Then we can easily detect where the leak is situated.


leak test for storage tanks

 

[Lambo]

diy smoke machine

Hi John, if its any help, i have always used a piece of muslin, or cheeze cloth as its called, just setfire to it put out the flames, let it smolder, and it gives all the smoke you will ever need for cheap, may not be a idea around petrol but i have used this method for years to trace water leaks around door rubbers etc, just fill up the cabin and watch for the smoke, just turn on the heater fan for a little pressure

Regards
Graeme

 

[cribbj]

Thanks Graeme, we found the problem eventually, and it wasn't "diagnosed" per se, but by hearsay from other owners.

The gaskets under those vapor recovery valves on top of the tank have been found to deteriorate and start leaking, and that's evidently the most common source of fumes other than the plastic rear pump covers that develop stress cracks. Most of the soft goods in Ferrari's fuel systems built prior to 2004 or 2005 don't handle ethanol very well. I think in the V12 models, the 599 was the first model to handle ethanol in any quantity. In the V8's it was probably the 430. Of course the rest of the OEM's have been building ethanol capable fuel systems since around 2000, or before.

Anyway, it's all sorted now with some new valves and gaskets

 

[XR8tt]

I was just going to get a muslem too....Lol....