gweelie

I was considering doing a diy smoke test do find an exhaust leak and the first thought was hooking up a party fog machine. I have reservations about putting something foreign like that into my engine, so my question is, has anyone done anything like this before or does anyone has any suggestions?

scuba

Seafoam!!

NwRunner

X2 Put it in the PCV, let it sit for 5, start is up and watch the smoke!

az4x4runner

If you do the seafoam, I'd use the vac line on the brake booster. Pour it in with engine running, very slowly. It'll smoke.

edit: it's been a while since I used the stuff, but from what I remember after your pour it into the vacuum line, shut the engine off and wait 10 mins or so, then once you fire it back up the smoke begins.

swampfox

seafoam is good, just make sure there is a breeze blowing away from the truck.you can also use a piece of hose to listen for leaks.

gweelie

Is there a way to use seafoam for a vac leak as well, or does it need to run through the engine to smoke? Appearently my runner is full of vac leaks, exhaust leaks and oil leaks.

Kiroshu

Bad ideas... I would only recommend sea foam in your gas tank... You can hook up at a shop a proper "Smoke machine" that will tell you any vac leaks or exhaust leaks.

gweelie

I know a shop has the fog machines, I'm just trying to avoid shops and their prices.

Kiroshu

Well unless the leak is big a regular old fog machine is not going to detect small leaks. A proper "smoke machine" acctaully puts pressure to the system(vac/exhaust) to force smoke through small pins holes. And some smoke machines have leak gauges on there to tell if its a .20 .30 .40+(thousands) leak.

gweelie

Well I have been talked out of the idea, but for fun, my idea was to take the filter off of my shop vac, clean it out and then hook up the hose to the exhaust end of the vacuum. Then blow the smoke into the suction, with the exhaust forcing the fog into the air intake. I'm not doing this, but does anyone think it might have worked?

barrel roll

Quit being a wussy and suck Seafoam through a vacuum line.

Kiroshu

^^^

barrel roll

It is safe. We've been doing it to motors for years.

If it were bad for the motor, the instructions on the SeaFoam bottle wouldn't tell you to do it and there would be class action law suits.

whokrz

You can use a section of hose to listen for leaks as swampfox suggested.
Exhaust leaks are normally at the joints I think there are 3 - 4 joints depending on how chopped the exhaust is. If it is a large exhaust leak you can feel it if you get your hand close to them.
Vacuum leaks can be at joints, hose connections and cracks in the hoses. If you listen with a hose you will hear a hissing sound where the leak is. If it is a really big leak it will almost sound like a loud bearing that can be heard without a hose. People also spray carb cleaner and other flammables around the engine bay which raises the idle if it is close to a vacuum leak