How to do a boost leak test

[zebiraross]

Because of some recent pm's I decided to do a little how-to on boost leaks. One thing totally overlooked by most boosted sleders, is a boost leak tester. It's a simple divice, that can nail down air leaks from your turbo to the throttle bodies. And when you have trouble during the season tuning or things not running right it's the first place to look, for leaks. It's simple to make. The way I made mine mine is to get some pvc pipe about 8" long. Cap one end and use the glue/cement you use for sprinkler system for the cap so it won't blow off when you pressurize your system. Go to a local tire store and get a nice stainless tire stem. drill a hole in the top of the cap and screw the stem in (make sure it won't leak air). Bam you have a boost leak tester. To use it take off your prefilter cage or filter on the turbo inlet and put the pvc pipe in it's place, clamp it in. Set your air compressor to about 30 psi. Make sure your radio is off and things are quiet so you can listen for leaks. Turn your compressor off so it won't kick on when pressurizing, you need to be able to listen for leaks. Pressurize your system watching your boost gauge and pressure up to 20-25psi. Now take the air off the stem and listen. Some boost leaks are obvious and you can easily find them by listening and feeling with your hands. Others are easier to find by getting some soapy water and putting it on ALL places where air can leak (silicone couplers, carbs, throttle bodies...) Look for air bubbles, and listen for leaks. Watch your boost gauge. Your not going to be able to hold your set boost pressure for ever because air is going to eventually leak through the throttle bodie/carb butterflys and past the intake valves that are open. But you should be able to track down most things. Hope this is helpful.

 

[Climbmax]

SMRT.......i never used the valve stem but coupler instead.
Thanks
RS

 

[sledstew]

Shaving creme works well for this type of issue

 

[Tinkeritis]

Cool. I will check into doing this on my sled. Great thing to add to the preseason check list!!!

 

[skidoomutt]

just did this to my sled found a few leaks a couple major ones on some welds. It is definatly a good thing to do. I used a pvc cap in my intake and a regulator with a quick connect air fitting so i could regulate the pressure, i dont think you want to go more than you boost level is set at because you would just open your waste gate. dont forget to plug your exhaust otherwise the air will just flow out. I set my regulator till my waste gate opened, its easy to calibrate the waste gate at this point as well, to know were it is set. I set my regulator at my boost level and let the air flow to find my leaks after i new i had some buys you a little more inspection time. This is well worth the time and should be done..

 

[mattymac]

most hardware stores carry gas pipe leak kits that have a small gauge, shrader valve, on a piece of steel pipe thats threaded on the oposite end of the shrader valve that you can adapt alot of fittings/setups on it. I use it for testing Ucoolers but could be doubled as a boost leak tester too, even though you just use the boost gauge anyway. The valve is around 10.00.

 

[arfrce]

Hey can you post a picture of the ones you guys made. I might make this a sticky. So new guys can see what you are talking about . thanks Jeff

 

[TTE]