boost leak test - ideas?

[EL]

Hey guys!

Need to run a boost leak test on the car. Trying to find something to block the tip (3.5inch) which i can then drill a small hole into so i can pump air around the system. Any ideas what i can use?

 

[LEE69]

Tennis ball.

 

[dav3]

Have a look on plumfix web site as plumbers use an expandable bung when pressure testing a newly installed sanatory system. When AmD pressure tested my car they put the bung in the bottom of the charge pipe.

 

[dav3]

Sorry not plumfix screwfix. Here it is anyway. Its a 4" plug but will fit in 3.5"
http://www.screwfix.com/prods/62513...m;jsessionid=FFPOE41A054HACSTHZOSFFI?ts=27623

 

[EL]

thanks mate! Just got the expandable bung, time to get testing

 

[james walker]

and how would you test for boost leaks please guys....

 

[EL]

@james walker: What you need to do is pump air through the system (10-20psi) and listen for any noise coming from the pipes. You should be able to hear something if you have a boost leak.

@dav3: Got the 100mm bung but don't think it will work. Tried to fit it in and even around the TIP which is 3.5inches side to side but no luck. Think i need the 150mm and get it to sit around the TIP. Are you sure AMD tested your leak from the bottom of the charge pipe? I am trying to do it from the TIP as that to me seems the best place

 

[wild willy]

Fecking Ametures .
i'm a professional so this is what i do .

can of hair spray clamped to seal off tip mouth. disconnect feed into n75 valve and apply air via this hose, connect both remaining n75 pipes together.
pressurise to 10 psi (no need to go higher), slacken off oil filler cap to allow air to escape that leaks past the valve train.
Aim hair spray can carefully as it can be a missile if it breaks free.

 

[EL]

Fecking Ametures .
i'm a professional so this is what i do .

can of hair spray clamped to seal off tip mouth. disconnect feed into n75 valve and apply air via this hose, connect both remaining n75 pipes together.
pressurise to 10 psi (no need to go higher), slacken off oil filler cap to allow air to escape that leaks past the valve train.
Aim hair spray can carefully as it can be a missile if it breaks free.

Hair spray thats where I am going wrong

Cool lets give that one a go. Sis where are you I need your hair spray!!!!

 

[dav3]

Yes mate they did it from the bottom of charge pipe by dipstick as I was trying to find out if my dv was leaking. The bung is good for 4" pipe you tighten the nut up which squashes the rubber and makes it fill the pipe, use it at college to test my work.

 

[Gubien]

Fecking Ametures .
i'm a professional so this is what i do .

can of hair spray clamped to seal off tip mouth. disconnect feed into n75 valve and apply air via this hose, connect both remaining n75 pipes together.
pressurise to 10 psi (no need to go higher), slacken off oil filler cap to allow air to escape that leaks past the valve train.
Aim hair spray can carefully as it can be a missile if it breaks free.

If attempting to run like 1.35 bar, then you need to make that amount of pressure?
I've experienced a boost leak around 1.2, but not at 0.8.

Should your procedure hold 100% air tight? Or will there be need for apply pressure constant?

 

[wild willy]

If attempting to run like 1.35 bar, then you need to make that amount of pressure?
I've experienced a boost leak around 1.2, but not at 0.8.

Should your procedure hold 100% air tight? Or will there be need for apply pressure constant?

Applying too much pressure can cause damage as many of the components such as the air intake and breather facilities aren't mean't to carry boost. I've had faults that don't show at 5psi but do at 10 psi. I can see the logic in testing to full boost pressure but if you consider a hybrid can boost to 1.8 bar, thats not the sort of pressure i'd want to pressurise my entire engine to. Its a personal choice i guess.
Once up to pressure the system should hold the pressure and then gradually leak away through the valve gear and maybe some oil seals. I use a general purpose foot pump to apply the air.

 

[Gubien]

I did this yesterday, but I actually disconnect the breather cap to the TIP(blocked of tip) and the oil cap as you describe. Can you remember how fast the pressure a descreasing? I make 0.7 bar and I cant hear a fuzz but the air escapes.