Turbo issues

[VIN18M]

Ok, so I'm going to make a boost leak tester this weekend.

Newbie question, I have a 17psi actuator but am running 24psi via the boost control solenoid. I should still be seeing boost leaking via the wastegate at 17psi right?

 

[evo-gsr]

You only need to pressurize the system to about 10psi by using the regulator on the compressor.
You will hear the air escaping if you have a leak. There is no need to put any more pressure than that through it.

 

[VIN18M]

Cool, thanks mate.

 

[4piknup]

I feel you need to leak test all the way up to your boost level of 24psi. As you have a ebc, it will be shut and no pressure will get to the wastegate. You could bypass ebc for testing, or matbe if ignition is on, the ebc will operate?

Sure, test at 10psi and see how it looks, fix leaks and then increase pressure...
Often a leak will not show till you get higher up on the pressure. Mine wouldnt even hold 6psi when I started. I had leaky intercooler bolts, porous welds, leaks at silicone joiners, tb shaft seals, even the biss screw.

I dont know what a good result is tho. Mine drops from 12psi to 6psi in about 45sec. Its better than it was, and some of it must be going past rings. I think if you get to your pressure level and you cant find any leaks with bubbly water, then thats fine. Any pressure drop must be past the rings at that stage.

I have a thread showing my tester on here somewhere. The poly end fitting slips in the silicone hose at about 10psi. Spray with hairspray to get better grip, (this applies for all silicone connections.
Remember your pcv valve can leak into rocker cover.

Happy testing. I have tb seals if you still have evo tb.

 

[4piknup]

No boost will leak out wastegate. The actuator will move but no pressure will drop.
You are pressurising to the closed valves, either the back of the closed intake or the front of the closed exhaust. Enless your engine is stopped right at tdc or bdc. (Just look at balancer to check its not)

 

[evo-gsr]

Then why do you need wastegage to open?

 

[VIN18M]

Ok, thanks for the info Jack.

I'm leaning towards it being a wastegate issue. If it's leaking past the gate at 10psi without any leaks around the silicone joiners, then I know its a wastegate issue. I'll just up the pressure gradually to 24psi.

I'm thinking I'll wire the gate shut then and see if it holds boost, before pulling the turbo out, dump off etc.

 

[4piknup]

Then why do you need wastegage to open?

Just checks the lines and bellows. And maybe you might like to confirm when it opens.

 

[4piknup]

There will be no pressure in the exhaust during a leak test, so nothing can escape past the gate.
Bypass your ebc. Plumb straight onto wg actuator.
Give it 10, fix the leaks.
Increase it up to your 24, keep fixing leaks.
If there is no leaks to fix, pull your turbo.
But when you have intake hose off, check your impeller isnt loose.
Try to ignore air coming out rocker breather, unless its back flowing past the pcv.

 

[4piknup]

Are you thinking to wire gate shut to see if it builds boost like before? Sounds like a good idea. Even before you leak test.

 

[VIN18M]

Yeah plan was to wire it shut to cancel the wastegate out as a problem altogether.

If it doesn't hold boost then I'll try for boost leaks, once they are fixed if it's still bleeding boost somewhere then I'll pull the turbo out and see if the flapper has come off the wastegate or jammed open somehow. Or worse...

I'm running a catch can with a breather to the airbox so this will let the air escape.

I may have to sleeve the pipe I use to make the tester as I can't imagine it staying put for very long at 24psi...

 

[VIN18M]

Spent the afternoon making the boost leak tester, my intake goes from 3" to 4" but I couldn't find any 3" PVC so it's a bit of a beast.

Will test the system next weekend and see what the results are, thanks again everyone, I think it was well worth the half hour or so to put this together.

 

[VIN18M]

Soooo...my BOV was jammed open.

:S

 

[evo-gsr]

Recaros here we come!

 

[4piknup]

Soooo...my BOV was jammed open.

:S

About the best bad news you can get.
How did the boost tester go? Did you give it heaps

 

[VIN18M]

I didn't end up testing it...
I disconnected the valve to take the intake pipe off and hookup the pressure tester and noticed that the valve was jammed 3/4 of the way open.
Pulled the valve off and gave it a good clean, it had a fair amount of gunk collected inside it (second hand bov). Lubed it up and refitted it, car was completely back to normal, holding consistent 24psi to redline.
Before doing all of that I pulled out the hot side piping as its rubbing in a few places, namely air con compressor and thermo shroud, so that's something that needs to be addressed as I thought that's where the leak may have been coming from.
Going to get onto that in the next couple of weeks and then pressure test the whole system.