I'm in the process of completing my boost leak test before my repeat tune.. I originally just tested the inter-cooling piping up to the throttle body... After going to the tuner and getting on a dyno a couple serious leaks appeared off the turbo housing. I've found/fixed solved the problem coming off the housing of the turbo. *bolt missing off the actuator

Turbo's a TD05H - 18G.

I figured I'd find all the leaks before disasmabling the exhaust manifold and turbo to replace gaskets - Turbo inlet and Turbo outlet.

As I've got slight exhaust leaks coming from those two area's. But I'm at a loss as to know if air pressuring up the turbo should be leaking on the exhaust side? Shouldn't there be a seal that keeps the pressure building up from one side to the other? Am I looking at this all wrong? If this is right, how can I maintain pressure on the system knowing it'll dump out the exhaust pipe?

I've also found mixed opinions on whether I should be applying pressure through the intake manifold. If I move my engine to TDC will all Intake valves be closed? As the tuners said he's found some small leaks coming from injector o-ring gaskets before. Would it be better to smoke test the intake manifold and pressure test inter-cooler piping to turbo?

Thanks for any feedback or suggestions. I really appreciate the help.

Thanks,
Josh

 

Air coming out of you exhaust spins the exhaust wheel which spins compressor wheel which creates boost, and yes the turbo is internally sealed. There should be no air leaking out the exhaust side, although some people disagree I say use gaskets where the downpipe meets the turbo, is this where its leaking form?


I used compressed air to check for leaks within the IM it worked fine for me, perhaps I was lucky and most my valves were closed for the most part

 

The leak seems to be coming from the turbo inlet (where turbo mates with Exhaust manifold) and outlet (where turbo mates to exhaust down pipe) TD05s got an internal Wastegate *if this info is needed*... would 20lb's of air in the compressor housing push ~~5lb's of air out the exhaust housing?

I know the exhaust side compressor screw is larger so it can place more torque on the intake side of turbo. Clearly I'm replacing the gaskets on the system but before I started taking everything down I wanted to ensure I found the leaks first then replaced all gaskets in one go then do a 2nd test after and hope I found the major area's as on the Integra manifold/turbo has the be completely assembled off the car then put on in one giant piece.

As for when you did your leak test 2kdrift.. How long were you able to hold the pressure? I've read on a couple how-to's that 1psi / second is an acceptable rate of loss. *unless I completely misunderstood * when connecting through the intake manifold. Im reworking my leak tester with some steel pipe and quick connect's so I can just keep the compressor hooked up with 10-15 lbs' of air.. The valve stem just wasn't working for me as the leak's are too large currently.

My biggest leak was on the bolt missing from the actuator which has been replaced and the BOV. I had to Type S Greddy bov hooked up with boost and vacuum lines.. which was causing the BOV to just blow open on the leak test as it didn't have any pressure reaching the top of the bov with the TB plate closed.

Thanks for the response.

 

What you are describing is more of an exhaust leak, which will have less air to spin the turbo in turn creating less boost, only fix really is remove turbo clean both flanges and install new gaskets

I think I was losing something close to 1 psi per sec, I later found some minor leaks, I was boosting about 20 PSI (read off my boost gauge). The thing is any decent size boost leak was very noticeable, for the smaller leaks soapy water in spray bottle helped alot

What i did was hookup the leak tester at turbo inlet and opened TB plate manually...tested the whole system, then used my soapy water starting from the turbo and made my way to IM

 

So I have two leaks that seem unfixable (without complete replacement)... One off my throttle body... Where the cable for gas pedal connects to the butterfly valve and one from the screws that connect the external actuator on the side of the bell housing. I've tried Teflon tape and paste (rated at higher temps) to stop those without luck.. Both locations only show up in the higher PSI range and with them I was able to maintain around 15psi/1.5sec... System seemed to hold 1-2 pounds for 30+second before I just dump the pressure.... Yes as far as the exhaust leak or air escaping the outlet and inlet connections on the turbo... It felt like air was coming out because of the boost leak test which had me concerned the pressure was going from one said directly to the other instead of possible having open valves dumping to the exhaust. I've tightened all the bolts down and hit the exhaust pipe to down pipe connections and was unable to find any leaks on a cold engine.

Would a warm engine show this exhaust leak easier then a cold engine?