Leaking compressor housing

[Kenneth Schlorf]

After doing multiple boost leak tests and finding a leak at the compressor housing of my PTE 5858 (purchased spring of 2014) I came here for answers and found lots of information regarding the o-ring and sealing the compressor housing against the backing plate with copper spray or RTV. So I tried it and then thought I might have put too much RTV and it could squirt towards the inside of the compressor housing and plug up my intercooler or make its way through the engine (I basically put a slightly concave amount from the o-ring to the outside edge). I never ran the engine with the RTV and took the compressor housing off the next morning to clean it up (some had squirted far enough where I wouldn't have felt comfortable).

Here is the point of my thread for the benefit of others with leaks at the compressor housing:
It was at this point that I realized that two of the bolt holes that help to hold the compressor housing on were drilled/tapped deep enough where air was leaking out the holes (with the bolts in them). One was closest to the nozzle/output and the second was just upstream from it (though much smaller). After using teflon tape on the two bolts (not sure if this is the long-term best solution yet) and installing a new red o-ring, the system held to 30psi where I stopped.

I am sure like most boost leak fixes, solving the leak significantly helped by decreasing the amount of time it takes the turbo to spool up and it impacted the setting of my MBC by increasing psi about 20%, so I had to turn it back down.

I hope this helps someone else solve their compressor housing leaks!

 

[1990TSIAWDTALON]

A small amount of Grey Vibration Resistant Permatex RTV works great and holds the bolts in while sealing. I used it on every bolt on my engine and on my HX40 compressor cover with great success also. Just adding this to your aolution. I think it for sure will outlast the teflon tape. We used it on every fastener when I worked at Cobalt Boats since they vibrate a lot also and it kept all the fasteners in place unless needing to remove them.