Oil Return Leaking CS Turbo
 

K so I installed my CS turbo, along with a 3” SS catless downpipe. Got it at 0% WGDC so I can drive it while I wait on my tune.

I was checking around for leaks, it appears the oil return line is leaking hella bad, throwing oil everywhere. I’m going to try to tighten it a bit more, but anyone have suggestions on a fix? Is it too hot for some sort of sealant?

And does anyone know the OEM Part# for the turbo side and block side gaskets?

Edit: What’s the lb-ft for these bolts? I tightened them more, they seemed to be kind of loose, maybe I forgot to tighten them.

http://www.mazdaspeedforum.org/forum/foru...-turbo-189896/

there are some pictures of the part number in this

Thanks!

I tried tightening it a little more, it slowed the leaking but it still drips after a short ride. I’m gonna swing by the Mazda dealership tomorrow and pick up the gaskets.

Ugh, I fucking told corksport about this like 2-3 months ago, since I had the same issue. I went out and even bought new gaskets and it still leaked.

So, it turns out that the pre-drilled threads on the turbo are too short therefore the gasket is not sealing. Get two small washers and add them between bolt and the return line.

I can't fucking believe they didn't fix this shit cuz it is a fire hazard when oil is leaking down the dp.

Dude you are a life saver! I’m going to try this ASAP, I’ll contact CorkSport if it does work.

Let us know if it fixes your issue.

So I had the exact same issue but with a Garrett turbo.

The bolts for the turbo and bolts for the engine block on the return line are not the same. The bolts for the block are longer and bottomed out without tightening the return to the turbo. I swapped the bolts and fixed my issue. I was going crazy, sanding, using copper gasket maker, everything.

Maybe that's your issue, if they machined the holes identical to the ko4/ Garrett chra it could be as simple as swapping the bolts. One of the linked threads shows the different lengths in pics

It did! I went and got some #10 washers, the ID was little small so I filed them out a bit. But I could see as soon as I tightened it all the oil that was leaking squeezed out from between the gasket and the turbo. Went for a short drive and saw absolutely no more leaks.

I am going to contact CS ASAP about this. Oil was leaking on my downpipe, insanely high chance of catching fire. Other than that the turbo is fucking awesome, takes a little longer to spoil but man does it push air.

It was mentioned in the manual that the bolts that go into the block are longer, I made sure to keep it that way. However upon close inspection it looks like the bolts to the turbo are just barely too long, maybe .5mm. They contact the CHRA and prevent it from sealing like others mentioned.

Awesome, glad you found the issue before you had a real problem. I have the CS turbo also but I did not have any issues with the bolts or leaks

Just found out that I have the same problem. Glad I came across this post before losing my fucking biscuits about it.

Was this on the CST4? Is it recently purchased? Im due for a new turbo and hoping CS has addressed their issues (creep, leaks, etc.). I'm stucking between CST4 and BNR S3 and really leaning towards CS.