As the title suggest I have a bad leak coming from the small hole in the transmission. As it mostly only is leaking when the engine is running I'd suggest it's engine oil. Anyone have ideas from where it could be coming from ? Oil Pressure sensor and valve cover gasket are fine. Thanks

 

Mostly coming from the right side especially also from the clutch boot.

 

So taste it - I'll bet it is hydraulic fluid, not engine oil. Slave cylinder leaking, looks just like the fluid that came out of mine recently when I had to replace it.

It is possible you have two problems but if it is coming out of the boot on the slave cylinder you can be sure that you need to put a kit in there at least. Fix that, and see if the weep hole keeps leaking. Test it if it is and see if it is engine oil or gearbox oil. Someone correct me if I am wrong, but I think a rear main seal usually leaks between the gearbox/bellhousing and the back of the sump?

oooh did I say taste?! Silly me ...

 

The slave cylinder itself is almost completely dry. Also it's much more oily inside of the clutch boot

 

I think i know what my problem is. I didn't know that you have to use sealant on the flywheel bolts as they are open to the crank oil supply. This would also explain only dripping when engine is running as this would be pressurized then, right?

 

Yup

 

Okay so I tried to do everything that I could think of which could cause this issue. I put locktide on the flywheel bolts and I replaced the rear main seal for a new genuine one. But after starting the engine it still leaks from exactly the same place with fresh yellow engine oil. I really don't know where it could be coming from now. I really need help :(

 

Odd. There's an oil galley plug on this side of the engine as well, but it is not very likely to leak. If you cannot see anything obvious with naked eye, get an UV oil dye and a UV light, it will help you identify the source of the leak.

 

CAS/rearcam cap leaking into bell housing at the top and making its way down south?

+1 to dye and a black light to tracing this sort of issue.

 

This. 9 times out of 10 it's not a leaking RMS, but petrified CAS o-ring leak that's flowing down.

 

Alright thank you guys I'll look into that. Shouldn't I see a leak like this on top of the bell housing tho?

 

it's sneaky, since hot oil is very thin and tends to just go straight into cracks. take some acetone, wipe down the area underneath the CAS, inspect the rag, swipe with a finger to verify it's clean, then go for a ride and hit it with another paper towel. if it's oily, bewm, CAS oring.

 

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It's coming out right away tho, instantly after I start the engine fresh engine oil starts dripping 😭
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I have battled this a few times. My current procedure is to run dye in the engine oil and use the light to examine all of the suspected areas. On all engines that the flywheel bolts run through the crank flange into the crankcase I use red loctite on the bolt threads and under the heads. I also use some silicone around the flywheel bolt holes on the crank side. Just a very small amount just around the hole. When replacing the RM seal, you have to be meticulous and I also silicone them in with the right stuff or ultra grey/black. I also do the input shaft seal and gasket on the transmission.