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Diagnosing oil leak- RMS?

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Old 10-20-2015, 09:39 PM
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Default Diagnosing oil leak- RMS?

I going to have to stop going under my car. Every time I do I notice a new gremlin. I'm pretty sure a have a failed rear main seal now. I've been noticing a couple very small drips on the garage floor but thought it might be residual from a previous leak from a loose oil drain plug. When I was under the car last week i noticed the bottom of the tranny was covered in oil, but I was hoping it was just residual tranny fluid from the mess I made filling it. However the rag has black on it, not red tranny fluid. And tonight I noticed a drip from the bottom of the spacer plate. Looks like its maybe leaking down and then getting blown all over the bottom of the tranny when I'm driving.....maybe even more so when I'm driving at higher rpm.
Is there anything else I should look for first before planning on dropping the tranny? What a drag, I was so careful putting that seal in when I did it.

Last edited by MX-Brad; 10-21-2015 at 11:31 AM. Reason: typo's
Old 10-21-2015, 05:15 AM
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Could be oil pan also. Think that is where mine is leaking. Not happy about it. Does not leak when running, only when I turn it off after running.
Old 10-21-2015, 06:19 AM
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Make a very detailed inspection of the rear intake manifold to block area and the valve cover gaskets as well. The rear intake area can leak and it will find the block plate and flow from there down. Will look like a rear main seal. I'm not sure which is worse though, rear main seal or intake gasket...

Check the dipstick to block seal as well.
Old 10-21-2015, 07:37 AM
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Check back of intake gasket. Never use a gasket in that area. Only use a thick bead of silicone rubber. Also check PVC grommet.
Old 10-21-2015, 08:39 AM
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Great ideas. Car is still on stands so will get out there this morning and check all that.
Thanks guys.
Old 10-21-2015, 11:43 AM
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VC gaskets are not leaking, dipstick tube is not sealed well, but it does not appear to be the source of the drip. Oil pan gasket looks good, but since it is the blue 1 piece Felpro I figured it couldn't hurt to snug a bit more especially on the ends. I know I torqued the valve cover gaskets to spec but they leaked until I tightened them before the car even ran, so maybe those gaskets need a bit more torque. I didn't have a chance to get a real good look behind the IM, but a quick look from above and below leads me to believe it's dry. I cleaned the area real good and will take on a work trip today (about 60miles) and check it again tonight.

Also I RTV'd my torn CV boot last night. I'm waiting on a couple boots from Martin. Says he has a new boot he's using that will clear the shock. I know I could have got the Audi boot, but I like buying from Martin for his continued support.

Also, adjusted the slave rod some more. I did that last week and it helped with some of the noises the tranny was making, I gave it about another half turn today and on start up the noise seems to be completely gone. Will know better when I'm on the road this aft.
So glad I drilled a hole through the end of the rod. With exhaust in place it's pretty cramped to get any tools in there and I can just stick an awl in to hold it from spinning when adjusting the nut.
Old 10-21-2015, 02:51 PM
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Every oil leak on a SBF shows up on the front of the block plate. Doesn't seem to matter where the leak is coming from, that's where it shows up. Assuming it was installed correctly to begin with, a leaking RMS is actually pretty uncommon.

Use a dye tracer kit. You can also sprinkle baby powder or corn starch around various places to find hidden oil leaks.

Most repair shops have a smoke machine. They inject a petroleum base smoke into the crank case. Where the smoke leaks out is where the oil is leaking out. That's how I found a leaking fuel pump block off plate.
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