Installed New Water Pump, Thermostat, what do you think of this oil leak?

This weekend it was beautiful in Chicago, put in my new PIERBURG water pump from Warehouse33. Had a low temperature thermostat I bought at LN Engineering during a tech session months back. Replaced the serpentine belt and coolant. Followed Ahsai's procedure for pushing all the coolant out, it's always easier when somebody else has documented it: https://rennlist.com/forums/996-foru...pump-tips.html The good news is that the pump I removed was the original pump, I guess the other good news is that it was in pristine shape at 39K miles. Was manufactured the 52nd week of 1998: Replaced my plastic coolant hose barb with a metal one from Home Depot, the only thing I don't like about this is that it is a little too big for the application and had to put regular hose clamps on vs. the OEM spring clamps. I had bought the vacuum system for the coolant refill.....OMG, one of the best tools I have ever bought. In case you are not familiar with it, you have a tapered rubber piece that makes a fit to the expansion tank. You put a compressed air line (use a little carpenter's compressor) and send air through it, it draws a vacuum in the system via venturi effect. It draws about 27" mercury in about a minute, then just close the valve and the system is at a vacuum. Then you hook this hose up which will carry the coolant into the system. Put the hose in the bucket, open the valve and physics does the rest. Atmospheric pressure is greater than the system pressure so the coolant is drawn into the system. As the system fills up, the vacuum starts reducing (coming closer to atmospheric pressure). It literally took about 60 seconds for it to fill 5 gallons of coolant into the system. I ended up topping off the reservoir with about another 750 ml before it was all done, just did that by pouring it in. Oh so cool of a tool. Going underneath the car to change the oil, I noticed an oil leak that appears to be from the RMS or IMS flange: I really didn't pay much attention to this, but took a picture....looks higher than the leak in the previous three pictures. don't know if this would be normal for a RMS/IMS seal leak: I went back to look at the pictures when I bought the car, and it appears that the dealer I bought it from probably cleaned up that area. Here are a few pictures from the day I bought it: It looks like it was cleaned up based on this picture: So I cleaned up the bottom of the engine and will look at it again in 1,000 miles or so. Any words of wisdom besides keep looking at it? I don't think it will cause any damage or failure modes, would it?

Very nice write up Paul! I would definitely clean up that whole area very well and then document what you see... check back in a few weeks and see if you can pinpoint where its coming from. And don't forget to check your oil filter regularly!

Nice write up and photos! Glad my coolant flushing method works out for you too. The vacuum refill tool is truly a joy to us. One thing I found is it's really not necessary to put the pail higher than the reservoir. The vacuum will suck all the coolant even if you place the pail on the ground. I know because I've tried it

I absolutely hate that unit of measurement. Almost as much as I hate slugs.

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inHg?

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yES

You would rather see kPa?

And when I refer to slug, I'm referring to 1 slug = (1lbf*s^2)/ft, not the the tough skinned terrestrial mollusk.

Haha, I was wondering what that was.

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NO. I love psi. Why? It's so tangible. I know what a pound is, roughly, like four quarter pounders. And I know what a square inch is. IT JUST MAKES SENSE

You must hate inH2O for AOS then

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If you ever take fluid dynamics, imperial units get weird. If you would like to convert a slug to inches, rather than feet, you call it a blob. 12 blobs = 1 slug. I had a professor who made us use both imperial and metric units.

I was a throttleman on a nuclear power sub in a previous life, condenser vacuum was in inches of mercury....I understand it!

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Ohio?

USS George Washington Carver. It was a boomer out of Holy Lock Scotland when I was on it (89-91). I was a Navy Nuke Electrician. Was much better looking in my younger days.....let the pile on begin!

That's awesome Paul, thank you for your service. I'm actually an engineering analyst for the company that manufactures all of the bearing propulsion systems for the us navy's subs and large surface ships. I wrote simulations for a lot of the fluid mechanic theories at work. Getting more into the contracting and money side of things now though.

Wow, I just attempted the coolant fill this weekend also, only to find out my system would NOT draw vacuum down to 27. Could only get it to 22 or so. Guess I will have to put air into the system and check all my connections with soapy water....Dang. Nice right up, great pictures.

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Thank you for your service and your order! -Jason

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If it's holding the vacuum but not going any lower, your compressor is probably the culprit. If you can't move sufficient CFM @ whatever PSI the kit says to run at, you won't be able to pull as much vacuum.

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If you close the valve and it holds pressure for more than 120 seconds....don't worry about it and do the fill, yes, I agree it could be the compressor.

Thanks for the suggestion Paul and 5CHN3LL, I will give that a try.

Paul, nice work! Let me know when you want to take down that transaxle!

Paul, nice work! As a few have pointed out, a future project is to drop the transmission to see if the leak is RMS or other. If you do it at home, please let me know. I'd love to come down from Milwaukee to see it in action. Happy to bring tools. Glad to see you put those LNE parts to work. That was a fun day down at their shop. But the caravan from Chicago was something I won't forget! Tom