Oil Leaks, they suck
 

Found a few drops on the garage floor about a week ago. Looked like oil. Got under the car, bunch of shit is wet. Did a bit of xoutpost searching, and got a few ideas of where to start looking.

So, I am leaking, looks like at the Vac pump. Half of it is covered in oil. When I say half, picture taking the vac pump and dunking half of it into oil like a you would a doughnut. Had a bunch of grime on it, so I think this issue presented itself much earlier, just not enough oil makes it down to the floor, especially when I am driving it every day. The past month it has been parked 4 out of 7 days a week, so I guess it had time to make it down to the floor.

I plan to order this kit and repair the sucker.
BMW 2004 745i Brake Booster Vacuum Pump Seal Kit 11 66 7 545 384

Notes for self:
-- for the 3x M6x25 torx bolts use 8 torx socket[listed previously] and torque this M6 bolts to 10 NM [from the factory they are torqued to 10.5NM] - Note : dry !
-- in order to turn the engine by hand [manually] by the main engine bolt - use 27mm 3" DEEP 6 point socket or 1-1/16 6pt deep socket - [the 12 points are to lose] .
-- also you will need 1x 20 mm O screw clamp to replace the original one on the hose from the vacuum pump ....

If anyone has a better suggestion, lets hear it. Now, if oil got into the brake vacuum system, what do I do to get it out?

I also pulled out the plug on the oil pressure switch, and it was full of oil. So ordering part number, 12618611273 Seems fairy self explanitary.

Notes for self: Note: [Oil and screw in] 24mm 6 points -- 3" deep socket ---- 20 Nm torque

My other issue, is what seems to be the friggen alternator bracket leak. I am a bit scared about this one. One guy I talked to, said subframe has to come off. A thread I saw on here, said the front diff has to come loose, and spun a bit, while the engine raised a bit. Is there a good how to for our cars about this problem. I was planning on tackling this myself. Thanks.

NOTES FOR SELF FROM OTHER PLACES.

After removing all of the aforementioned components air filter housing, fan, alternator, power steering pump, skid plate, etc., I pulled the right CV axle out, partially. The right axle assembly runs through the oil pan and is held in the diff with a spring clip E-clip at the end of the shaft. But with the tap of a hammer it'll snap out. There are several good videos on youtube that walk you through this process. With the right CV axle out of the diff you are able to pull the diff out away from the motor after you get it unbolted.

And here's where it gets a little hairy...3 of the 4 diff mounting bolts are easily removed, but the rear/top is almost inaccessible due to the contour of the diff housing, the motor mount and frame being in close proximity. However, it can be done with a little ingenuity. I started with a "pass-through" 16mm socket. These sockets do not snap onto a standard ratchet. They have a hex cut around the outside for use with a open/box-end wrench, giving them a smaller profile. I then put the socket on the grinder to scale the overall length down even more, to under an inch, leaving just enough of the outer hex to get a wrench on and just enough of the inner teeth to securely grab the head of the bolt. I could then reach up and slide my new socket onto the head of the bolt, accessing it from the bottom. With the socket on the head of the bolt, I could get my wrench on the hex end of the socket and break the bolt loose. Tip: break this hard-to-get-to bolt loose first. With the other 3 bolts still tight I was able to unthread this bolt with my finger tips, which is a must because you can only back it out so far with the socket on it before you get in a bind. So once you break it loose, take the socket off and unthread in with your fingers until it's completely out. Then you can remove the other 3 bolts. Now the diff is able to be moved out away from the engine and down just enough to give you access to ALL of the alternator bracket bolts. You might have to play with it a little, using a small pry bar to position the differential in the perfect location, but I was able to do this fairly easily.
The first alternator bracket bolt I tackled was the rear/lower one that the differential was blocking access to. I used the same modified socket and wrench configuration on this bolt as I did on the diff bolt. Once I broke that bolt loose I was able to unthread it with my fingers and the remaining bolts were a piece of cake.
And there you have it... Alternator bracket removed, $2,200 stays in your pocket, and a good beer is in order.

Nice job!!

I didn't do anything yet, just putting it all together in one post.

Planning ahead...makes for easier work.

Yea waiting on the parts. My vac pump is leaking like a pig. Well its weeping mostly, but still. Cleaned it all up yesterday. Went for a test drive. God damn, that is a serious leak. Seems to only do so after I drive.

I find it strange how my 12 year old Lexus never leaked anything.

Don't tell trader4 that, otherwise he'll come in and start ranting about how E53's are such pieces of shit.

GLW repairs Denis hope it gets sorted soon.

Yea ordered parts from Craig. So as soon as they come, going to bang out the vac pump and oil press switch in my garage. Then go to my friends place to use his lift for the alt bracket. I anticipate that being a supreme bitch.

Pay close attention how you mount the big O-ring. I f*cked it up the first try, and I thought all's good, but after the engine was shut down, there was a big pool of oil. At first I thought I installed incorrectly the VCG (This was part of the valve stem seals job). I really couldn't figure out where the leak was coming from... I suspected that oil pressure switch too. Every time I started the car, I couldn't see a leak...it was developing AFTER the engine was shut, but I was able to catch it.

Opened again the vac pump, and the big O-ring was sheared in 1/2. This because the 1st time I didn't bother to read the TIS - it looked a straightforward job. The problem was, when I tried to align the tongue in the groove (it was sitting almost flat), the 1st time, I had the VCG removed, and while positioning the tongue, somehow the O-ring went slightly off the groove.

The 2nd time I looked at the TIS, and you mentioned it correctly you need to have the groove vertical (by turning the engine - attention!!!!! very slow). The other piece advice from TIS is: make sure you use grease to hold the O-ring firmly in place, as it has the tendency to slip (as I found out the hard way). Those edges around that groove are sharp as a knife. You won't even feel that it will cut the O-ring to shreds, once it gets a little off.

I can't help you with the alt bracket, and I hope I will never have to do that job (fingers crossed while typing). But kudos to you for tackling it. Would be nice to have some pics of the modified socket....the brain can sometimes play games with one.

Cheers

Good info on the vac pump. Ty Doru.

I have an assortment of tools. So hopefully I will be able to get in there properly to get the diff off. We will see. Planning this about two weeks from now.

Heya Slick
Good luck.

When you have the vac pump out you might want to check the no return valve in the line going to brake booster. I believe it should allow suction to the pump but not air from the pump to "return" into brake booster. Original setup had vac line from pump to booster with non return valve on the connection to the booster (the 90 degree bend). When I replaced my vac tub I noticed BMW has updated to include a 2nd non return valve mid way from pump to booster too.

My vac pump had medium vacuum power and a small leak however that was enough for oil to escape/return (through worn out non return valve) into my booster. I found lots of recal info for the 4.8 in this regard but seems BMW did not include e53 4.8 in the mix. If caught early would save cost of brake booster replacement.

On oil pressure switch: sounds like you have seen the references to how that leaks more than vac pump o-ring. It's a 1 min job with vac pump out of the way.

Thanks for your post with notes on the diff removal steps. I'm really interested to hear your feedback on how this goes without lifting motor and removing motor mount.

LOL
:bustingup

Well time for an update.

I guess 9 year old car, shit starts to leak.

So it was not the alternator bracket, at least that is not what I am thinking now. I went through like 10 cans of break clean to get to that conclusion.

I did the BMP kit for the vac pump, so that leak is gone. I also replaced the oil pressure switch, not sure for what reason, but I had it on me, and figured why the hell not. For $14 not worth the hassle of returning it. Did my front diff fluid while the skid plate was off.

After cleaning up the 9 years of crud, I started the car on the lift, and ran it for a while.

We found the possible leak that was making me think the alternator bracket was messed up. It was coming from the two power steering hoses coming off cooler. Both of the quick connects are deff leaking. I was finally able to see green fluid coming out of them since everything is now clean. I guess driving around, the fluid was getting tossed back, and making my alternator bracket be the pit stop.

So part 2 starts soon, just need to order the new lines. I have the reservoir already, so my truck is going to get some new stuff shortly.

Special plug for my friend who owns OMG Motorsport in Long Island for letting me use his lift, and his supplies, and a second pair of eyes for half a day, for a super super low friendly price.

Facebook page, because you can see my car there. lol.
https://www.facebook.com/OMGmotorsports