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Alternator Bracket Gasket leak

14K views 34 replies 13 participants last post by  HerbP 
#1 · (Edited)
So I took my car in today to get the gasket replaced, I found an independent that some other friends have used for their BMW's who quoted me $450 to replace. If I had to pay $1200 I would do it myself, but for that price I am more than happy to not spend 9 hours bent over my car...and crawling under it. I currently have 60,000 miles so it is the right time for oil leaks from what I have read. Whereas my 2000 Jeep Wrangler with 109k miles never leaks a drop, and all my friends with Lexus/Escalades/NSX/Mercedes that have similar year and mileage don't leak. Go BMW quality! I still love my car though. :thumbup:

Some other independents quoted me the book time of 8 hours, from $1000 to $1200. But these guys have done it before and said they know they can do it in 5 hours, which I have read shady-tree mechanics saying it takes 5 hours when they have done it more than once. I am just happy to find someone who charges real time and not book time.

So here is an interesting part, the guy called me to tell me I have an oil cooler. As has been documented, it seems most cars do not have them and the alternator bracket acts as a block-off plate. So if I have an oil cooler, which should reduce the breakdown in my oil because it reduces the high operating temperatures, why do my seals still go bad so quickly? This shop which specializes in German cars says that BMW use crappy seals and are known to leak (newsflash threre? I think not!). I asked if more frequent oil changes will rectify that since it has been discussed on the board as the culprit to failing seals. He told me that the folks who he services and get frequent oil changes still have leaky seals, so that doesn't help the matter at all. However he did recommend 10k oil changes for overall engine health, but not for increased life of the seals.

Here is what my garage looks like after one night, this cardboard cutout is 3 feet x 4 feet, so it gives you perspective what is going on. Just an unacceptable situation to see this leak every day!!! Despite this going on for the last month I have not had a low oil warning and when I check it the level is fine. I am crossing my fingers that nothing unexpected comes up from the mechanic. :eeps:

 

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#5 ·
I have done it on my 645 & 750. The 645 is around a 8 hour job, & the 750 is around a 6 hour job. The 750 has a lot more room under the hood! So why do our gaskets & seals fail so fast? It has to be oil related, & poor quality seals & gaskets! You warranty a car on the front end, knowing you will make it back on the aging of the car. If you do not have a extended warranty on a BMW, you better have deep pockets, or know how to turn a lot of wrenches! It is a documented fact, the seals & gaskets are going to fail!

Has anyone had any success with any other gasket brands available aftermarket? I am getting ready to have to change my valve cover gaskets on my 750, with 64000 miles. I have already done the alternator bracket, & I add an extra layer of RTV for a better seal. I am not taking any chances of replacing it again.

My rant is now over!:mad::mad::mad::mad::mad::mad:

Next!
 
#6 ·
If you do not have a extended warranty on a BMW, you better have deep pockets, or know how to turn a lot of wrenches! It is a documented fact, the seals & gaskets are going to fail!

Has anyone had any success with any other gasket brands available aftermarket? I am getting ready to have to change my valve cover gaskets on my 750, with 64000 miles. I have already done the alternator bracket, & I add an extra layer of RTV for a better seal. I am not taking any chances of replacing it again.

My rant is now over!:mad::mad::mad::mad::mad::mad:

Next!
I don't know if there are aftermarket alternatives. The problem with the extended warranties is that most of the time leaks and seals are excluded. Oh well, it is what it is!!! :dunno:
 
#10 ·
Quick note auto-Pom covers gaskets... Currently replacing alternator bracket, upper timing and valve cover. Apparently all went bad about the same time which isn't a surprise
You are correct, that is not a surprise! That is great news, is that the Platinum Coverage?

I bought my car with 1 year of full warranty and then 2 years of CPO. I had several common items fixed during that time but elected to forgo any additional aftermarket warranty. If I can keep my repairs fairly infrequent and a minor cost like this I am all good!

One indie I spoke to advised me that I should replace the upper timing and valve cover since they all go within the same timeframe. But the guy I went with pointed out that the bracket gasket is under pressure and very difficult to ignore because of the volume of oil it leaks. Whereas the covers just will seep a bit and take longer to become problematic.

Thanks for the information Mark. I guess that these leaks are inevitable even with frequent oil changes. Can't believe that it is the poor quality of the gaskets and seals.

Luckily, I'm at 64k miles right now and haven't had a leak yet, although I have AutoPOM handy should an issue arise.
Forgot to mention that $450 is a great deal for the repair.
At least you can have confidence that increasing the frequency is all around better for your car! Maybe it won't save the seals, perhaps it will keep them healthy a little bit longer? So hard to tell.

My leak came on all of a sudden, the oil is under pressure at that point so the leak is way more noticeable than valve covers.
 
#8 ·
Thanks for the information Mark. I guess that these leaks are inevitable even with frequent oil changes. Can't believe that it is the poor quality of the gaskets and seals.

Luckily, I'm at 64k miles right now and haven't had a leak yet, although I have AutoPOM handy should an issue arise.

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#13 ·
Timing Cover Leaks

The Upper Timing covers can leak pretty bad on these engines as they are under pressure as well. There is oil hole on passenger side for oil to the vacuum pump on drivers side this hole is blocked by gasket the rubber stops sealing good after a while and u can get a pretty fast oil leak there. Randy
 
#15 ·
I always add a little gray silicone around the outside of the o-ring. Do not allow any to get in the oil system, allowing it to plug up a oil port. Make sure you torque the bolts to make sure there is a tight flush fit. I replace my original bolts with hex head bolts, to get a better torque.
 
#17 ·
I'm right in the middle of doing this too, I just got the power steering pump off. Next up is the oil cooler, engine support, then the bracket. Herb, where can I get the replacement hex bolts? Do you have a part number?
Also, I don't want to start another thread to ask a simple question so I'll just ask it here. Does the alternator bracket have to be off to replace the upper timing gasket? Just looking at it, it looks like it's in the way of removing the timing cover.
 
#18 ·
You can get the bolts from a local bolt store, or auto parts warehouse. Make sure to get the proper length, & bolt grade. Bolt stores will also be cheaper, & will always give you the proper grade bolt. The upper timing cover plate can be removed with the alternator bracket on. You can also replace the gasket with the valve cover on, as long as you carefully raise the front of the valve cover. Loosen the front bolts on the valve cover, & slide the timing cover out.
 
#22 ·
So I'm down to the T45 bolt and I'd have the bracket out, but just my luck it looks like it's stripped. What do you guys think? Does it still have enough "teeth" to come off? I don't want to try again until I get some feedback. Any Ideas what to do it it is stripped? Does it matter that I'm taking it off last? Will it help if I put some of the other bolts back to relieve some tension? I just soaked it with penetrating oil while I ponder what to do next.
 

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#23 ·
I would try a new socket 1st, then a bolt extractor socket next. If that does not work, drill the head off & remove the bolt once the cover is out. You could also try tapping the socket with a hammer, to see if it will help break it loose. The bolts only have around 10 nm torque, so it should not be stuck.
 
#27 ·
If the mount looks ok, it should be good to go. You don't ever really hear about a failed mount. I never noticed that there is a thermostat built into the oil cooler line, but I have never heard about that failing either. It should not be a major problem to get either one of these off if they fail.
 
#28 ·
Tampa Mark I live in Tampa. My 645 doesn't have an oil cooler. I had Twilight auto replace my gasket 7 hours $80 an hour. Leak stopped. I did replace the upper timing chain cover and valve cover gaskets on both sides, that's a pain too, but not as bad as the alternator bracket gasket
 
#31 ·
I spoke with them a couple of years ago, I wish I had used them after reading your post. I went with a BMW indie off Anderson and it was a disaster. They replaced the gasket, but it was leaking afterwards, confronted them and they said it was the Timing/Valve cover leak.
 
#29 ·
OK, I'm getting ready to button this up. I opted not to replace the mount and oil cooler thermostat. I've searched but could not find the torque specs for the Alt bracket to engine block, and the mount bracket to block. Does anyone know? I just have the hand tightened for now.

Also, I haven't seen this noted anywhere but the Alt bracket has these 3 "washers" that pinch it to the block. It is hex shaped inside and you can use an allen to move them in and out. It will make it easier to remove the bracket from the block if you screw them towards the bracket first when taking off. When putting back, put the bolts through the holes just to make sure the holes line up, remove bolts, use the allen to screw the washers out and tighten against the block before putting the bolts back in.
 

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#33 ·
That is correct. I use a 1/4" torque wrench just to be safe on these. You still have more fun waiting on you!

11 14 Case Covers
Type Thread Tightening specification Measure

1AZ Timing case and timing case cover top and bottom

M6 10 Nm
M7 15 Nm
M8 22 Nm
M10 47 Nm
 
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