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Clarksonvalley
10-11-2015, 11:20 AM
Attached is a photo of the engine mount I replaced (on the left) and a new mount (on the right). Notice the top attachment bolt and plate are missing on the old mount. A valve cover oil leak saturated the mount softening it enough for the top metal attachment of the mount to separate from the rubber - result is a lot of banging noises when I drove over bumps as the mount tried to hammer itself to death.

http://www.bimmernut.com/forum/attachment.php?attachmentid=8351&stc=1

There is a recess in the rubber surrounding the top attachment point that fills up with the leaked oil thus hastening the failure - I filled the recess on the new mount with black silicon to help prevent a similar failure in the future. Next project is to replace the valve cover gaskets for both cylinder banks. Question - should the rubber valve cover gaskets be installed dry or with a gasket compound? I have used Permatex 'Aviation Form-a-Gasket' in the past on paper gaskets, but never on rubber gaskets. The Form-a-Gasket never hardens like RTV or other silicon products. Any thoughts anyone? Also, has anyone ever used a 'auto detailing' service to remove all of the oil and crud from their engine? Doing it by hand with Simple Green or a grease remover is a lot of grief.

632 Regal
10-11-2015, 12:01 PM
On the gaskets I used permatex spray tack and a little RTV only in the areas with sharp changes in direction, I'll see if I can find a picture.

This is overkill, only need a little dab on the sharp corners: http://blog.bavauto.com/wp-content/uploads/2012/09/fig10.jpg

The spray tack helps hold things in place while trying to replace the cover, no other reason for me.
My motor mount was swollen from power steering juice. How hard was it to loosen the top bolt? When I tried my 6 foot of extensions were twisting badly, thought they were going to break so I have new mounts sitting next to my desk.

Clarksonvalley
10-11-2015, 01:21 PM
I also had problems with power steering fluid leaks. I finally gave up with the BMW piping arrangement. I bought a new steering fluid cooler, cut off both tubing bead ends and brazed on Earl's threaded fittings. I got rid of the intermediate steel tubing (part no. 32 41 1 141 530) that is secured to the inside of the left front fender wheel well and ran two continuous pieces of Earl's 'Super Stock' reinforced rubber tubing with Earl's threaded end fittings from the cooler, one to the plastic reservoir where I had to use a hose clamp another to the steering pump where I used an Earl's fitting. This system eliminated (7) hose clamp fittings (eliminated (4) hose clamps by removing the intermediate steel tubing) leaving only (1) hose clamp at the plastic reservoir - this hose clamp fitting still weeps fluid, the Earl's fittings are totally leak free.

632 Regal
10-11-2015, 04:19 PM
From as much as I can see the hoses are not the culprit in my situation but most likely the bottom seal. I added a bunch of stop leak that has slowed it down a lot but it seems to leak more in winter. I hope this seal stuff doesn't blow something in winter because it is very thick, like gear lube.

shogun
10-11-2015, 06:33 PM
If the engine mounts were so bad, that also has affected other mounts, as the engine turned more with accelerating and decelerating. Check also transmission mounts and also the center bearing of the driveshaft and also the giubo.
More moving of the engine can also cause the known cracks on the connections of the radiator. Radiator is fixed mounted on the chassis, engine is moving.

Clarksonvalley
10-11-2015, 08:01 PM
Does anyone have any experience in using an auto detailer to de-grease the engine bay plus the underside of the engine/gearbox?

mattyb
10-13-2015, 08:36 AM
I've changed mounts twice on the 540s I've had, the left side was the precursor for doing this, it was the power steering res that was the prob both times. regarding a suitable cleaner I used a medium solution of caustic, 1 part caustic to 20 parts water, brushed on , atomiser bottle is ok, left to sit 5 minutes then neutralized liberally with white vinegar then warm soapy water to finish. auto detailers seem to like high pressure hoses etc which I consider a problem causer on any vehicle. I was fortunate to have high ramps so I could get under the vehicle to do so. I was also to engineer a tool for the left mount, it was just an open ended spanner cut down to about 3 inch, which held the nut in place against the railing so I needed to only concentrate on moving stuff from under neath in most cases. I have never needed to use the endless extension method. I will post pics of the tool when I can and am more than happy to make a couple and send to you guys if you can get enough room under the car to use it . I've got this job down to 10 minutes a side these days, including a beer or two along the way, as it is a 540 thing. in fact im sure I posted some pics some years ago the first time I did it.
regarding the caustic method wear PPE glasses when u do it and always have the vinegar available before mixing and using the caustic for your own safety. id love to see the photos of the alternate hose arrangement you have described Clarkson so I can do same.

regards
MattyB

Clarksonvalley
10-13-2015, 03:14 PM
mattyb,

I'll see if I can get some photos. The problem is - I had to remove the front bumper and left hand headlight assembly to get access to the hoses. The intermediate steel tubing I mentioned I removed is secured to the inside of the left hand fender well by a 10 mm bolt - also not easy to access. I think I may try the local DIY car wash to get some of the gunk off. I've been chasing a problem that I have not found yet - a banging noise at the left hand front suspension. The left front shock was bad - replaced both front shocks - Bilstein Sport shocks - also replaced both front tie rods (torn rubber) and both front sway bar drop links (also torn rubber). Banging noise is still there. I suspect the ring nut at the top of the Bilstein shock has loosened allowing the shock to move up and down in the strut tube, but I tightened the ring nut as best I could with a rubber strap wrench - it is supposed to be tightened to 45 lb. ft. with a special Bilstein torque wrench, but I don't have this tool. I doubt that I have it tightened to 45 lb. ft. I've also looked at the attachment of the front subframe to the frame - appears tight. I stumped on the banging noise.