Rear Oil Pan Bolts

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528i-1981
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Joined: Wed Feb 07, 2018 5:50 am
Location: Boston, MA

Rear Oil Pan Bolts

Post by 528i-1981 »

Gents:

I noticed an annoying leak from the oil pan gasket, annoying because it was replaced less than 3000 miles ago in 2019. Some of the bolts were torqued below spec. I can't get to one bolt at the rear which is recessed and the bell housing has an annoying little ridge so a socket cannot pass. The recess isn't wide enough for lateral access to the bolt head with a wrench.

I'm sure someone has faced this before. Is my choice between a major ordeal or leaving this bolt as a torque-orphan? Or is there a magic zero-width zero-height zero-depth tool that can apply 8 ft-lbs? Bonus if this magic tool can do this without jacking up the car and with me inside on the couch.

Thanks!
(oo=00=oo) Eric
1981 528i Manual
canada karl
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Re: Rear Oil Pan Bolts

Post by canada karl »

Have you tried a 1/4" drive ratchet with a long extension? A thinner walled socket might help with the recess issue. I am having a similar issue with a leak at an auto trans oil pan bolt. At first I thought it was the rubber pan gasket so I changed it out and it was still leaking at the corner bolt. I suspect a warped oil pan at the bolt from over tightening by the PO. I tried RV on and near the bolt with no luck. Thing is when I tried to remove the oil pan the filler tube prevented me from removing the pan completely because the filler tube is held by a bracket attached to a large trans housing bolt. Now not only is this bolt hard to get at from under the hood but it looks like it could not be removed because it would hit the firewall?
I was able to change out the gasket without removing the pan but just by lowering it with the bolts out. But now I have to take the pan off completely to straighten the warp at the corner bolt and maybe seal the bolt threads there. To remove the pan I could disconnect the large filler tube cap nut at the pan itself but it looks like I could bend the pan by wrenching on that cap nut?
Wonder if anyone on this forum who has worked on a ZF auto has any advice?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
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528i-1981
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Location: Boston, MA

Re: Rear Oil Pan Bolts

Post by 528i-1981 »

Following up for posterity - a 1/4" drive thin-walled 10mm socket can access the rear oil pan bolt.
Last edited by 528i-1981 on Sun Sep 19, 2021 6:52 am, edited 1 time in total.
(oo=00=oo) Eric
1981 528i Manual
canada karl
Posts: 923
Joined: Tue Jan 06, 2009 3:50 pm

Re: Rear Oil Pan Bolts

Post by canada karl »

Hi Eric Are there still a few E12's on the road in the Boston area? How about at the wreckers?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
canada karl
Posts: 923
Joined: Tue Jan 06, 2009 3:50 pm

Re: Rear Oil Pan Bolts

Post by canada karl »

Hi Eric Are there still a few E12's on the road in the Boston area? How about at the wreckers?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car
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528i-1981
Posts: 441
Joined: Wed Feb 07, 2018 5:50 am
Location: Boston, MA

Re: Rear Oil Pan Bolts

Post by 528i-1981 »

Hi Carl - Other than Joe Boston, I know of zero E12s on the road up here. I've seen only one over the years, a 530i in Connecticut that was obviously still be driven as a daily or nearly so. When I saw it it, an older woman was behind the wheel. I assume the road salt has done its part to thin the herd up near you as well? None of the junk yards I've talked to have them anymore. There is one in Lunenberg, MA that has a few things on racks, but the cars themselves have long since been sent to the crushers.
(oo=00=oo) Eric
1981 528i Manual
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Joe Boston
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Re: Rear Oil Pan Bolts

Post by Joe Boston »

Eric, today I saw a another 1981 E12 White alpine, in Mass in very good condition. he bought it in Cali not to long ago..
so far total of 3 E12 left..

Joe
1980 E12 Ascatgrau 5 speed
2001 E38 740 Black
2012 F12 650 IC black
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528i-1981
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Re: Rear Oil Pan Bolts

Post by 528i-1981 »

Hey Joe - nice to hear from you and great news about the E12. Is Naomi back on the road? I think the last pix I saw were from last fall during the repaint and rear axle rehab with the LSD.
(oo=00=oo) Eric
1981 528i Manual
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