Gas leak question

Post your E12 technical questions and comments here. Please, no off-topic posts.

Moderators: Mike W., Pierre

PatinaBeforePolish
Posts: 264
Joined: Sun Jan 18, 2015 1:22 pm
Location: Baltimore, Md.

Post by PatinaBeforePolish » Fri Nov 03, 2017 10:49 am

cory58 wrote:
PatinaBeforePolish wrote:I know this is a simple suggestion, but have you rotated the engagement side of the clamp to the low side? Are you installing the cover upside down?
Thank you. No offense taken! When you're knee-deep in a problem, sometimes it's hard to see the big picture and simple things get missed. I'm definitely not putting the cover on upside down, because the seal is facing down.

I'm not sure what you mean about the hose clamp. When the worm gear body is parallel with the trunk floor, the screw head is facing away from the return line. I've rotated it to the right as far as it will go, which puts the screw head facing up at about 12:30, and rotated it to the left as far as possible that still allows me to get a wrench on it, which puts the head at about 8:00. One thing I did not do is remove the clamp and turn it around so that the screw head is facing the return line, because I did not think that would make a difference.

I'm doing something wrong, but have not figured it out yet. Frustrating, after getting the new tank in relatively easily.

Thanks, Cory
I was referring to the worm gear oriented on the low side, opposite of the cover. Have you measured the height of the fittings on the old tank vs. the new one? I guess you could shim where the tank bolts to the frame with a thick washer if it's off by just a few millimeters.
78 F150
79 528i
01 540i
86 944
08 X3 don’t judge me it’s there to preserve the others

cory58
Posts: 109
Joined: Thu Aug 25, 2016 8:49 pm
Location: Charlotte, NC

Post by cory58 » Fri Nov 03, 2017 2:03 pm

PatinaBeforePolish wrote: I was referring to the worm gear oriented on the low side, opposite of the cover. Have you measured the height of the fittings on the old tank vs. the new one? I guess you could shim where the tank bolts to the frame with a thick washer if it's off by just a few millimeters.
Now I understand! Thank you. The clearance under the fitting is barely enough to slide the clamp in and out, so the worm gear definitely won't fit under there. It was the same on the old tank fitting.

I plan to spend some more time with it this weekend and will report back. I will measure the fittings. The replacement tank is from an early (E12 based) E24 and I noticed it's not exactly the same. I'm wondering if the inset for the sending unit is not as deep as on an E12 tank. Will check that out also.

Thanks for your help.

Cory
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2015 328i (wife's car)
2001 325i (R.I.P., still missed)

T.Hanson
Posts: 1696
Joined: Wed Jul 26, 2006 7:39 am

Post by T.Hanson » Sun Nov 05, 2017 12:42 am

I admit reading your posts waiting for success. That said, the reference to using a non-stock tank, with a," WORM GEAR ? "

Boy am I out in left field.

cory58
Posts: 109
Joined: Thu Aug 25, 2016 8:49 pm
Location: Charlotte, NC

Post by cory58 » Mon Nov 06, 2017 9:33 am

Duh! It was user error as I suspected. The small end of the hose clamp that's under the worm gear was hanging up on the hose and preventing it from rotating all the way. Once I got it rotated as far as possible, the cover would fit.

Car is finally back on the road. Took first drive since June. Awesome!

As soon as I have time, I will post a more thorough rundown of my experience changing the tank, including pics of the differences between the E24 and E12 tanks.

Thanks for all the responses.

Cory
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2015 328i (wife's car)
2001 325i (R.I.P., still missed)

LandShark
Posts: 10
Joined: Thu Jan 09, 2014 3:49 am
Location: ABQ NM

Post by LandShark » Fri Dec 08, 2017 11:11 am

Similiar tank and similiar tech on my e12 based e24. I recently changed all evap and pump hoses, o rings. And she still leaks when I fill up with more than 8 gallons. Middle tank seams can definitely weap even when it passed pressure check (with my lungs).
76' 633 CSi

User avatar
Mike W.
Posts: 2451
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. » Fri Dec 08, 2017 1:23 pm

LandShark wrote:Similiar tank and similiar tech on my e12 based e24. I recently changed all evap and pump hoses, o rings. And she still leaks when I fill up with more than 8 gallons. Middle tank seams can definitely weap even when it passed pressure check (with my lungs).
Not common, at least on the west coast, but yes they can. I hear it's a problem on 2002s and I had that on a Bavaria way back when. And yes, that seam is where they typically leak.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

cory58
Posts: 109
Joined: Thu Aug 25, 2016 8:49 pm
Location: Charlotte, NC

Post by cory58 » Fri Dec 08, 2017 1:58 pm

Mine was also leaking when I put in more than 6-8 gallons. No rust anywhere on the bottom of the car, but the filler neck had rusted where it meets the tank.
1977 530i
1988 320i Touring (euro)
1992 325i Cabrio
2015 328i (wife's car)
2001 325i (R.I.P., still missed)

Post Reply