1998 540 v8 exhaust welding question

[Eriklane]

I recently had my 1998 BMW 540I V8 in because I had some vibration in the middle of the car upon acceleration. I had a mechanic look at it and he seemed to think it was the center support/bearing and that was all replaced, along with the guibo.


The mechanic indicated that the driver side exhaust hanger that attaches to the center support steel panel(that bolts to the bottom of the car) was rusted off and thus he could not fix that. I will attempt to create a support for that, but have a question. I figure that the exhaust is stainless, and the heavy flange material that was factory welded to the top of the exhaust pipe is also stainless. Since I have no tig welder, and only a stick arc welder and a small harbor freight wire feed welder, I surmise that I can't fix weld on a new flange to the existing metal. Correct? It should be tig welded?
Another solution is for me to get some heavy sheet metal and form a support flange, and then simply clamp it to the exhaust pipe, which is probably where this is going. It's fairly simple to do and involves no welding. I'd like it done right, but it'll be $100 for a muffler shop likely to touch it...thoughts?

Also, assuming I do the clamp method myself, is there a gap between the support metal and the exhaust pipes? I would think there is one, which now is why I'm getting some noise as the pipes are laying on that metal...

Actually found a pic and think it sort of answers both questions...apparently the driver side(left) in the pic almost seems to have the hanger added by strapping it to the pipe. No idea, but also found some other pics that seem to show only 1 hanger, so not sure if this person added it or not, but it almost appears so. Also, notice the rubbers are open, mine is crushed down, which makes me think that the reason mine is that way is because the entire exhaust is low, and laying on that metal brace. I will attempt to find a strap like shown, figure out why the exhaust is low(maybe the rubber is original and it's simply flabby and lost any lift it had. Will repost once I get to this, which won't be immediate...

[Eriklane]

not sure what happened-here's the original text:

I recently had my 1998 BMW 540I V8 in because I had some vibration in the middle of the car upon acceleration. I had a mechanic look at it and he seemed to think it was the center support/bearing and that was all replaced, along with the guibo.


The mechanic indicated that the driver side exhaust hanger that attaches to the center support steel panel(that bolts to the bottom of the car) was rusted off and thus he could not fix that. I will attempt to create a support for that, but have a question. I figure that the exhaust is stainless, and the heavy flange material that was factory welded to the top of the exhaust pipe is also stainless. Since I have no tig welder, and only a stick arc welder and a small harbor freight wire feed welder, I surmise that I can't fix weld on a new flange to the existing metal. Correct? It should be tig welded?
Another solution is for me to get some heavy sheet metal and form a support flange, and then simply clamp it to the exhaust pipe, which is probably where this is going. It's fairly simple to do and involves no welding. I'd like it done right, but it'll be $100 for a muffler shop likely to touch it...thoughts?

Also, assuming I do the clamp method myself, is there a gap between the support metal and the exhaust pipes? I would think there is one, which now is why I'm getting some noise as the pipes are laying on that metal...

Actually found a pic and think it sort of answers both questions...apparently the driver side(left) in the pic almost seems to have the hanger added by strapping it to the pipe. No idea, but also found some other pics that seem to show only 1 hanger, so not sure if this person added it or not, but it almost appears so. Also, notice the rubbers are open, mine is crushed down, which makes me think that the reason mine is that way is because the entire exhaust is low, and laying on that metal brace. I will attempt to find a strap like shown, figure out why the exhaust is low(maybe the rubber is original and it's simply flabby and lost any lift it had. Will repost once I get to this, which won't be immediate...

[CPHES]

Can a mod delete the first post?

[BimmrMeUpSnotty]

Jeeesus! That post went haywire!

[JimLev]

Yup, not the correct way to post a pic.
Eriklane, is your car an iT (wagon)? If not I'll move this post to the correct section.

Here's the easiest way to post a pic.

Post a pic_1.JPG

Post a pic_2.JPG

[Eriklane]

Sorry its not a wagon

[JimLev]

Post a pic of what you were asking.

Part #3?
https://www.realoem.com/bmw/enUS/sho...diagId=18_0258

[philly98540]

I like the clamp on solution due to your welding equipment and rust. Will need some fabrication skill to get it close enough to work good but definitely doable. There is a rubber mount that mounts it to the metal cross support plate. The pipe sits just above the support plate.

[Eriklane]

exhaust hangers.jpg

Sorry for the hassles guys, and thanks. The OEM diagram shows 1 hanger on the driver (US Left) side, and the pic is looking back, and shows the clamped on deal apparently added to the passenger side. My solution is to buy a 1" or 1.5" piece of mild steel that can be bend by hand, and I'll form a circle and have it extend out far enough to reach a drilled hole in the steel, and then I'll also have a bolt tightening the steel like shown in the pic. Or should I use stainless ? Will Steel and Aluminum react? I bet they will. The joys of cars...OR...the fact that my pipes are resting on the support, and the hanger is quite crushed - is that the issue-maybe the hanger is toast, it's probably factory and has lost its lift maybe...

OR I could go with a stainless U bolt type clamp and attach a piece of flat stainless stock that's drilled to it- Can stainless be bent or drilled? I need 3 holes, but maybe flat is good, it may line up ok, but if I need to bend it a little, is that even possible?

[JimLev]

Sure stainless can be bent and drilled. Get a cobalt bit, use oil, and drill at a slower speed.
My 540 only has one rubber support on the drivers side.