? about exhaust mount - PeachParts Mercedes-Benz Forum

Ether · #1 09-06-2007, 09:45 PM

On my 116 300SD I recently noticed a rattle coming from my exhaust. I found one of the rear rubber donuts had broken so I replaced it along with its mate but turns out that wasn't the issue.

Further investigation found 2 missing bolts on the horizontal arm on the pipe forward of the 1st muffler that attaches to the assembly adjacent to the transmission oil pan.

I've never paid much attention to this mount but it sure has my attention now!

It looks to me that 2 bolts attached this arm to the mount but they are now gone. Does anyone know the size of these bolts? I'm thinking I should be able to go to the hardware store and get the proper size and length bolts and nuts and be good to go.

Anybody ever had to deal with this issue?

Thanks

tangofox007 · #2 09-06-2007, 10:03 PM

You are probably missing more than just the bolts. This might be what you need:
http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=2650Q36L326A1B7IKT&year=1979&make=MB&model=300-SD-001&category=H&part=Exhaust+Mounting+Kit

Ether · #3 09-06-2007, 10:24 PM

I think you're probably right. The rubber grommets appear to still be there but the washers are gone and I'm guessing I'd have a tough time finding those inverted nut deals.

I had seen that kit but for some reason didn't put together in my noggin that it was what I needed. It's all clear to me now.

Thanks

spugeddy · #4 09-07-2007, 10:43 AM

I have an intermitant noise that is a rythmic clunking coming from the driver far rear, sounds like the muffler/exhaust area.

It happens once driving every few weeks, but once it starts it doesn't stop until I come off the go pedal, or stop. I have thought it was the muffler banging the underbody until today, when I was driving with it thumping, it sounded more like the noise was in tune with the rear wheel turning speed. IN other words it increased and decreased with the rotation of the wheel I thought. But coming off the pedal it would stop.

In my 45 minute commute I only heard it start the last 10 minutes...

Quote:

Originally Posted by Ether

On my 116 300SD I recently noticed a rattle coming from my exhaust. I found one of the rear rubber donuts had broken so I replaced it along with its mate but turns out that wasn't the issue.

Further investigation found 2 missing bolts on the horizontal arm on the pipe forward of the 1st muffler that attaches to the assembly adjacent to the transmission oil pan.

I've never paid much attention to this mount but it sure has my attention now!

It looks to me that 2 bolts attached this arm to the mount but they are now gone. Does anyone know the size of these bolts? I'm thinking I should be able to go to the hardware store and get the proper size and length bolts and nuts and be good to go.

Anybody ever had to deal with this issue?

Thanks

SD Blue · #5 09-07-2007, 11:00 AM

Spuggedy, sounds to be very suspicious of a flex disc. Check it out muy pronto. A friend of mine had one disintegrate and it wasn't pretty. Fortunately it was the rear but I couldn't imagine if the front one let go. I believe there are some pretty good photos in the DIY pages as to what to look for.

Tangofox007, do you happen to have a photo of what that mounting bracket looks like? A while back the subject came up about the exhaust bracket that mounts near the transmission. I believe it is completely missing on mine.

#6 09-07-2007, 11:07 AM

Quote:

Originally Posted by SD Blue

Spuggedy, sounds to be very suspicious of a flex disc. Check it out muy pronto. A friend of mine had one disintegrate and it wasn't pretty. Fortunately it was the rear but I couldn't imagine if the front one let go. I believe there are some pretty good photos in the DIY pages as to what to look for.

It could also be a CV joint, they also tend to start as a gradual noise. Is it worse when you are turning one way or the other?

spugeddy · #7 09-07-2007, 11:17 AM

not really associated with a turning sound.

I should emphasize I was driving 45 straight for 10 minutes and it was thumping as long as I was on the pedal, the instant I took off pressure or off all the way it stops.

But........ as I was turning left today, it sounded like a whell noise for a little during the turn, but then 100 yards later all the sound went away completley. I drove another 500 yards or so into work....

spugeddy · #8 10-25-2007, 10:10 AM

Noise just came back yesterday, it has been gone for awhile.

Not during turning, only when on go pedal, and stops when I come off pedal, worse at times, and at above 60 it kinda goes away. My muffler donuts look good, but I will prolly replaced them, and the flex disc looks new. I have looked at it several times and there is no visible cracks, damage, etc....

sound increases as I give it more fuel (rythmn speeds up)

I have checked the other ( I think there is two) metal hangers and they are tight.... should they be loose?

rrgrassi · #9 10-25-2007, 11:36 AM

Quote:

Originally Posted by spugeddy

Noise just came back yesterday, it has been gone for awhile.

Not during turning, only when on go pedal, and stops when I come off pedal, worse at times, and at above 60 it kinda goes away. My muffler donuts look good, but I will prolly replaced them, and the flex disc looks new. I have looked at it several times and there is no visible cracks, damage, etc....

sound increases as I give it more fuel (rythmn speeds up)

I have checked the other ( I think there is two) metal hangers and they are tight.... should they be loose?

Did you check the flex disks as advised? Also check the center support bearing and the cv joints, as advised.