Advice on A Class A 160 Rear Exhaust ?

Submariner1

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CL500 2009 5.5
The exhaust passed the Recent MOT test.
But the long pipe is well corroded, and the big rear box, has perforated the outer skin in 3 places. It was not leaking but I slapped £6s worth of gun gum on the offending places.

Grangemouth do a great deal £114 incl vat. So rather than have the pipe snap, and an irate wife with the exhaust jackknifed into the floor pan ... I don't mind changing it.

Q1. Does the car have to be level when you screw up the compression olive like fitting?
Access for me would be easiest with passenger side jacked up and supported with axle stands. But that puts the 2 centre rubber hangers at a slant. If I lock up the compression joint, effectively A bit twisted, that doesn't sound clever. I.e. Putting strain on the Cat Box’s flange, which is in excellent condition with only 60K on the clock, and zero rust (I assume that is stainless).

my thoughts were ...
Get the exhaust all installed on the rubber hangers, but with the compression joint Bolted secured but loose, i.e. it can rotate with the car on a slant.
Then lower the left front and jack up the right rear. So the car is then pointing downward at the front but at least level Side to Side. Then torque up the joint where the weight of the box is not twisted on the CAT box flange.

Q2. The 3 rubber hangers look fine, but are 2002 age? Attaching the spigots on the Exhaust box looks easy, but pushing the rubbers completely off the centre support hangers would hit the heavy duty under-panels, not up for removing them.
The actual hangers that screws into the floorpan Is a one bolt affair.
Will these come out easily, or would be it be likely that I hit corrosion issues.
Any tips ... is it easier to unbolt the hanger and put on new rubbers and then bolt the hangers to the car with the exhaust. Or easier to unbolt hanger and replace rubber , secure hanger to car With the Rubbers and then push on the rubbers over the exhaust spigots as you raise up the exhaust?

And without a torque value does one just use a general torque value for M8 to bolt these hangers into the bodywork? Oddly no value in WIS. Where it does state 22Nm for the Olive joint.

rusted through outer skin near MB box support strap ( daft idea )
59DA9935-6002-4C17-A57E-50492EEE4A53.jpeg
Amazingly it doesnt blow
F55A7708-AF8A-44D5-A0A5-BFA134642294.jpeg B5D21829-5A7B-41C5-880B-641E555AE6CE.jpeg
wasted time scraping off loose rust and Gun Gummed ... still not set hard 2nd day and idled for 1/2 an hour???
AF446CFD-AFF9-4F1C-9D24-A9DE66EB2865.jpeg
These are the 2 hangers with one bolt into the body? Not enough clearance to push off the rubber at the bodywork side.
8C09F2F7-A8FE-48F0-94CF-28EFACB754D1.jpeg

Just wondered if anyone had done an A-Class? Seems daft, but My fear is the securing thread in the bodywork is toast and I can’t support the new exhaust. Then I am stranded lol.

Do these Olive “donut” compression joints undo easily? Doesn't seem to have any sealing compound.
I have sprayed good penetrating oil on the joint and will leave a couple of days.
 
Last edited:

Flyinspanner

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Hi
I did the exhaust on our W168 a couple of years ago.
It is pretty easy.
(I did have to cut one of the bolts on the compression joint) and elected to use two new bolts.

Don’t think the olive on the joint had any goo, but I wiped a bit on when replacing, probably doesn’t really need it.

The rubber hangars, looked all intact so I just lubed with silicon spray and pulled exhaust out - pushed new on in, its still fine :rolleyes:

I think I popped it up on 4 axle stands to give me room under to work.

The hardest bit was cutting the bolt (angle grinder) without damaging the collar.
I would happily re do it. - got the whole exhaust from Germany £57 off eBay, though I now can hear a baffle rattling in the rear box :mad: so 114 is worth it for a fit n forget :geek:.
 
OP
Submariner1

Submariner1

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  • Thread Starter
  • Thread starter
  • #3
Hi
I did the exhaust on our W168 a couple of years ago.
It is pretty easy.
(I did have to cut one of the bolts on the compression joint) and elected to use two new bolts.

Don’t think the olive on the joint had any goo, but I wiped a bit on when replacing, probably doesn’t really need it.

The rubber hangars, looked all intact so I just lubed with silicon spray and pulled exhaust out - pushed new on in, its still fine :rolleyes:

I think I popped it up on 4 axle stands to give me room under to work.

The hardest bit was cutting the bolt (angle grinder) without damaging the collar.
I would happily re do it. - got the whole exhaust from Germany £57 off eBay, though I now can hear a baffle rattling in the rear box :mad: so 114 is worth it for a fit n forget :geek:.
Thanks
Good to know they are no real pitfalls.
I wire brushed the 2 bolts they came up pretty clean so hopefully will undo. Like you I would put in new ones .
Dosed them with penetrating oil and might repeat a few days before the job.
 

LostKiwi

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Best thing for exhaust goo is high temperature silicon. Flexible, seals well and allows dismantling again.
 


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