Exhaust heat shield & floor pan holes

[jeffc280sl]

I have replaced the pass floor pan and I'm in the process of reinstalling the longer exhaust heat shield.  Mine was secured by sheet metal screws fron underneath.  The threaded part of the screw came up through the floor.  I doubt this is how the factory mounted the exhaust shield.

Can anyone advise how the heat shield is secured to the floor?  I don't want a rattle later on and would like to do this job once.

Also on the floor under the pass seat, just in front of the rear inner seat bracket, there are two holes in the floor pan.  One looks like it is countersunk.  They seem to be along the same line as the exhaust system.  Does anyone know the purpose of these holes?  They do not appear to be part of the exhaust suspension and they are to the rear of the heat shield I talk about above.

Many thanks,

Jeff C.
1970 280SL 4-speed

[Jonny B]

I just went out and looked at my car, and the screws for the exhaust heat shield under the passenger floor appear to be screwed into the metal. I will be curious to see what others have to type on this one.

I cannot help on the other question.

Jonny B
1967 250SL Auto

[TheEngineer]

Sheet metal screws on mine

[jeffc280sl]

Thanks for the info.

I read where the screws become loose over time and the shield rattles.  I suppose the prior owner just installed a larger sheet metal screw.  It was also longer and stuck up into the floor too far.  I decided to used nuts and bolts to secure the heat shield.  I used the same size as those on the drivers side floor that hold the brackets to secure the fuel and brake lines.



Jeff C.
1970 280SL 4-speed

[Vince Canepa]

For the long heat shield, the screws come up from the bottom.  They project through the floor a bit on the inside.  I noticed this some 30 years ago on mine and cut short pieces of rubber tubing which I placed over the pointed ends.  I also put a drop of Loctite on the screws to keep them from backing out.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[TheEngineer]

Nuts & bolts is a good repair. Better than new. My compliments!