1975 450sl newbie....a couple questions
 

Hi,
I recently purchased a 1975 450sl....fairly high mileage (200k)
but it an Arizona car, runs strong, and has impeccable records. There are 2 items I have questions about.

1. it seems to have a leaky fuel injector. I have ordered a new injector and o-ring kit. Is this something I can just plug in? or will adjustments have to be made (I have ordered a 107 manual on cd, it just hasn't arrived yet) also, are there any special tools needed for the swap?

2. I have read all the horror stories about the catalytic converters being located under the hood in the 75' model.
realizing I cannot remove them, are there options as far as relocation? my first thought would be to purchase 2 new converters and have them relocated to the underside of the chassis with a new pipe to the exhaust manifolds. the other idea is similar (depending on if they are connected to the exhaust manifolds or not) can I swap out 74' exhaust manifolds for the 75's and then relocate the converters to the undercarriage?

thanks..

This is a D-jetronic system with electronic fuel injectors and a metal rail running a circle above them, right ?

I have a .zip file I send people with the various diagnostic procedures and system descriptions. You'll have to send me an email so I can send it to you.

to replace one injector usually means pulling the whole rail. Buy the TWO rubber bits for each injector. They're like 3$/injector. One piece is a rubber boot on the tip of the injector. The other is the ring on the injector.

There are no special tools required other than a C-clip remover (if you change the rubber rings on the other injectors). But to check out the system correctly, you should have a fuel pressure guage that reads in the 20-40psi range (correct system pressure is 32psi).

It doesn't hurt to replace all the fuel lines if they even look old. Also there is an incredibly critical hose from the manifold to the manifold vacuum sensor (mounted under the brake booster last I saw). Make sure it's brand new. A little vacuum leak goes a long way.

Of course, if your motor is CIS, then "never mind".

-CTH

The standard leak from D-jet injectors is from the swedged rubber hose at the top. This can easily be removed and the hose replaced. I would suggest doing them all as the act of removing one will usually cause others to start leaking. Get the proper hi pressure hose from a MB shop. Also get the proper 13mm hose clamps, not just any worm gear clamp. I'm in Aruba right now or I would give you part numbers.

The 1974 manifolds will work, or 77-80 ones. Use the catalyst intended for a 77on car.

Fuel injector hose replacement
 

Hi LoBo:

I just completed replacing all of my injector hoses.

It is not a bad job for a DIYer All the hose clamps and required materials come with the kit.

Nice not to see or smell any gas anymore not to mention the risk of fire.
Good Luck
Razorman

75 450 SL 108000 MILES