View Single Post
  #8  
Old 05-18-2011, 11:03 PM
daidnik daidnik is offline
Registered User
 
Join Date: Jan 2007
Location: Santa Barbara, CA
Posts: 179
I ordered from MB dealer

It would be wise to check your VIN in the MB database as there are a few variations with the needle seat/shutoff valve and there was a crossover point in the early engines.

I assume that you have an automatic trans. The crossover point appears to be a pretty early engine number:

115.920-12-006995

The last series of numbers ID's the S/N. The 115.920 ID's the engine type, 4-cyl 220 & the -12- is the auto trans.

Anyway, my recollection is that stock was Germany, which takes about 1 week to get. Aside from that crossover point, those two P/N's should be the ticket as the crossover is the same for the gasket & the o-ring.

On the shutoff valve, what has probably happened is that the wire is broken. This tends to happen pretty close to the solenoid as it sits above the exhaust manifold.

Given that you have this, I would definitely recommend taking the carb off which is pretty easy. It will also give you a chance to see if you've got a leaky rubber mounting flange. This is the part that the carb bolts directly to and acts to dampen shock/vibration to the carb.

If you need a new rubber mount flange, which is very easy to replace after the carb is off, I can say that Febi makes a replacement that can be had for ~$20. These flanges do tend to develop cracks/vacuum leaks over decades of service.

The most important part in taking the carb off is to mark ALL the hoses. There are ten hoses (I think) all mounted on a carb about the size of your two hands clasped together. Just use masking or blue painters tape & label IN, OUT, FRNT, BCK, MID, etc to keep them straight.

The four special bolts to the rubber mount flange then gets the carb off. Once you've got that thing off, you can do your o-ring more safely. You don't want to cross-thread the shutoff valve which has a very fine thread into the pot-metal casting. You'll also be able to clean the carb & the float chamber.

You can troubleshoot the shutoff valve as a a unit by applying +12V to the wire and ground to the metal part of the shutoff valve. Gently wiggle around the wire in the vicinity of where it pokes into the solenoid an I think you'll find the open/broken circuit. Hopefully you've got enough wire to do a solder joint & heat-shrink tubing surgery on. Once you've fixed one of these, you know to treat them very gently. Always disconnect the push-pin connector before tweaking the mixture or you risk breaking the aged wire.
Reply With Quote