[W126 Coupe] how do you adjust

[Gary]

forgot to mention  1991 560 sec 




________________________________
From: Gary <garysalas at yahoo.com>
To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
Sent: Mon, July 19, 2010 2:01:21 PM
Subject: Re: [W126 Coupe] how do you adjust


thanks...would happen to know those numbers?...i don't have the manuals.  




________________________________
From: Dick Spellman <dick.spellman at gmail.com>
To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>
Sent: Mon, July 19, 2010 11:59:35 AM
Subject: Re: [W126 Coupe] how do you adjust

Hi Gary,

Just check the pressures chart in the manual so the shop will be using the 
correct values for your model year.

Take care,

Dick


On Mon, Jul 19, 2010 at 1:47 PM, Gary <garysalas at yahoo.com> wrote:

it was running very rough, then stopped running.  would turn over.  i took it to 
the garage and the fuel pressured it and the FD was the problem.  i probably 
should just take it back to them and have them do the fine tuning since they 
have the tools.    i'll give them a copy of your info, can't hurt.    thanks 


>

>

>

>

________________________________
From: Dick Spellman <dick.spellman at gmail.com>

>To: Mercedes Coupes Mailing Lists <mbcoupes at mbcoupes.com>

>Sent: Mon, July 19, 2010 9:37:12 AM

>Subject: Re: [W126 Coupe] how do you adjust

>

>

>Gary,

>

>You need to put a fuel pressure gauge on the fuel distributor (fd).  At a 

>minimum you can connect to the cold start valve outlet (upper fd chamber) on the 

>fd to obtain overall pressure.  Ideally, you want a gauge that permits 

>connections to both upper and lower chambers (two hoses with a shut-off valve on 

>one)) so you can measure the difference between upper chamber and lower chamber 

>pressures (referred to as differential pressure) in the manual.  Typical fuel 

>pressures would be 5.3~5.4  bar overall.  When isolating lower chamber pressure 

>it should be approximately 0.4 to 0.45 bar LESS than the overall pressure.  This 

>would be your differential pressure which is in the manual.

>

>So, as an example upper chamber is 5.3 bar and lower is 4.9 bar, differential is 

>then 0.4 bar.  Without knowing the pressures it is difficult to recommend a set 

>of steps to remedy your problem.  Two quick questions:

>

>1. did you replace the rubber o-ring (seal) at the base of the fd when you 

>swapped out?  If not, a vacuum leak (large) will likely exist where the fd bolts 

>down on the air flow meter housing.

>2. what running conditions did you have prior to the swap?

>

>Good luck,

>

>Dick

>

>

>On Sun, Jul 18, 2010 at 10:57 PM, Gary <garysalas at yahoo.com> wrote:

>

>the fuel distributor.  i put one from a donor car and need to adjust because the 

>car just turns and turns   thanks for the help

>>The MB Coupes Website!

>>W126 SEC Mailing List

>>Postings remain property of MB Coupes, L.L.C.

>>

>

>The MB Coupes Website!

>W126 SEC Mailing List

>Postings remain property of MB Coupes, L.L.C.

>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.pairlist.net/pipermail/mbcoupes/attachments/20100719/35fcb9e1/attachment.html>