[W126 Coupe] no fuel flow

[Dick Spellman]

Hi Markus,

Flow.  You have a fuel regulator on the supply line before connecting to 
the fuel distributor.  That's where I'd test for fuel flow.  Also the 
return line and damper can be checked which if blocked would restrict 
flow on the supply too. Disconnecting at the fuel regulator will tell 
you if you have fuel.

Markus you need a set of gauges for most the pressure tests.  Read 
07.3-120 and follow the steps.  Given that the engine may have had 
excess fuel dumped in there I be sure check the pressures & cold start 
valve plus temp switch that drives this valve and hope the engine is not 
toast from raw fuel mixing with the oil.

Dick
not a mech, just a diy'r remember

Markus Meyer wrote:

> I have an 89 560SEL I just finished transplanting an engine and trans 

> into.  I know the motor is good, it came from a good working car.  As 

> a quick test, I wanted to verify I had fuel coming out of the fuel 

> line going into the fuel distributor.  That line is what I stuck into 

> a bottle to do the test.  Then, I jumpered pins 7&8 on the fuel pump 

> relay, and no fuel.

>  

> I tested voltage at each of the pumps (there are 2) and each read 

> about 10.5 volts.  I also tested continuity on each pump, both read 

> about 2 ohms.  I can hear both pumps "buzzing/humming".  I know 

> there's gas in the tank for two reasons - I added about 2-3 gallons, 

> and just to make sure it made it to the first pump, I pulled the hose 

> from the tank to the pump off and fuel poured out.  Also, when I got 

> the car, I was told the engine might be bad because "too much fuel" 

> was dumping into the engine, so I know there was flow at one point!

>   ;

> There doesn't seem to be an easy way to remove the "out" on each pump 

> one by one to test flow, considering the out on each pump is where the 

> wiring connections are, and I don't want fuel to pour onto the live wires!

>  

> So what can I check/test?  What could be the problem?  I should be 

> getting fuel flow by doing this test, right?  What the heck am I missing?

>

>

> Markus Meyer

> mfm at meyerprobateproperties.com <mailto:mfm at meyerprobateproperties.com>

> www.meyerprobateproperties.com <http://www.meyerprobateproperties.com/>

> Meyer Probate & Properties, LLC

> 484-919-9762

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