Pagoda SL Group

W113 Pagoda SL Group => General Discussion => Topic started by: merrill on September 18, 2005, 16:46:53

Title: prime fuel system?
Post by: merrill on September 18, 2005, 16:46:53
recently I changed my fuel filter & did not replace the fuel in the filter housing.
Do I need to do anything to prime the fuel system?
should I just let the fuel pump run a little longer before cranking the motor?

Thanks in advance.
matt
Title: Re: prime fuel system?
Post by: Raymond on September 18, 2005, 20:36:51
You can purge the air by losening the connector on the top of the filter housing and then turning the key to get the pump running.  The air will hiss out quickly and when you start to get a flow of fuel out the threads, re-tighten the connector.  

Even if you do nothing, the air that gets into the system should not be a big problem.  The engine will probably crank longer before starting or run and stumble, miss or stall at first, but should be fine after it runs a bit.  



Ray
'68 280SL 4-spd Coupe
Title: Re: prime fuel system?
Post by: ja17 on September 18, 2005, 21:56:56
Hello Matt,
The engine will self prime. It may take little extra cranking. Remember the fuel continually circulates in a loop and goes back to the fuel tank. Just turn the ignition key and let the electric fuel pump run for about 30 seconds this will fill the fuel canister and purge the line. Push the accelerator to the floor while cranking for this start. Some air may  get to the injector lines but will soon be gone.

Joe Alexander
Blacklick, Ohio
Title: Re: prime fuel system?
Post by: Chad on September 18, 2005, 23:30:47
this may sound silly, but i routinely let the pump run for some time (20-30secs) prior to cold starts. somewhere i imagined reading its to generate good pressure in the pipes.  the car starts fine.  does this make sense?

-CD-
1967 230SL, 113.042 10
1983 300TDT, 123.193
Title: Re: prime fuel system?
Post by: rwmastel on September 25, 2005, 20:36:47
Chad,

That shouldn't be necessary.  Try 10 seconds on your next cold start, then 5 on the next one, and so on.  You will eventually find what's necessary for your particular car.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420
Title: Re: prime fuel system?
Post by: Chad on September 25, 2005, 21:14:06
Sounds good will do.

-CD-
1967 230SL, 113.042 10
1983 300TDT, 123.193