Cold start - car sitting for a week

[glcg123]

My 65 230SL normally starts well when cold. However as this is a pleasure car that never sees rain it may sit for a week without starting. In this situation the car takes a fair bit of cranking to get started. I cleaned the CSV as best I could, could not find the inlet screen, and it is getting power to the solenoid. In a poor start situtaion, sitting for a week, if I crack the inlet line to the CSV there is no fuel in it. When I turn on the ignition fuel does come out. Once the fuel flows it starts right away. It seems to me that there is air in the line and it does not get displaced quickly enough by the fuel. Cracking the line allows the air out and fills the CSV feed line with fuel.

If I leave the car for a day again it starts right away. When I crack the inlet line with the ignition off fuel does come out.

Is there a check valve that keeps fuel in the line that feeds the filter? The CSV line is right behind the filter it and it would make sense to me to keep the fuel in there. We had a diesel truck that had a poor cold start and one of the check valves in the fuel system was malfunctioning. Is this condition nromal, poor start when sitting for a week?

George 1965 230SL - 4 spd

[A Dalton]

G.
 There are residual checks at the electric pump outlet and the Injection pump  has a pressure check at the return line, but they will not usually hold for weeks.
 The best start procedure in this case  [ and anytime, really ] is to turn the key to Run position for 15 seconds  and then start the car..this allows refueling of the lines and system before Ignition.

 You may also have a leaking CSV.. this can be checked by turning the key to run position [ energizing the elect pump] and taking the small hex/test plug  off the side of the CSV .. there should be no fuel running out the port with pump running.. it should only have pressure
at this test port when starter/csv are energized.......
 You say yours holds pressure until a following day  , so I doubt you will find any leaking by there....

[ja17]

Hello George,

Make sure your fuel filter is clean. If it is restricted your fuel system will take longer to pressurize during start ups.

In more severe cases, a dirty screen in the gas tank or electric fuel pump inlet can also slow the fuel supply.

The advice on running the ignition for a few seconds before starting is helpful.

Doing a fuel pressure and volume check and/or examining the condition of the fuel tank by removing the fuel guage sending unit will indicate the condition and cleanliness of the fuel system.

Joe Alexander
Blacklick, Ohio

[Abbas]

George
 Make sure that your battery is strong. Recently I changed my battery from 45 amps to 60 amps and the car when coldw started faster.

Abbas

280SL W113 1969 Ivory
E280 W124 1995 Silver

[glcg123]

I have a new, high output battery and the fuel tank was cleaned and relined. The fuel lines were also blown out. I usually leave the key on for a few seconds. What do your cars start like after sitting for a week?

George

[France]

George,

Hate to tell you, but I routinely leave Carling unmoved for up to 4 months.  Every time I start (not just when I return, but every time I start the car) I leave the fuel pump running for about 15 seconds, as suggested by A Dalton.  Carling has never refused to start up on the first try.  This has been going on for 4 years.  

Now must I anticipate the posts warning me of imminent disaster?  Well, I can't help the fact that Sarasota is humid and hot for 5 months of the year...

Trice
1968 280SL US, signal red/bl leather, auto, kinder
Sarasota FL; Alsace France
There's two theories to arguin' with a woman.  Neither one works.

[glcg123]

For the past few weeks I took the advice of leaving the ignition on for a full 15 seconds when the car had been sitting for a week or in any cold start scenario. It fires up first try every time. I guess that what I thought was a reaso+nable length of time to allow the fuel pump to charge the system was in fact only a few seconds. I now look at my watch and make sure of the time.

Thanks for the advice.

George
1965 230SL - 4 spd

[ja17]

Hello George,

Make sure that the enrichment solenoid on the injection pump is working also. It moves the injection pump rack to full rich when the starter is engaged. You can run a 12 volt test lamp to the inside wire on the solenoid. The light should activate when the starter is in use. Check it's relay if it is not getting power. Sometimes the relay's contacts get tarnished from sitting. Next find out if the solenoid is good, run a hot wire to it (engine off) and you should hear it activate.

Joe Alexander
Blacklick, Ohio