Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: FresnoBob on October 07, 2023, 18:46:35

Title: Cold start valve nozzles
Post by: FresnoBob on October 07, 2023, 18:46:35
During hot and cold starts my newly rebuilt 250 engine starts roughly and takes a few throttle jolts to "clear her throat" and then runs smoothly.  I suspect the CSV nozzles, which spray fuel in a tulip bulb shape and far from anything like atomization.  Are new nozzles available from anywhere?  What is the typical spray pattern for these nozzles?  Am I barking up the wrong tree?

Thanks,

Bob
Title: Re: Cold start valve nozzles
Post by: Lori on October 07, 2023, 20:51:36
This post should probably be in the Drive train, fuel, suspension, steering & brakes forum instead the Full member forum. 

I don't believe anyone sells the nozzles but if you search the above forum, there are some threads about cleaning them.  Ultrasonic cleaning seems to yield the best results.
Title: Re: Cold start valve nozzles
Post by: mauro12 on October 07, 2023, 21:59:46
I’ve recently replaced the cold start valve needle , this is what you mean I guess .
Mine was leaking and not sealing properly anymore . The only website I found was the sl shop uk. I hope this helps , is quite inexpensive but the item is smaller than you can imagine . I was surprised when I received the package .
https://parts.theslshop.com/mercedes-benz-sl-w113-pagoda-cold-start-needle-valve/

Title: Re: Cold start valve nozzles
Post by: ja17 on October 08, 2023, 04:19:35
Bob, you will need to determine if is starting rich or lean. Try a cold start with the intake solenoid dis-connected.
Title: Re: Cold start valve nozzles
Post by: mauro12 on October 09, 2023, 12:33:25
The csv does not atomize fuel but is more a weak spray
Title: Re: Cold start valve nozzles
Post by: FresnoBob on October 09, 2023, 22:01:11
Thanks for the information from everyone.  I have ultrasonically cleaned the CSV and the needle valve seems in perfect shape.  Perhaps I'm expecting too much from a 1966 spray nozzle.  I've tried starting the car with and without power to the CSV and it starts much better with the CSV when cold, but it starts better without the CSV connected when hot.  I suspect my one-second solenoid is set longer than necessary.  I've tried to adjust this very delicate device a few times and frankly don't know the proper configuration.  Any suggestions?