Author Topic: CSV Needle Valve Problem (Read 11739 times)

sjiatrou · « **on:** February 13, 2010, 04:56:30 »

I have been having cold start problems in my '64 230SL (#1515), takes about five or more tries at 15+ seconds each crank and eventually it catches. Once it starts there are no problems whatsoever. I can restart with no troubles within an hour after shutdown but then it's back to the original tough start condition. So tonight I dismantled the CSV and discovered that the needle valve was stuck against the Fuel Line Filter Screen. I freed that and cleaned everything out but upon reassembling discovered that when the Filter Screen fitting is fully installed the Needle Valve is wedged between the screen and the Valve seat! How can this be? I've reviewed the Tech Manual (http://www.sl113.org/wiki/Engine/ColdStartValve) and am sure I'm putting it back the way it is supposed to go. The Needle Valve is distorted at the non-flange end so I suspect that it has been hammered by the solenoid plunger and jammed against the base of the housing.
This may be a naive question but are there different sized needle valves? Did the previous owner jam an incorrect needle valve in here and screw up my CSV?
And one last question I hate to ask: when I removed the CSV I found there is no dual internal jet, just a single jet coming out of the housing, does that make sense?

Note: I've been driving this car for 2+ years and it has started fine up until a about a month ago.

Pictures attached
Thanks,
Steve

J. Huber · « **Reply #1 on:** February 13, 2010, 05:13:46 »

Hi Steve. I cannot help much but would think yours should have a two-port sprayer. (and is the spring in there?)Good luck. Maybe someone will have a spare needle off an otherwise out of commission CSV?

sjiatrou · « **Reply #2 on:** February 13, 2010, 05:18:48 »

James:
I was afraid of that. Yes, the spring was in there.

Thanks for the quick post.

Steve

ja17 · « **Reply #3 on:** February 13, 2010, 05:40:19 »

Hello,

If it started before, it should start now. Did you check the starting solenoid on the injection pump also?

sjiatrou · « **Reply #4 on:** February 13, 2010, 05:50:05 »

joe:
That's what I thought. I've checked the thermostat on the FIP (it seems to operating fine), I've changed the FIP air filter and changed the oil in the FIP with no changes that's when I decided to go after the CSV. I'm working my away around the system. I'm learning quite a bit along the way, just not getting the results I'd like.

Steve

hands_aus · « **Reply #5 on:** February 13, 2010, 05:54:57 »

relay contacts?

sjiatrou · « **Reply #6 on:** February 13, 2010, 06:23:07 »

I don't think so, I cleaned all the contacts and everything seems to click.

tel76 · « **Reply #7 on:** February 13, 2010, 10:56:29 »

Hello Steve,
I may be missing something here but the needle should not come into contact with the union/filter.
The filter goes into the housing first then the spring then the valve so when the solenoid is energised and the pin extends it pushes the valve which in turn acts on the return spring.
Have you checked the solenoid extending pin, is it coming out of the unit too far.
Your valve should not be distorted like it is and you require a replacement.

sjiatrou · « **Reply #8 on:** February 13, 2010, 17:39:50 »

Eric:
Here is an exploded view of the CSV as I found it. The filter is still in the housing on the right, the valve was wedged against the filter with the spring in between. I tested the solenoid and it activates with 12V applied and extends the plunger approximately 1/8". I'm confused about the physics of this CSV because when I reassembled the valve there is no play between the valve and the valve seat. With the filter housing fully installed the valve is pushed tightly against the valve seat. To have any play between the valve and the valve seat I have to back out the filter housing leaving it loose (I'm sure that's neither optimal nor desired!) It also seems that the 1/8" throw from the solenoid cannot reach past the valve seat to engage the valve even if there is some play. I think I understand how this is supposed to work, I'm just not seeing how it can possibly work the way my CSV is configured. Note: the needle valve in the picture is oriented in the direction I found it. Is the needle supposed to point toward the housing and enter the valve seat? Mine is so distorted it will not fit in into the seat opening.

Having searched the forums/tech manuals/vendor sites it appears that the 230SL CSV is nigh impossible to obtain, are there any alternatives or work-arounds to my situation?

Thanks!

Steve

abe280SL · « **Reply #9 on:** February 13, 2010, 18:03:44 »

I think your vaulve is 180 degrees off....you need to turn it around and the spring is connected to the little round side not the long ridged side. Look up pagoda sl techinical manual in the wiki and there are lots of pictures there.
abe

sjiatrou · « **Reply #10 on:** February 13, 2010, 18:12:46 »

I was afraid of that. Thanks. I had looked at the pictures in the Wiki which is what prompted me to start this thread: mine did not look the same and I could see no evidence that mine had ever been tampered with.

Back to the bench!

Thanks to everyone for their patience and help.

Steve

sjiatrou · « **Reply #11 on:** February 13, 2010, 19:24:41 »

As far as the cold start issue, it seems that the CSV was the problem. I filed down the needle (just the distorted fins not the face) so it could be installed with the correct orientation and reassembled and reinstalled the unit. The car fired right up and then proceeded to idle rich and rough. I removed the 7mm bolt on the side of the CSV and restarted, fuel jetted out for the first second (looking good so far) and then cut off (still good) but then trickled out steadily after that (not good).

Very frustrating on a 70 degree, cloudless Saturday in Monterey!

Now I'm in search of a new needle valve.

The fun never stops.

Steve

tel76 · « **Reply #12 on:** February 13, 2010, 22:35:00 »

Has anyone satisfactorily removed,cleaned and refitted the filter inside the union?

Naj ✝︎ · « **Reply #13 on:** February 14, 2010, 00:01:12 »

Hi, Steve,

I notice your car is a very early 230.
Does the CSV fit at the end of the manifold near the firewall or around the middle of the manifold just above the front suspension mounting holes?

naj

abe280SL · « **Reply #14 on:** February 14, 2010, 01:12:09 »

Quote from: tel76 on February 13, 2010, 22:35:00

Has anyone satisfactorily removed,cleaned and refitted the filter inside the union?

If you are talking about the metalic mesh...yes I have cleaned it. In olden days when the CSV would leak people got tired and their sollution to the problem was to use epoxy or something like that to plug the system. I had to take a needle and and fine screw driver like the ones you use on glasses to work out the epoxy and clean up the mesh (mess). That metal mesh is strong...so its hard to break.
abe

tel76 · « **Reply #15 on:** February 14, 2010, 10:13:27 »

Hello Abe,
How did you remove the retaining clip that holds the mesh in position, or did you clean the mesh in-situ?

abe280SL · « **Reply #16 on:** February 15, 2010, 06:29:23 »

I just cleaned everything in situ....I didn't know how to remove the clip. Soooo, if I can clean all the hard stuff without removing the mesh..you should be able to do the same. Maybe someone else can shed light if that clip is worth the risk of removing.
\abe

sjiatrou · « **Reply #17 on:** February 16, 2010, 21:56:24 »

Quote from: naj on February 14, 2010, 00:01:12

Hi, Steve,

I notice your car is a very early 230.
Does the CSV fit at the end of the manifold near the firewall or around the middle of the manifold just above the front suspension mounting holes?

naj

Naj:
It fits in the middle just above the suspension mounting hole.

Steve

Naj ✝︎ · « **Reply #18 on:** February 17, 2010, 19:26:13 »

Thanks, Steve.

In that case it should have twin spray nozzles as shown in the wiki.

naj

tel76 · « **Reply #19 on:** February 17, 2010, 22:24:44 »

As a matter of interest you can remove the twin spray nozzle for cleaning from its housing ,the problem is it is only an interference fit in its housing,if this interference is lost the nozzle goes through the engine.
Has anyone had this problem?

sjiatrou · « **Reply #20 on:** February 18, 2010, 02:37:53 »

I shudder to think of where the nozzle is now! Are there other MB models that have this same CSV in case I run across one in the junkyard.

I managed to get the needle valve/solenoid to work properly, nice quick jet of fuel when I turn the switch and then no leaks/drips after that. Will the lack of the dual nozzle cause any damage or cause performance problems?

Thanks again,
Steve

jacovdw · « **Reply #21 on:** February 18, 2010, 09:51:48 »

Steve,

The lack of a dual nozzle would not cause any damage as it is only used when starting the car.
Neither would it cause any performance issues whilst driving unless the needle valve is leaking (yours is not as you mentioned).

What are the numbers on the little Bosch ID tag on the CSV (can't see it clearly on your photo)?

I'll check the numbers on the twin jet CSV of my early 230SL (our cars were "born" about a month apart) and forward them to you.

sjiatrou · « **Reply #22 on:** February 18, 2010, 15:53:32 »

The tag reads: Bosch Germany Importe D'Allemagne EP/EV 2/2

Thanks!

Steve

jacovdw · « **Reply #23 on:** February 18, 2010, 16:07:15 »

Steve,

Mine reads EP/EV 2/3.

News:

Author Topic: CSV Needle Valve Problem (Read 11739 times)

sjiatrou

sjiatrou

sjiatrou

sjiatrou

sjiatrou

abe280SL

sjiatrou

sjiatrou

abe280SL

abe280SL

sjiatrou

sjiatrou

jacovdw

sjiatrou

jacovdw