Author Topic: Starts on CSV then dies  (Read 6048 times)

paults1

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Starts on CSV then dies
« on: April 28, 2008, 19:54:23 »
Two weeks ago I started my '63 230SL after about 5 weeks & let it idle to warm up, then I ran it up to about 1500 RPM for a few minutes.  Later it would not start after the CSV shut off. After several tries I applied more throttle right at start up while the CSV was activated. WOW, it ran up & down the RPM ranges & not on all cylinders. I thought maybe the sparkplugs had fouled since low RPM runs rich. I replaced them with a hotter plug. Checked the timing, checked coil & all plug wires for spark, removed & checked the F/I lines with compressed air. The injectors are the R2 type & new about 5 years ago. I have not had a spray test done on these yet. I removed the top fittings on the F/I pump, cranked the engine & fuel shot out of all the F/I pump cylinders (this procedure is dangerous).  I did a compression test on the engine; #1@145,#(s)2,3,4,5,6 @150. Replaced all the above componets & started the engine. Again only started up with Cold Start Valve & immediately died. I posted this problem as a reply on the "Drive Train etc" Forum & thought I would get more response on this General Discussion Forum. I appreciate any advice or instruction on what to do next!!!

Paul, '63 230SL

Shvegel

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Re: Starts on CSV then dies
« Reply #1 on: April 29, 2008, 04:06:36 »
Any chance your ballast resistor for your ignition coil had expired? What you might be experiencing is that you have ignition while the car is cranking but it dies when you let off the key. This is becuse there is a wire that bypasses the ballast resistor and delivers 12 volts to the coil from the starter during cranking.

Check for voltage at the positive terminal of the ignition coil with the key on(not cranking).

dseretakis

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Re: Starts on CSV then dies
« Reply #2 on: April 29, 2008, 07:57:41 »
Sounds like you are going through what I'm going through with my 71 280SL.  If you haven't already, you might want to check out my long thread entitled "non-running 280SL".  I'm on the verge of giving up.  One last thing I'm going to do is change my plugs to non-resistor type.  If that doesn't work, then to a mechanic it goes.
Dimitri
71 280SL

merrill

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Re: Starts on CSV then dies
« Reply #3 on: April 29, 2008, 10:46:13 »
Paul,
have you checked the fuel pressure?  It is easy to check it at the csv connection.

will the car continue to run if you keep the throttle open a little?

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230
Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230

waqas

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Re: Starts on CSV then dies
« Reply #4 on: April 29, 2008, 14:46:33 »
While the car is warming up (<30mins), the rack in the fuel injection pump is moved to the full rich position by a solenoid attached at the back of the pump, and additional air is let in through a valve that sits directly on top of the injection pump. This is the high idle condition.

Once the car is warm, the solenoid moves the rack back to the normal operating position, and the air valve should close back up. If this is when your cars starts to stumble, then it may be running too lean. This might be caused by the mixture setting (less likely) or if the air valve above the fuel injection pump is stuck open after the rack moves back to normal (more likely).  You can check this by listening near the tiny air filter canister above and to the rear of the injection pump. If the 'hissing' continues, then it's still sucking air through this. You can adjust the position of the valve by adding or removing shims underneath the valve.

Joe Alexander (ja17) has a great description of this if you search the forums.

Also, Matt has a good point, check your fuel pressure first.


Waqas in Austin, Texas
Waqas (Wa-kaas) in Austin, Texas

paults1

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Re: Starts on CSV then dies
« Reply #5 on: April 30, 2008, 08:08:33 »
I checked the ballaster & it is at 12v.  Iam not able to run the engine to get get it warm to check the warm up device. Is there another way to check it?  When I give it more throttle at start up, it runs only on about 2 or 3 cylinders. I need more info on checking fuel pressure at the CSV & what should be the pressure?
Paul, '63 230SL
« Last Edit: April 30, 2008, 09:53:59 by paults1 »

waqas

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Re: Starts on CSV then dies
« Reply #6 on: May 01, 2008, 23:21:44 »
Another thing you could try is once you get it started (on however many cylinders) disconnect the linkage between the air flap and the fuel injection pump. Then try to move one and not the other to make sure the problem is not startup-mixture related. If so, the slight movement of one side (fuel OR air) should cause it to run better.

You may know this already, but I'll mention it anyway: A good place to disconnect the linkage is from the upper ball-joint of the vertical rod that connects the cross-linkage to the injection pump. DO NOT disconnect the lower end of this rod from the injection pump! (if you do, you WILL need to remove the entire pump from the car in order to have it reconnected correctly).

Waqas in Austin, Texas
Waqas (Wa-kaas) in Austin, Texas

waqas

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Re: Starts on CSV then dies
« Reply #7 on: May 01, 2008, 23:41:03 »
[collapsed into one reply]

Here's a great description by the legendary Joe Alexander:

"Engine Starting Aid Tour" http://sl113.org/forums/index.php?topic=5486

Regarding fuel pressure, here's the relevant data (thanks to ja17) :

http://www.sl113.org/forums/uploaded/ja17/20062593139_pressure%20check.JPG

This is taken from the following thread :-

http://sl113.org/forums/index.php?topic=4728

Hope all this helps!

quote:
Originally posted by paults1

I checked the ballaster & it is at 12v.  Iam not able to run the engine to get get it warm to check the warm up device. Is there another way to check it?  When I give it more throttle at start up, it runs only on about 2 or 3 cylinders. I need more info on checking fuel pressure at the CSV & what should be the pressure?
Paul, '63 230SL



Waqas in Austin, Texas
Waqas (Wa-kaas) in Austin, Texas