No Gas through the injectors

[dwilli3038]

First let me explain I bought a car that needed work (may have been a foolish move) and the challange of making it work was one of the reasons to purchase.

I have installed a new fuel tank, new fuel lines from the gas tank and new injectors. I find the car will almost run on the gas from the cold start valve but will not fire at all when it shuts off. No fule passes through the injectors. When the fuel lines are lossen from the injectors there is fuel to each put does not appear to be much pressure, except cylinder #1 no fuel passes. If I remove the line form the injector pump for #1 cylinder the gass barely comes out of the injector pump.

I removed the line form the cold start valve and the pressure exceeded the 10PSI of my gauge range. I measured 1 liter a minute at this point but suspect the pump also was flowing some fuel through the return damper.

What is my next step? Anything else to check? Is it time to have the injector pump rebuilt? If so any recommendations?

Daryl
'64 230 SL
Serial # 508

[George Davis]

Daryl,

it takes quite a few revolutions of the engine to fill the fuel injector lines.  This is what I did when I had the lines off.  Connect a jumper wire from the cold start valve to battery positive, this holds the CSV open.  Then crank the engine until it fires on the fuel from the CSV.  It will keep running as long as you don't touch the gas pedal(! too much air kills it instantly).  At any rate, it only took a few seconds like that to fill the injector lines, I could tell when the engine started running poorly from too much fuel.  Jump out at that point and pull the jumper wire off the battery positive, and hopefully it will keep running.  Good luck with it!

George Davis
'69 280 SL Euro manual

[dwilli3038]

Hello Geoarge,
Thanks for the feedback, unfortunatly, that does not work for my car. I have gotten gas through 5 of the lines, but not enough pressure to open the new injectors.

Daryl
'64 230 SL
Serial # 508

[ja17]

Hello Daryl,

I agree with George. It sounds like you need more cranking time. All six plungers in the injection pump will not fail at the same time. Check the rack on the injection pump to make sure it is free. You can do this without removing the pump. You will notice much pressure from a loose fuel line. Keep us up to date Daryl!



Joe Alexander
Blacklick, Ohio

[dwilli3038]

OK so its sounds like I need to be a little more patient (it is not the first time that patience is an issue with me).

Specificaly how do I tell if the rack is free?

After I recharge the battery and start cranking with the cold start valve jumpered open, should I step on the gas petal?

Thanks for the advise

Daryl
'64 230 SL
Serial # 508

[ja17]

Hello Daryl,

Press the accelerator all the way to the floor for this first start. You are trying to fill the fuel injector lines as fast as possible. Make sure you are getting good spark and timing set close.

View the operation of the rack by removing the 10mm bolt and cylindrical cover. The end of the rack is threaded and you can insert the correct size screw and push and pull it. Or view it working by moving the linkage. See photo.

Download Attachment: rack cover.JPG
58.17 KB

Thanks,

Joe

Joe Alexander
Blacklick, Ohio

[J. Huber]

Out of curiosity, I just located the nut/cylinder cover on my pump. What are the yellow paint marks for? also on the injectors...

James
63 230SL

[George Davis]

Daryl,

Joe's method of holding the pedal down relies on the starter motor to crank the engine enough to fill the injector lines; holding the pedal down fills the lines faster.  After the lines are filled, the engine should start, but with this method you don't want to jumper the CSV open.

If you jumper the CSV open, don't step on the gas.  This method relies on the engine starting and continuing to run on just the CSV, rather than cranking for a long time.  My engine idled on just the CSV, but the throttle has to be closed or there will be too much air and it won't run.  Took about 5 seconds this way to fill the lines, then the engine started running badly, at which point I pulled the jumper off and it ran as normal.

George Davis
'69 280 SL Euro manual

[A Dalton]

On that pump, the rack is already in the full foward/rich position at starter crank via the rack solinoid......so CSV jumper technique works fine.
  For those interested , this test bolt JA mentions that screws into the rack on the earlier pumps [ pre R22] is 4mm x 0.8 , approx 40mm long . This is a great tool to have in your box and you can get one at any decent hardware store for a quarter.
 

[dwilli3038]

Thanks for all your comments and advise. I am headed to Bisbee, AZ to spend the holiday weekend with my daughter, but when I eturn I will try this out and let you all know the results.

Daryl
'64 230 SL
Serial # 508

[ja17]

Hello James,

The paint marks on your injectors and such are inspection marks placedf when the car was assembled new. They probably signified a check had been made for tightness.

Joe Alexander
Blacklick, Ohio

[J. Huber]

Thanks Joe. That was my guess. And Daryl, have fun in AZ. (take the clubs and the sunscreen!)

James
63 230SL

[psmith]

Hi Daryl,

Another idea, the 230 has it's own oil supply and filter.  Have you checked/cleaned/changed them lately?

Pete S.

[dwilli3038]

Hello Pete,

I did change the injector pump oil recently

Daryl
'64 230 SL
Serial # 508

[dwilli3038]

I removed the cap as suggested by Joe and inserted a small bolt. The rack seems free. When I moved the throttle linckage thrack moved a little, but it was easy to push it back. Is this normal?

Daryl
'64 230 SL
Serial # 508

[dwilli3038]

I jumped the cold start valve and cranked it until the battery died. It seemed to almost start this way. I charged the battery and this time removed the linkage so I could depress the petal to open the gas but leave the air closed. Same results. While charging the battery this time I removed the injectors one at a time and then connected them to the tube snf put a paper towel under them. I cranked for 60 seconds for each injector. There was not even a little dampness on the towel. After recharging the battery again I once again cranked with the cold start valve jumped. Almost starts but as soon as I remove the jumper nothing.

Daryl
'64 230 SL
Serial # 508

[graphic66]

Be careful or you will be needing a new starter. Starter motors are not continuous duty and if you crank to long things will melt. 15 seconds with a 30 second cool down may be OK. Just take a break and let things cool down.

[ja17]

Hello Daryl,

Try unhooking one injector line at the injection pump to see if fuel emerges from the4 pump during cranking!


Joe Alexander
Blacklick, Ohio

[dwilli3038]

I removed the line from the back of the injector pump (for #1 Cylinder) The gas barely dribbled out when I cranked. I removed the line from the front of the injector pump (for #6 cylinder)and the gas came out in a steady stream when the switch was on, and then did provide pulses when cranking but it seemed to me the pulses were not very high pressure I could nearly stop the flow with my thumb.

Daryl
'64 230 SL
Serial # 508

[ja17]

Hello Daryl,

Fuel should not flow out the injection line fittings of the fuel injection pump when the ignition is on. Remove the lines from the injection pump and make sure all the fittings are at 18 ft/lbs torque. Re-check for fuel leakage with the ignition on again. If you are still getting leakage, remove the fittings and see if the spring is missing. Keep us up to date.

Joe Alexander
Blacklick, Ohio

[dwilli3038]

I assume you mean the fittings on top of the injector pump that the fule lines connect to.

Daryl
'64 230 SL
Serial # 508

[dwilli3038]

I removed the 6 fuel line and turned on the switch. I had gas coming from the front 3 fittings. They were extemly tight. The back 3 were quite loose. I checked all 6 and they had springs. I torques them all at 18 ft lbs and then turned the key on. This time gad came from the fitting closest to the rear. I lostened the fitting and retorques it. Same thin gas game from the fuel pump pressure. I cranked the engine and found little gas from the front 5 nozzles and the 6th one spurted gas but the sourt was onl slightly higher than the flow from the fuel pump.

Daryl
'64 230 SL
Serial # 508

[perry113]

Yes it is time to pull the injection pump and have it rebuilt.
No exceptions to your fuel problem.
It's not that hard to do. Follow the manual which shows you to top dead center the motor prior to removal.
I did mine last year and sent it to Jerry Fairchild 530-241-1592
Send your pump thermostat along with the cold start valve and injectors. He will bench test everything so your smoth sailing once installed. I was refered to Fairchild by someone who had a 300SL pump done by him with excellent results.
He charged me $550 with shipping. Very fair. It could be more if yours requires more parts than mine did.


The old German guy in Long Island is much more expensive these days, but also does a good job. He did the pump on my 72 911 MFI 3 years ago back when his prices were around $550

[dwilli3038]

Where is Jerry Fairchild located? Is he part of a company or does he do this on his own?

Daryl
'64 230 SL
Serial # 508

[rwmastel]

quote:Originally posted by perry113

Jerry Fairchild 530-241-1592

Daryl,
You could always ask Jerry where he is.

I did find him mentioned on page 2 of this discussion thread:
http://index.php?topic=2491,fuel

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420