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Discussion Starter #1
Greetings!

To start off with, let me assure you that I have searched, but not found anything quite like my issue.

Recently acquired my 1985 300SD. Was running well. Started to feel like it was losing power, so I changed the fuel filters. Now it's hard to start and will not idle. Thought it might be the valves, so I adjusted them. All the exhaust valves were tight, but none of the intake.

It will start if I hold the peddle just right, and I can get it to go to idle the same way, but if I lift my foot, it's as if I shut the key off. If I hold the peddle so it idles, and then turn off the key, it shuts off like it normally would.

Seems to run smoothly, thought is still lacking in power. If I hold the peddle at idle, it is a bit rough.

Any ideas?

Thanks!
 

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2012 CL550 4MATIC Coupe
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Maybe when you changed the FF some sediment got into the lines and clogged the injectors? Maybe remove and clean them out and check for volume and spray pattern.
 

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disconnect the vacuum shut off valve @ the IP, see if that does anything for you..

Jonathan
 

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Discussion Starter #4
Ok, I removed and plugged all 3 vac lines from the IP, one at a time, and it made no difference.

Have not had time to pull any injectors yet. Also don't have an injector test rig yet.

Thanks for the suggestions though.

Could it be something to do with the rack damper? It actually managed to idle at one point yesterday...then wouldn't again.
 

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Discussion Starter #5
1985 300SD will not start!

:mad::mad:

Over the last few months, I have tried repeatedly to start my car. I has so far always failed to start.

It was running poorly and not idling, so I did a home made diesel purge (mix of 50% Diesel Kleen and 50% Marvel Mystery Oil) I had it running on that mix for about 5 minutes. When it died, is the last time it has run.

Since then, I have changed all the glow plugs, and the fuse on the relay. I installed a manual override for the GPs because the light never comes on anymore. I connected a push button so that it causes the factory relay to pull in. I'm getting voltage at all the plugs, they all Ohm out ok, they are all Bosch.

I removed the purge setup, and reconnected to the tank. Still no go. This morning since it was 70 degrees F out, I decided to try again. I emptied the purge bottle and refilled it with fresh 100% diesel. Primed it with the hand primer. Primes fine. Try to start it an nothing. I don't even get any smoke from the tailpipe, though I can smell a burnt fuel smell...

I have also cracked several injector lines to make sure they are bleed and all seem to be. The hand primer moves way more fuel then the actual lifter pump though. I attached a video...hopefully you can view it. If not, I will have to convert it later. It shows the amount that returns when cranking, and then it shows how much returns when using the hand primer...please ignor the audio...don't know what happened there.

Where else can I look? It can't be the tank strainer, since I'm not pulling from the tank. Guess it could still be the injectors...I haven't pulled any of them yet.

Thanks!

Video is here: 0320111125.3g2 - File Shared from Box.net - Free Online File Storage
 

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Discussion Starter #6
Finally had time to pull the injectors and found all of the nozzles stuck closed from when I improperly tried running WVO blend fuel. Soaked them and got 4 of the 5 to free up. also found out I have 3 135 bar injectors and 2 115 bar, so I got a pair of used 135 bar, and swapped a good nozzle from a 115 onto one of my 135's...now I just need new heat shields so I can put it back together. Also flushed the injector pump with gasoline to clean any wvo out of it.
 

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can't run cold veggie or let veggie set up..stuff is MEAN!!

get yourself some Diesel Purge, dieselgiant.com has a good write up.

Jono
 

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Discussion Starter #8
Still no love

Alright, after replacing all the injectors with new heat shields, it still will not start.

There has not been any wvo in the system since I did the home brew diesel purge. Only fresh store bought petro diesel since then.

Still cranks just fine, but will not even try to start. Compression is low but still within specs. I even checked to make sure the camshaft is turning, thought maybe the chain happened to break at the same time, but the cam turns, and fuel comes out of the injector pump if I leave the hard lines off.

Could this really be just air in the lines? Is there a bleed port somewhere that I need to open?

Thanks!
Brian
 

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are you getting any fuel @ the injectors?

crack the lines, floor it and crank.
 
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