SOS: Help after fuel delivery work
 

ARRGH! Over the past 2 weeks I have been busy on my 86 300SDL. I replaced the delivery valve O-rings and crush washers, the little oil O-ring on the side of the IP for the manual STOP lever and the cruise control unit (thanks JamesDean).

In order to get to everything I also removed the intake manifold (replaced the gasket). I also pulled all of the glow plugs and tested them. Also reamed the holes.

I finally got everything back together Sunday, and after a lot of cranking (with rests in between) got the engine running. Let it idle for about 15 minutes, revved it up a few times, shut it off and then started it again.

All of my "car time" Monday was consumed with getting the under dash pieces back in. Today I started with the driver seat. Everything back together, so I wanted to do a test drive.

Engine would not start. Just cracked and cranked. Ran battery down enough that I needed a jumper again, so I moved other car close, added jumper cables and resumed trying to start the MB.

After a while all I get is a loud click. No crank. Left the jumper cables on for a while with some revving of the other car. Still nothing but click.

So, a few questions:

• Battery on MB shows 13.71V, battery on other car shows 14.8V. Is my battery gone?
• Is my starter gone? I sure hope not.
• Why would the car run on Sunday and not start on Tuesday? Didn't even try to start.
• Whoever thought that it would be a good idea to use the starter to prime the fuel delivery system was not quite right in the head.

It could just be a too hot starter and discharged battery.

I would let the starter cool off as in a few hours and put the battery on an actual charger, trickle automatic overnight deal would be best.

I always prime with the hand operated primer pump, I would also crank with a couple of injector lines loose at the head and tighten them once you see fuel, then move on to two others, it should start once you have fuel at a few injectors.

dont run it constantly and let it rest in between tries (I have also used a helper fuel at the intake, like wd40 or starting fluid but these are last last resorts)


It could have lost prime or just run off what was in the fuel filter, try refilling it with fuel and priming. you could also try jumping the starter solenoid, it is easy. or tapping on the starter while trying to start it, also easy. google will help with both.


Good luck, I am sure you will figure it out

That was the point of my last "question"; the 603 doesn't have a hand operated primer pump
Yes, I forgot to mention that when I first started it I had all of the injector lines off at the head. As each one got wet, I tightened that line up and continued. Once I got them all tightened it started pretty easily.

It is now acting like no fuel delivery; I guess I will have to try that again...if my starter and/or battery are not killed.

Update
 

Tried after 90 minutes of waiting and still just a loud click. :(

Try giving the stater a quick rap with a 2X4 or other good sized piece of wood. What may have happened is the starter gear may be jammed into the flywheel ring, and a good shock can sometimes free it up. Good luck!!

Update: not quite so sad
 

So after a few more days I decided to just try to crank the SDL again. Voila! It cranks!

But still no start. So I loosened all fuel lines at the injectors. Cranked for a bit and then went to look. All are wet. Tightened fuel lines back down.

So now I'm in better shape, but still not good. Here's the things I did in order:

1. Sunday afternoon: Final under hood reassembly. Cranked and cranked and got engine running. Stopped and restarted the engine a couple of times. Considered it a good day and stopped work on the car.
2. Monday: Fought with cruise control amplifier and the other relay-looking box on the same bracket. Finally got that bracket reattached. Installed kick plates under dash on driver's side. Did not attempt to start car.
3. Tuesday: Installed driver's seat. Tried to strart car. Cranked and cranked to no avail. Got sad and came inside and started this thread.
4. Friday: Tried to crank just for fun and starter is unstuck! But no start.

So I'm trying to figure-out what changed from Sunday to Tuesday to prevent the engine from starting. I installed and attached the cruise control amplifier and that other black box relay that shares the same bracket. Just for fun today I also disconnected the cruise control actuator (under the hood) and tried cranking. No Joy.

Any ideas? Is there any way to stop the engine from starting by connecting things up under the dash? I was able to observe the STOP lever and it is moving correctly.

PS: At this time of year in Houston, the need for glow plugs is completely optional.

Still sounds like you have lost the prime. Something leaking, not tight enough.

Charge up the battery?

Update
 

OK, so yesterday I cracked all of the fuel lines at the injectors (again). Cranked for about 15 seconds and had 6 wet injectors. Reattached the fuel lines and really cranked them down. Cranked down on the other ends also. Connected jumper cables to help with battery run-down. Cranked and cranked with no hint of starting.

So I've confirmed 3 times that I have fuel being pumped to the top of the injectors. Still no starting. Anyone have any ideas?

Check the glow plugs. Also it sounds like your starter may be near the end of its life...

As I mentioned earlier in this thread:

and I checked the glow plugs while doing all of this work. They were fine.

Also, the starter did lock-up once, but has had no trouble since. It is spinning the engine as quickly as ever.

I just don't understand why the engine ran well on Sunday and the following Tuesday it won't run at all.

Look, I live in Tucson and still use the glow plugs. IDI engines need the glowplugs, end of story. There's too much surface area in the combustion space that soaks up heat from compression. If it were direct injection, no glow plugs would be needed. Test your glow system next and report back.

As I said after my admittedly glib statement about not needing glow plugs:Are you suggesting that I check them again? I guess I could do that.

Apology and continuing saga
 

So first my apologies to mannys9130 and the forum. I had checked the glow plugs before reassembly and all was OK. The lesson is to check again :(

When I took mannys9130's advice and looked at the glow plug circuit, I noticed that the glow plug fuse was fried! I replaced the fuse, tried to start and fried the new one instantly.

So now I have pulled the intake manifold back off and I am looking for shorts. In the meantime, I have a question about the glow plug fuse. When removing the old dead fuse I accidentally touched the screwdriver across the forward glow plug fuse screw and a nearby ground strap. BIG spark. Is this supposed to happen (picture to show the exact points)?

Make sure the leads that attach to the glow plugs are oriented downwards. If pointed upwards even a small amount the will be in contact with the underside of the manifold and short.

Try a boat primer put in series with the supply line to the prefilter and use that as your primer sure saves cranking.