Ater changing the glow plugs and filters on a car that had sat for nine months the 1976 300D won't start. Likely I knocked a vacume or linkage off. What is likely?

Other observations. All the filters were very dirty. The loop glow plugs were intact, but harder than it seemed right to pull out after being unscrewed.

The clear small fuel filter has a air bubble in it after I installed it. That looks wrong.

As far as I can tell I reinstalled all the vacume lines, but I've only got the basic knowledge.

Thanks

Did you pump the primer?

Is something wrong to have air in that filter.

A single large bubble is normal.

Once you have primed the pump, it may take ~30 seconds of cranking to clear all the air out of the injection lines.

There seems to be some difference of opinions on what it necessary/ adviseable to open to help bleed the system. I didnt solve the problem yet

The manual primer pump is supposed to clear all the air out of the fuel system. I think the manual says pump it for a minute or so. But like Forced said, I don't think it can clear the air from the hard lines that run to each injector. Cranking the engine will do that.

You said it sat for 9 months. Did it start before you did this work? If not, then maybe you did everything right and something unrelated is wrong.

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'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

oooh, there was a thread on here a few weeks ago that talked about the difficulties of converting that system to the pencil plugs. THAT is what I would do. but it's unlikely that is what is causing the no start problems you are having.
I would open all the nuts on the hard lines going to each injector, and crank the motor over and over until fuel squirts clear without any bubbles escaping from the nuts.
did you fill the spin on filter with fuel before you put in on? it will take a LONG time to hand prime a dry spinon.
John

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Yes, I forgot to fill the bigger fuel filter. . . I didn't know that it would be so serious of a mistake.



Tommorrow I'm going to take the advice of cracking the hard lines at each injector, and keep cranking until I see clear fuel passing. (Thanks, any more hints)

only other thing I can think of is to loosen the spin on top bolt, and pump the handle until fuel squirts out of the top.
John

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Ahh.
We couldn't figure this thing out. I brought in a professional mechanic and also he brought someone with experience in auto electric, who also happens to own three mercedes diesels. Together we couldn't get it stated.

It is true I messed up by trying to start the engine without filling the fuel filter, but we thought that problem was fixed. We have made sure that the system is primed, fuel comes out of the top of the filter when it is cracked. And when cracking injector lines, the fuel is squirting.

Well tomorrow is another day, and the mechanic has a source for a real shop manual rather than my Chilton version. He will also calibrate the valves.

I am still looking for advice. Our conclusion is it should start, but it isn't.

Sounds like time to check out the glow plug circuit for it's funtion. I do not think the average engine will start usually from ambient temperature without them.

We've tried starting by bring positive directly to the first glow plug. (This is a 1976 300D, so the Glow plugs are in Series.) And the ground after the last glow plug is also working.

I agree that I must have messed up something, and since we have double checked that fuel is getting to the injectors, and that the glow plugs are on, I stretching to figure out what else I might have done wrong.

how are you verifying the glows are working? are you measureing voltage at the last plug? it should be reading around 3 volts to ground at the last plug.
you could also order some upgraded pencil style plugs from ******** az.
John

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Judge,

Heat the GP for a long time at night and observe the resistance wires between the GP. U should see a slight glow in the these wires if the GP are operating correctly.

Another way to check the GP is to take #1 out, hook it up properly and see if it glows.

P E H

I took it to a mercedes independent shop, they insisted on checking the compression before working other issues. With the injectors removed, I could see all 5 injector glowin orange. I saw the links between the 3-4th injectors getting too glowing hot. (I wondered if there could be a partial ground between the loop and a carbon buildup, but I am a DIY guessing)

There is a washer like gasket at the botttom of each injector. I read that it should always be replaced. Instead it was reused, could reusing that gasket drop the compression enough to matter?