She's let me down again.... - PeachParts Mercedes-Benz Forum

zu! · #1 12-22-2016, 11:24 PM

Been performing like a champ the last few really cold days. No issues starting even after days of being parked in minus 10 degree nights.

Today was actually warmer. 3 degrees in the morning. Leaving to meet a client and she wouldn't start.

Glow light cycled as it should. I usually wait a few seconds after the light offs and then crank her and she usually starts without complaint.

Not this morning though. Cranked until the battery was weak and still nothing. Wasn't even close to catching. So I plugged it in (block heater).

Plugged it in all day and made sure it was good and hot. Still no go. Used booster battery still no go.

I had half tank in there so I know I have fuel. For good measure poured in 20 liters spare that I have. Cranked again. Still no go.

I'm wondering...could electronics cause this? I have fuel. I have heat. What else could cause this not to start?

Sorry W124 300TD. 1987.

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sixto · #2 12-22-2016, 11:56 PM

Are you sure the glow system is working? Pull the larger 6-pin connector at the glow relay and check continuity of each socket to ground. Anything less than 0.6 ohms or over 1.0 ohm indicates a bad glow plug or bad connection between the connector and the glow plug.

Your oil might not be rated for low temps but it doesn't sound from your description that the starter is struggling.

Sixto 1, babymog 0 in the 617 vs 603 ease of cold starting contest

Sixto
83 300SD

zu! · #3 12-22-2016, 11:59 PM

I checked that. All showed 0 ohms. But even if they did, remember my last GP saga? I started the car with no glowplugs at all simply by plugging the block heater in for a few hours. This time, I plugged it in for a good 6 hours. The engine was warm to the touch when I tried it again.

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zu! · #4 12-23-2016, 12:03 AM

Btw sixto, my old 617 never let me down even once. This one..has left me sad and disheartened so many times. I can't even call for a tow cos I've lost all my towing privileges with BCAA due to going over the max tows allowed. Yes. It's been that bad.

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sixto · #5 12-23-2016, 12:04 AM

Is the stop lever all the way up while glowing and cranking? To be sure, disconnect and cap the vacuum line to the shutoff actuator. Tie the stop lever as far up as it'll go while testing.

Sixto
83 300SD

zu! · #6 12-23-2016, 12:43 AM

Yes it is all the way up. I had someone crank it whilst I watched.

I'll say one thing though...those fancy electronics behind the battery were all wet. Would that cause anything?

What else could cause this non-starting event? And yes, I did run the gear lever back and forth...just in case.

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Diseasel300 · #7 12-23-2016, 11:53 AM

The electronics behind the battery shouldn't affect starting or running. The injection pump is mechanical in nature.

Just because you have fuel in the tank doesn't mean you have fuel being injected. If the block is warm and it's been starting fine, you likely have air in the lines or a fuel leak. Crack the injector lines and see if they're spurting fuel.

Barring anything else, try spraying some WD-40 (don't use starting fluid) in the intake and seeing if you get some attempts to fire. If you do, you know you aren't getting fuel delivered to the cylinders.

psaboic · #8 12-23-2016, 12:02 PM

Silly question probably, but are you sure your feul is not gelled in those temperatures....I would try starting it from an alternate fuel supply (bypassing the tank and spin on fuel filter) just to be sure.

psaboic · #9 12-23-2016, 12:02 PM

Silly question probably, but are you sure your fuel is not gelled in those temperatures....I would try starting it from an alternate fuel supply (bypassing the tank and spin on fuel filter) just to be sure.

Diesel911 · #10 12-23-2016, 12:54 PM

From what I have read you have verified you have Fuel in the Tank. It has not be verfied you are getting Fuel up to the Injectors.

Loosen several Fuel Injection Line Nuts at the Injectors and crank the Engine and see if you have fuel coming out.

The Fuel gelling is an interesting thought.

zu! · #11 12-23-2016, 06:26 PM

Guys, I just got back from meetings. Is it possible something is blocking fuel at the tank? Is there any merit to blowing it backwards with compressed air....say from the little plastic filter back?

Temps now are not that cold...I'd say 2 deg centigrade. I thought fuel would only gel at minus 20 or so?

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zu! · #12 12-23-2016, 06:41 PM

Ok just verified that I have fuel coming out of all the injectors by cracking them all. They were all wet. What now?

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zu! · #13 12-23-2016, 07:09 PM

Ok just checked gps again. All of them were 0.5 milli ohms and only 1 GP5 was 8 milli ohms. I didn't know but my daughter had a high end fluke as she's an electrician.

Still that doesn't solve the no-start cos I have started it with NO GPs before and just the block heater heating the engine till it was warm to the touch.

What the heck am I missing here?

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vstech · #14 12-23-2016, 07:28 PM

Fuel wet at the injectors... but was it squirting out?

zu! · #15 12-23-2016, 07:36 PM

Squirting? Hard to tell. I need someone to crank it whilst I look. But it was plenty wet when I looked at it.

Seriously...I'm beginning to think it's something electronic. I see a lot of "nuts" leaves and seeds in the engine compartment. Looks like mice might be living in it (and this is daily driven!!). Could there be some wires chewed that might cause the car to crank but not start?

FYI alarm was disabled long ago by pulling out the plugs. It was that way when I bought it.

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