True, try to start a 603/6 on a hot summer day without GP's, good luck. But this is a 617 were talking about, they are not exactly picky.


If the engine is in half way decent shape, and its above 70 it should light right off.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I'll try the glowing for 30 seconds and see if that helps.
Plugs are only 8 months old.

No WVO in the car in months and both filters changed after this started happening to see if that was the problem. Didn't change it at all.

The hard starts happened suddenly. One night I put her away for the night, the next day she was hard starting.

She's never been picky before but tonight I plugged in the block heater. Wonder what will happe in the AM.

Starter sounds peachy. Turns fast until the battery starts to lost it.

There was a small problem with the ignition for a while. The glow light wouldn't always come on. I'd have to turn the key several times until the light came on to start it. To my knowledge the car never was attempted to start unless the glow light was on. That prblem fixed itself and the light comes on every time.

If the plugs are less than a year old, could it be the relay?

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Ginny in Denver-ish
78 300SD, 265K (mine)

goto dieselgiant.com (i have no affiliation) there on the Mercedes diesel page they have a good troubleshooting guide for both the relay and glow plugs. go and give it a look and a try if you have a voltmeter, worst case you need a new relay and a new set of glow plugs.

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'81 300D - swapped to a 617.951 turbo motor with a 150 amp alt.

Sounds like low compression to me, and only will light off when the rings are lubricated. You may also want to try removing the shut off valve line while attempting to start.

__________________
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.

It's not low compression.

Car was plugged in all night and started right up.

Car doesn't and has never smoked or used oil. A small oil leak but small enough that I never need to add oil between changes. at 5000mi.

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Ginny in Denver-ish
78 300SD, 265K (mine)

It's glowplugs. You need to borrow or buy a multimeter to check the voltage the resistance on the plugs, although Barry's non-multimeter methods will provide some data. I think all the SD's had parallel plugs and not series plugs since they are turbo engines. If so, you can ignore what Barry had to say about the squiggly wires.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

From your description:
* Bad glow plugs are very possible, What brand was used?
* Bad glow plug relay is possible.

wont start for anything! 1985 300SD

Diagnostics post 65 - 171.

Post 155, 156, 157 for pictures.


Glow plugs link thread
http://www.peachparts.com/shopforum/diesel-discussion/137732-glow-plugs-link-thread.html#post1019018




Have a great day

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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