Hard Starting 240
 

Hey everyone,

As you may or may not know I am a new owner of a '78 240D 4spd. It has 128K miles on it. The PO had recently changed the glow plugs before I purchased it and done a fuel system cleaning(still the original style AFAIK, and not sure how severe the cleaning was), but it has some difficulty starting when cold. I haven't licensed it yet so it's been sitting. The glowplug light does come on for a full cycle, but it still starts hard.

I am new to diesels (especially 30yr old ones) and am not sure what to expect.

Thanks to all!

Try leaving the glowplug on a timed 45 seconds.... forget the suggestion light... and report back...

You have a series glowplug system on that engine if it is still OE. You can tell if it is working by looking at the heavy squiggly wires that join the plugs. Particularly at night, these will glow red. If they don't, your glowplugs are not working. On that system, if one glowplug goes out, none of them work.

If your glowplugs are not working I would recommend a change to the retrofit pencil plugs

Are the valves adjusted properly?

Scott

Thank you guys for the quick replies,as usual. This forum has been THE BEST forum for answers PERIOD!!

Valves haven't been checked yet but are on the TO-DO list.

How do I keep it on a 45sec timer? Cycle it twice or is there another way?

I will to the 'night time' glow-in-the-dark check ASAP as well.

One other thing, is there as quick way to tighten the alt. belt? (The adjustment bolt has seen better days.)

Thanks again!

I forgot to mention, this is starting it from an unheated underground garage.

Thanks!

Where? Fairbanks or Miami?

Do not recycle it... that light is not really connected to the system... in that when it goes off it does not turn off the glow plugs..
So you just turn on the key, ignore the light, time it... then turn the key to ' start'...

Leathermang, is the glow plug light time controlled by the glow plug relay?

I could have been more clear I guess! Toronto, Canada!

So 45 seconds is the standard cycle time for the loop plugs?

I have them on a manual pushbutton switch (PO modification) and have been experimenting with different cycle times. It seems to start best with 90 seconds when it's well below freezing, down to about 30 seconds in the summer. Does this sound right?

The relay does control the time of the light to a very limited extent. You might get another 7 seconds in the bitter cold. But, the relay remains engaged for approx. 35 seconds, independent of temperature and independent of the light.

So, use whatever time you need.........up to the full 35 seconds........to get a smooth start.

What I am going by is the Factory Shop manual saying that the glow plugs continue to heat up for about a minute ... they even give the temperatures they expect them to get to... and being conservative...as usual... I suggested he keep it engaged for 45 seconds...

While I've never actually timed a 616, the statement "about a minute" translates to 35 seconds on the SD and the SDL.

The loop plug light in my 77 300d stays on for an eternity compared to my 85 pencil plug relay. Then again the light stays on much longer in my 79SD than the 85 even though it has pencil plugs. I've never actually compared the actual times the plugs are energized.