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  #16  
Old 12-07-2005, 04:09 PM
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Quote:
Originally Posted by Craig
I've found that using too much throttle before it catches can be counter-productive. I usually don't touch the throttle until at least on cylinder starts to catch. Then I use just enough throttle to keep it running. I also turned up my idle a bit to help keep it from stalling when cold.
I tried to turn my idle up but it is making no difference. I've got the nifty little dial on the firewall and it is turned up to the seventh setting and it is still at 650rpm. I think I've got another vacuum leak (notice the use of another, seem to be a common thing on this board)

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  #17  
Old 12-07-2005, 04:30 PM
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Dont use either on these cars. That is a good way to blow the head off.
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  #18  
Old 12-08-2005, 10:23 AM
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It was around 15 below this morning and the 300td started. After reading the manual yesterday which clearly indicated you had to keep turning it over with the starter, I kept the starter engaged for a long time. After about 30-40 seconds it began firing intermittently and finally started up. I had to shut it down immediately because it went to high rpm's because the linkage was stuck from the cold. But it restarted right away. Interestingly, the slight miss which is usually there for about 45 seconds after a cold start was not there today.

I think the trick is to overcome our gasser habits and be willing to keep the starter cranking well beyond what seems reasonable (to me at least), because it't not like a gasser where stopping to give the starter a break and trying again is an acceptable practice. Keeping a diesel spinning for a long time with a starter is heating the engine up and helping it to start. Short bursts of the starter in cold weather are not effective diesel starting techniques. I also kept my foot on the throttle.
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  #19  
Old 12-08-2005, 10:33 AM
Craig
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I'd be a little careful about cranking the starter for 30-40 seconds at a time. Personally, I don't crank for more than about 15 seconds at a time, then give it a rest and try again. I'm not really sure what these starter will take, but IMHO, 30-40 seconds might be a bit much.

You're right about not starting it like a gasser, my wife tends to only let her 240D crank for about 3 seconds before giving up.
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  #20  
Old 12-08-2005, 11:02 AM
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I lived in Fairbanks, Alaska for five years. My neighbor across the stree had a Peugot diesel. He had a heated garage, block heater, and battery blanket. When he was away from home, he just never shut it off. It ran all day when his wife drove it to work.
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  #21  
Old 12-08-2005, 11:07 AM
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Quote:
Originally Posted by Craig
I've found that using too much throttle before it catches can be counter-productive. I usually don't touch the throttle until at least on cylinder starts to catch. Then I use just enough throttle to keep it running. I also turned up my idle a bit to help keep it from stalling when cold.
This is always an interesting discussion and I've got some thoughts on it as well.

If all plugs are working properly, and the starter is spinning the engine fast enough, then, it appears that opening the rack half way is not detrimental. When the engine finally starts, it does so with a cloud of smoke as all the unburnt fuel that was injected finally lights off.

But, I've experienced marginal situations with two bad glow plugs. Temperature about 25°F. or so. Begin to crank it with no added fuel and it tries to crawl up to an idle with some cylinders firing a some not firing. Naturally, the temptation is to provide more fuel. But, the moment you touch the pedal, all firing ceases and you are back to full cranking again.

So, my thought is that the engine is right at that marginal area where it can light off a small amount of fuel if you wait long enough and do not let go of the starter. But, if you add any extra fuel, the fuel sucks the heat out of the cylinder and all chance of lighting it off disappears.

It's somewhat of a quandry. If the plugs are working properly and there is good compression, the extra fuel would appear to allow it to start faster. But, a marginal engine requires NO FUEL if success is to be achieved.
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  #22  
Old 12-08-2005, 11:17 AM
Craig
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Quote:
Originally Posted by Brian Carlton
But, I've experienced marginal situations with two bad glow plugs. Temperature about 25°F. or so. Begin to crank it with no added fuel and it tries to crawl up to an idle with some cylinders firing a some not firing. Naturally, the temptation is to provide more fuel. But, the moment you touch the pedal, all firing ceases and you are back to full cranking again.
That's exactly the situation I was thinking of. It feels like it "floods" if you give it too much fuel before it really gets going. Then, when it does start, it blows a bunch of black smoke, indicating there was a bunch of unburned fuel in at least one cylinder. I guess I need to bench test all my GPs, they all have about 0.5 ohm (cold) but it's acting like one or two are still weak.
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  #23  
Old 12-08-2005, 11:23 AM
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My impression is that there is an initial 'flooding' for a few seconds and the starter slows down, but then it seems to fire easier afterwards.
It would be interesting to find some MB technical data on how long it is appropriate to use the starter.
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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
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  #24  
Old 12-09-2005, 01:25 AM
Brandon314159
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I have noticed the exact same as Brian posted...

1 working glow plug...if you put her to the floor you are dead

The 240D? I just crank it with the fast idle set and let her go...fires up in no time. I think it has a weak plug or something...actually starts real well into the high 20's and probably lower...has a block heater but I didn't plug it in just wanted to see how well she started.

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