My '87TD starts just fine, but the first start of the day produces a very noticeable skip and naturally the blue smoke associated with cylinders not burning the diesel. Once the engine smooths out, the blue smoke screen goes away.
Any ideas? I haven't checked the glowplugs yet. It's raining out right now, so I won't get to it today.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

Sounds like an air leak in the fuel system. How are your return lines?

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1985 300 TD 448K
1984 300 TD 278K

1983 240D euro 240k
1994 f-250 idi turbo 330K
1986 f-350 IDI
1987 F-350 IDI

1985 JD 1050 4wd
1965 IH 3660

I have the same problem with my 83 CD and I believe it is due to worn valve guides causing oil to leak down into the cylinders. I would welcome other ideas however.

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83 300CDTurbo 307,000
2005 Honda Element 266,000
56 Nash Ambassador Country Club Special 34,000(under restoration presently)

http://www.peachparts.com/shopforum/car-audio-multimedia/125099-123-install-extreme-dynamat.html

The above are valid ideas, but check the glow plugs first! Then work your way to the other stuff.....

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Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Kindly post your start procedure........

I've reported in the past a number of times about 'hesitation and misfires' upon start up in my 85TD. I've since noticed an important correlation. It does it while the SLS is building pressure and stops once the system is pressurized. I figured this out by having my foot on the ground while I started the car. So in my case, I have a suspicion that the problem is caused by the load the hydraulic pump is putting on the motor at idle. If I start the car, briefly run it at about 1500-2000rpms for a few seconds to build SLS pressure quickly, then bring it back to idle it won't hesitate. If I let it slowly build pressure by just idling, it does the hesitation thing until the system is pressurized which takes longer at idle.

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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

Start procedure is simply wait for the glowplug light to go out, crank. Cranks over fine. This blue smoke and "skipping", "misfiring" etc., is more sever when it's cold. During this past winter, I only had to plug her in once. That was when it was 5 degress. On mornings when it was 15 degs, she cranked over with no problem, but of course got this skipping. Which I took as a cylinder or 2 not firing until the heat from the adjacent cylinders heated up the non firing cylinders. I have very little smoke when accelerating, when the turbo spools up. The smoke I get then, is just whisps of gray smoke. Yesterday when I started her for the first time, it was about 50 degs. She did her usuall skipping and had blue smoke. Though the skipping didn't last as long as it would if it was colder out.

My initial thought/fear was a compression issue, since diesel run on it. However, since a compression doesn't just fix itself, and this skipping does go away, I dismissed that as being a problem.

Hence my posting this problem. Looking for ideas.

I will, when the rain lets up, check the glowplugs.

__________________
1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

Try this first:

Turn the key to glow.

Ignore the glow-light and wait until the glow-relay drops out (indicated either by the click under the hood if you're used to hearing it, brightening of the dome-light, or if you hear the gentle whirr of the little blower behind the glovebox: an increase of pitch/speed of this blower. Should be approx. 30seconds.

Immediately start the engine.

If this cures your cold-start misfire/smoke, you simply aren't glowing long enough. This indicates one or more of the following:
- Aging glow-plug relay light timing circuit (turning off the light too soon)
- Weak glow-plugs (aren't as hot as they used to be)
- Weak battery/alternator (not able to produce the volts @ amps that it should = not as much glow heat)

If it doesn't change your start, you can test the resistance at each glow-plug by un-plugging the large plug at the glow-plug relay to look for a bad glow-plug. If your glow light is operating normally, it is likely only one of glow-plugs 2-6 completely bad, or could be more than one just weak.

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Gone to the dark side

- Jeff

Just checked my glowplugs. With one lead of my meter connected to the negative post of the battery, I checked each glowplug via the connector on the relay box. I got .8 ohms with the meter set at the 200 setting, which on my meter has a audible beep. Every glowplug read .8 except one, which read .7

So, with that, there is no obvious culpurt/reason for an initial rough, skipping idle.

The fuel lines to include the overflow lines are bone dry.

Could it be a compression issue that some how fixes itself? As I mentioned earlier, this skipping is worse the colder it is. It also goes away as the engines idles. Earlier I started her up for the first time today and she skipped a little, for maybe 5 secs., with only a trace of blue smoke. It is 50 degs. out. The engines runs fine otherwise, the turbo spools up just fine, etc.

__________________
1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

Read post #8 and follow it.

Hate to say it but I would say there is a good possibility of borderline compression on one or more cylinders. The reason it goes away eventually is because diesel engines operate on "the heat of compression". When the cylinder is cold and low on compression it just does not generate quite enough heat on the compression stroke to fire the mixture properly/completely. As the motor runs and warms up the cylinder now has more heat and the mixture starts to fire properly. It is also very possible that you have an injector or two with bad spray patterns or low breaking pressures which can cause the same problem.

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1982 240D auto
1978 300CD auto
1985 300D auto
1983 300TD auto
1984 Porsche 944 5 speed
1973 Opel GT 1900 4 speed
1967 Chevy C30 350 Sm420
1973 Mustang Grande Convertible 302 C4
1981 VW Pickup 1.6D Turbo 5 speed
1983 Rabbit 1.6D Factory Turbo 5 speed
Plus parts vehicles...

also everything shrinks when cold, so the piston rings may not be making a good seal with the oil compartment thus leading to loss of compression. but the rings expand after a little heat is applied and you have good compression again. but i would still follow post 8's procedures before you worry about compression.

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Current
2006 E320 CDI, 57K bought at 67K "Liesl"
1986 190E 2.3-16, 198K bought at 56K "Brigitta"
1987 300TD (Chuggin Along), 292K "Friedrich"
1995 E320 Wagon, 200K "Louisa"

Past
1987 300SDL, (sold) 125K, bought for 1$ "Kurt"

The '86 behaves the same way and it's the nearly the fastest SDL on the board (10.7 seconds)and it gets 29 mpg.

The problem is old and tired glow plugs.

There's a reason Mercedes added after-glow to their diesels.

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1987 300TD 309, xxx 2.8.2014 10,000 mile OCI


Be careful of the toes you step on today, as they may be connected to the ass you have to kiss tomorrow. anonymous

“Be who you are and say what you feel, because those who mind don’t matter, and those who matter won’t mind.” Dr. Seuss

I have the exact same problem with my 87 SDL. I think it more likely a glow plug/ relay issue. In my case it helps when you let the glow plugs cycle a couple times. As mentioned before the timing might be off, or bad glow plugs. I would try cycling yjr glow plugs two or three times and see if that fixes the problem.