81 300D produces much blue smoke & runs rough for about five minutes after first start of the day. 'Clears up after this and runs very smoothly rest of day 'til it sits for few hours not used - does it every time it is started after sitting for few hours unused. What is most like culprit? TIA

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Wilton Strickland
Goldsboro, NC
91 350 SDL. 81 300D

looks like your injectors are leaking.should normally be black smoke. blue smoke is usually lub oil

Smoke is definitely BLUE. Left car w/independent MB Tech/Wrench several days ago; 'told him I suspect valve guide seals. He says he can't find any prob. w/valve guides & seals. He has also adjusted valves (adjusted last time 1 yr., 4 kmi ago) and checked compression, glow sys. and injectors and found all OK. He mentioned possible prob. w/injection pump. Car runs beautifully after about five min after 1st start of day. How can IP prob. cause oil burning, especially only for 1st five min.?

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Wilton Strickland
Goldsboro, NC
91 350 SDL. 81 300D

Brought car home last night from almost two weeks w/Tech/Wrench. Compression, valve adjustment, injectors, glow sys. are all good. Though Tech/Wrench said he found no prob. w/valve guide seals, I had him replace them anyway. He also reamed glow chambers.

Car still smokes and runs rough first five min. after first start of the day; 'clears up after warm up - cannot ask for it to run any better after warm-up.

Can some EGR prob. cause such as this prior to warm-up???

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Wilton Strickland
Goldsboro, NC
91 350 SDL. 81 300D

TXBILL,

Your're right, this is not normal!! 80 240D I had for 16 yrs. 'til it was totaled almost five yrs ago at 185 kmi never did this, & 350SDL (134 kmi) I've had since then never does it - both have always started with just a touch of the starter & run smoothly immediately with no smoking. The 300D is very embarrasing smoking up the neighborhood every morning!! I really need to find a solution to this!!

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Wilton Strickland
Goldsboro, NC
91 350 SDL. 81 300D

It is possible to have normal compression and have alot of blowby. The top piston ring is for oil control and the lower ones are for compression. I agree it is annoying, but if it runs ok, it is not worth spending the money to repair it. Valve seals are not a problem on these engines, I have seen them replaced only on the newer 603 motors, but their problems are different all together (pistons/rings).

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I think that the bores may be out of round or etched. I have seen this before. When the engine gets warm, the pistons swell to take up the slack.

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