My new car - already worried... - PeachParts Mercedes-Benz Forum

MercFan · #1 05-08-2006, 12:31 AM

Howdy -

I just picked up my first 300D - it's a 1985 300D Turbo; the car is in a really nice shape. I've purchased it out of town, had a local mechanic there check it all out - few minor things reported but overall he though it was a good auto. I drove the car before purchase and it drove very respectably. Had a decent pickup and it drove really nice on the highway.... so I bought it and trailered it home.

When I got home (vehicle was 'cold') it started ok, but it was a DOG... I mean it had no power to speak of and it felt like it was going to stall... Needless to say I was very disappointed. I don't have plates for it, so I only drove it a bit around the neighbourhood and it seemed to improve a little but it was still really lacking power.

Tell me -is this fairly normal for these cars or is this a sign of some bad things to come?! Again, I did drive it on the highway when it was warm/hot and it performed well.

Your comments will be appreciated as I'm a little worried at this point...

Thanks,
James

OMEGAMAN · #2 05-08-2006, 12:39 AM

Check the hose from the intake manifold to the alda (do a search) if that line is plugged the car will be real slow. PM me if you need a good indy mechanic I used to work with some guys on south broadway they can look after you.

Boardmonger · #3 05-08-2006, 01:10 AM

Turbos can be very slow right after a cold start. My 83 take a good 10 minutes of driving to be at operating temp and once it is it drives very nicely. But out of the garage I just keep the rpm's down for smoother shifts. So the question is how long were you driving it around the block and did it get to operating temp. If it did, check the fuel and air filters, the most common problem. In any case good luck.

Brian Carlton · #4 05-08-2006, 02:35 AM

Diesels are normally a bit cold-blodded when not fully warmed up. You simply have to recognize this and drive them with relative ease for the first 10 minutes or so. Once fully warm, then their performance returns to "normal".

But, realize that you've only got 123 hp on tap........at 4400 rpm.........much less at normal rpm levels. It's never going to perform like a typical 200 hp gasser.

vstech · #5 05-08-2006, 09:33 AM

ya may want to drain it and put in some good 10(or less)W40 and see if it makes any improvement in cold performance. some car salesmen put in 90W

to eliminate any noises or smoking... this would perform this way, the turbo would have hard time overcoming cold 90W oil. and it would be heavy on the rotating assembly...
if the oil drains out quickly when cold, that is probably not the problem... check the alda hose. or the alda selonoid. and the primary filter should be clear, not dirty looking at all. if it is suspect the fuel tank screen. but I can't really see theese causing cold problems, just problems in general... really think it is the oil.
John

mobetta · #6 05-08-2006, 09:34 AM

just sell the car.....to me!!!

MercFan · #7 05-08-2006, 10:47 AM

Quote:

Originally Posted by vstech

... check the alda hose. or the alda selonoid. and the primary filter should be clear, not dirty looking at all. John

Thanks everyone. Can someone tell me (or give me a link) to a good procedure for checking the ALDA - I did a search on the forum and found a lot of people talking about it but couldn't find anything on how to check/service it...

Also, would an altitude affect a diesel this way (would it affect ALDA)?! I bought the car in Kansas and brought it to Denver (over 5K feet a.s.l)

THanks in advance -
James

vstech · #8 05-08-2006, 12:25 PM

Quote:

Originally Posted by MercFan

Thanks everyone. Can someone tell me (or give me a link) to a good procedure for checking the ALDA - I did a search on the forum and found a lot of people talking about it but couldn't find anything on how to check/service it...

Also, would an altitude affect a diesel this way (would it affect ALDA)?! I bought the car in Kansas and brought it to Denver (over 5K feet a.s.l)

THanks in advance -
James

http://dieselgiant.com/mercedesaldaboostsystemservi.htm

MercFan · #9 05-08-2006, 01:04 PM

Quote:

Originally Posted by MercFan

Also, would an altitude affect a diesel this way (would it affect ALDA)?! I bought the car in Kansas and brought it to Denver...
James

Thanks for the lin - what about the altitude factor on the diesel engine and/or the ALDA - maybe something need to be adjusted?!

Hatterasguy · #10 05-08-2006, 04:15 PM

When these diesels are cold they have zero power. When its in the teens I pretty much have to floor the SD to get it moving forward. As the engine temp comes up so does the power.

george d · #11 05-08-2006, 07:20 PM

I think altitude can make a big difference. It was my first thought. I am suprised that someone has not mentioned it, someone who knows much better than I do. The ALDA is supposed to compensate for altitude, but I do not know how much, etc. Maybe someone else will chime in!?!

George

t walgamuth · #12 05-08-2006, 09:19 PM

Quote:

Originally Posted by vstech

ya may want to drain it and put in some good 10(or less)W40 and see if it makes any improvement in cold performance. some car salesmen put in 90W

to eliminate any noises or smoking... this would perform this way, the turbo would have hard time overcoming cold 90W oil. and it would be heavy on the rotating assembly...
if the oil drains out quickly when cold, that is probably not the problem... check the alda hose. or the alda selonoid. and the primary filter should be clear, not dirty looking at all. if it is suspect the fuel tank screen. but I can't really see theese causing cold problems, just problems in general... really think it is the oil.
John

i dont know of any 10w40 oil rated for diesels.

i would look at the fuel and air filters first, and if the primary fuel filter has black dots in it you have fungus in the tank and need some fungicide, available from truck tractor and marine suppliers.

good luck

tom w

tom w

mikemover · #13 05-08-2006, 09:29 PM

I don't really have this problem with my 617 diesels, unless it's EXTREMELY cold out...

I'd check to make sure your glow plugs are good.

Mike

#14 05-08-2006, 10:46 PM

My 617 is pretty doggy for about 30 - 60 seconds if I drive away when it's dead cold. After a minute or two, the power becomes "normal." If the power is still low when it's up to temperature and everything else is OK, consider adjusting the ALDA and see if it helps.

MercFan · #15 05-09-2006, 10:32 PM

Quote:

Originally Posted by Craig

If the power is still low when it's up to temperature and everything else is OK, consider adjusting the ALDA and see if it helps.

I've decided to visit the PRO down the road - someone that was recommended on this forum (Zoie from Foreigh Car Repair in Thornton) - wanna get his opinion on the car's performance... Lord, please don't let him tell me I've got a nice looking car with a bad engine... that would just about kill me...