Low top speed, foul smell , sluggish

[PSB]

Hi,
My 230 auto was a  few months at a knowledge classic car mechanic ( albeit mostly a jaguar garge) to get it running again after 8 years of unplanned storage. Then a 100 miles later another guy to have the gearbox changed ( previous one suddenly started to slip and would appear to be in N  at 2000 rpm, not go over 2000 rpm)  and then Mercedes classic center in Portugal for interior and another mechanical tune up.....12 months and only 200 miles.
now the past couple of months I've been driving it weekly for about 1 hour straight with a mix of urban and freeway. I haven't driven another pagoda so I can't compare but here is what I "see" and some questions ?
1) fairly sluggish car specially from zero ( weather I floor it or not ) but seems consistent with comments I found while searching the forum
2) very limited top speed - on the freeway at at 3600rpm it gets to 60mph but a a struggle to get to 70 ( 4 Kms into the freeway) and only got to 80 with the benefit of a slight downhill and now in the high range of 4xxx RPMs
IS THIS NORMAL ?
3) no visible smoke but a very foul smell left in the garage when I start it up. What could this be ? Co2 emissions were in the high 600s co2 /mg  according to a test .
4) seems to be doing high  side of 20 liters per 100kms
Normal due to age and trying to drive it fast on the freeway (and also slow traffic mix) ?
Excuse the "essay" . I'm a zero, mechanical wise....
Regards
Pedro

[rjmarco]

Hi, Pedro.

I have a 1965 230SL with a manual transmission.  The performance of my car has always been good even thought it was in need of an engine overhaul which I have had done recently.  Never sluggish. 

I do mostly freeway driving in California.  I can tell you that the car accelerates well entering the freeway and easily cruises at 80 mph at ~4000 rpm with room to easily go to 90 mph.  My fuel economy has been around 19 mpg and occasionally gotten to 20 mpg.  The car did regularly use oil, say a quart every 300 miles, but I'm hoping that my engine rebuild has corrected that. 

Prior to my engine rebuild, I got blue smoke from my tailpipe when revving it out of first gear.  I've never had a foul odor in my garage.  However, I have had gasoline odors in the garage when I had found that my gas tank vent lines had deteriorated.  Once replaced, the odor disappeared. 

I hope this helps. 

Regards,

Rich

[Tyler S]

First would be to check the usual tune up items but this type of power loss sounds like the timing is not advancing.
Check the distributer advance by connecting a timing light. The timing should increase (advance) ~ 30 degrees or more at 3000 rpm.
It is also possible the throttle linkage was not set up correctly for the injection pump. There is a procedure in the tech manual for full members.

[ja17]

Make sure you are getting full throttle. When the fuel pedal is all the way down, the venture intake must all the way open or close. Good advice on checking timing and doing the linkage tour.  I would also check to make sure  your "kick down" (transmission downshift at full pedal) is working.

[Cees Klumper]

Your car definitely needs a knowledgeable person to go through. Top speed should be close to 190 km/h, consumption 8 km/l at most, and acceleration should be 'quick'. There are a lot of variables but if you yourself or a mechanic are willing to put in the time to go through all the relevant tuning/diagnosing info on this site, you will be rewarded with a much better running car.

[PSB]

Thank you for the replies. I need to collect this info do some more search on this site and give some thought on how to proceed ...I've paid 3 bills over the last 3 months (over 25k euros) and all , including MB classic center , included some engine work and definitely a revision and  tune up as I was never 100% convinced . All say the previous work was not well done but nothing has improved.

Regards
Pedro

[Tom in seattle]

I’m sure no “go to” guy but have learned a lot from this website.  My 250 was a dog but I have used the “linkage tour” and “starting tour” and tune-up guidance to great advantage.  I also converted to electronic rather than mechanical points.  In a modern car a tuneup is a change of spark plugs at 60,000 miles.  Not so on this old technology.  I strongly advise you become a FullMember and get involved in self discover.  I agree that ignition timing is a big problem for you, but the interaction of the mechanical injection pump and separate air delivery components are difficult to manage.  It is really possible to make some intuitively wrong tuneup decisions on these cars after they have sat for years of neglect.