Driving your car hard

[Bearcat]

I have a 280SL 1970 and have put a new exhaust system in her and ever since the car just wants to be driven hard. The new system is obviously less restrictive and hence more power. Together with the roof down all I want to do is gun the car with the glorious rasping sound it makes. The engine has never had any major work on her in 34 years....is it going to blow up or is it a tribute to merc on the engines they USED to make.( a loaded question, none the less I would like your feedback)

[ja17]

Hello bearcat

A healthy engine loves to be well exercised. The key words here is healthy. Good oil pressure, good timing chain, good compression, good "tune" and good maintenance are some of the benchmarks of a healthy engine.

The cars that are used and exercised seem to stay healthy for a long time. Exercise will not fix a sick or damaged engine.

I hammered one of these engines in a SCCA Pro Rally car for years, (extended high rpms and high speeds ) and never had an engine mechjanical failure.

Two points of concern; make sure your verticle timing gear bushing is good and make sure the upper oil filter seal is not missing. Store your car with clean oil and avoid extended periods of inactivity, drive it.

Happy motoring!





Joe Alexander
Blacklick, Ohio

[Naj ✝︎]

Joe Alexander,
Please explain which one is the vertical timing gear reffered in your post?
naj

65 230SL
68 280SL

[ja17]

Hello Naj,
I think you have done this job  as I recal. Here are some photos;

Download Attachment: removal of verticle gear.jpg
60.06 KB
Download Attachment: Verticle gear assembly.jpg
30.98 KB

Mercedes refers to the bushing as a "thrust piece" or "sleeve".

Besides driving the tachometer the gear also drives the oil pump!
If the bushing or the gear fails you may suddenly loose all oil pressure and the engine may continue to run until damaged!

There is a way to easily check the condition of the gear and bushing by only removing the tachometer cable at the engine. This was covered in an earlier post. If anyone needs the information we can bring it up again.

Joe Alexander
Blacklick, Ohio

[Naj ✝︎]

Thanks Joe,
Yes I've checked and corrected this on both cars!
I had visions of some chain driven gear  :oops:
Here's the thread (for those who missed it earlier)


http://index.php?topic=443&whichpage=2

Thanks
naj

65 230SL
68 280SL

[Ben]

Well as you know I drive mine all the time and I regularly excercise it on the motorway cruising at over 5000RPM sometimes. But I do change the oil every 2 months and I swear after a long drive the car starts, idles and runs much smoother !

Go for it !

Regards,
Ben in Ireland.
'64 230SL 4sp.
'03 CLK Kompressor

[Mike Hughes]

Joe -

Thanks for your exploded view photo with part numbers!  I, to, am having an oil leak at the tach drive on my 230SL with 75k and thought a little preventive maintenance might be in order as it sounds like a leak here might indicate wear below.  I went across the street to the M-B dealer and ordered the thrust piece, rubber o-ring, aluminum coverplate ring (just in case, it was under $4!), and seal.  The thrust piece is about $91 and the total for all parts just over $100.  The parts guys really appreciated the photo detail as it made their search much easier!  The part number for the thrust piece remains the same but all the rest of the part numbers have been superseded:  621 050 05 06 is now 007 997 73 46, 126 990 01 04 is now 126 990 01 40, and 120 261 00 80 became 115 274 00 60 and is now 621 997 00 40.  Replacing these items looks to be fairly straightforward.  I'll report back after the parts arrive and have been installed.

- Mike Hughes  -ô¿ô-
  1966 230SL Auto P/S
  Havanna Brown (408)
  Light Beige (181)
  Cream M-B Tex (121)

[Tom]

Mike,

Joe walked me through this replacement and it is not hard.  One word of counsel-don't force the new thrust piece into the opening.

I took some fine wet sand paper and sanded the side of the new aluminum/bronze thrust piece to eliminate any machine marks.  I then put the piece in the freezer overnight.

Next day, I kept the piece in a cooler with ice while beside the car to keep it cold.  I then put some grease on the piece and inserted it into the opening.  Fit snug but nice and I did not have to force it.  Really important to line up the hole on the side with the opening for the bolt that secures the piece.

I know this sounds like over kill, but I destroyed the first bushing by trying to force the piece into the opening.  The 2nd new bushing would not go in very easily, so I e-mailed Joe who advised the above procedure.  Cooling the piece makes it ever so smaller and allowed it to fit in the very tight opening.

Best,

Tom


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1971 280sl Tunis Beige Metallic (restored & enhanced)
1971 280sl Tobacco Brown (low mileage stock)
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[ja17]

Hello,
Thanks for the new updated parts numbers Mike. I will have to update my photo with these numbers soon.
Tom, sorry to hear you had some difficulties with the first bushing. They usually slide in and out without difficulty and without freezing them. You may be able to salvage the brass endpiece from the first bushing. It should come out and you can use this to restore your original bushing since only these brass endpieces wear. Try a little heat this time.



Joe Alexander
Blacklick, Ohio