tach shaft in engine block help

[65auto230sl]

hi everyone. i'm very pleased to say that after about a month i have my 230 on the road! it is such a fun car and it runs great! thank you all for all your help. i will be posting some pics soon. i was reading the threads and i as well have a tach question. mine is on the other end. the block end. my new engine is out of a 1970 280sel. it does not have the shaft coming out of the engine block that the tach cable runs off of. my old engine does. how do i get it out? i can't figure it out. any help would be appreciated. thanks again. if anybody has a get together planned in the santa barbara/ southern ca area i'd love to be a part!
thanks,
bo

[jeffc280sl]

Hi Bo,

Glad to hear your car is back on the road.  The tach gear assembly must be removed piece by piece as I remember. Sorry I can't remeber more specifics. Search under tach bushing for a discussion on the topic.  I think there are some pictures also.

Jeff C.
1970 280SL 4-speed

[ja17]

Hello bo,

Search "verticle timing gear" for some reason my search function is not working at the moment so I cannot give you the exact web address. Here is a picture of the assembly also.


Download Attachment: Verticle gear assembly.jpg
31 KB

Joe Alexander
Blacklick, Ohio

[saygold]

If you can review (or better, print out the photo that naj attached in the previous posting), follow this procedure:
1.  Loosen the tachometer cable threaded cap and move the tachometer cable away from the immediate area.
2.  Remove threaded fitting #127 060 0046.  Seal #120 261 00 80 should come out with the fitting; if not, lift it out with a pointed tool.
3.  Remove the cover plate aluminum ring and rubber o-ring #621 050 05 06 in the same manner.
4.  Unscrew the 10 mm set screw #000 561 00 81 07.  (When installed, the set screw extends through the thrust piece, so the screw should be totally removed.)
5.  The thrust piece can be pulled up by carefully pulling up the tachometer cable drive rod.  If the thrust piece is stuck, carefully pull up with the tach cable drive rod in a tapping method until it starts to come loose.  (The tach cable drive rod will rotate slightly as it goes up and down due to the vertical timing gear teeth being at an angle to the tach cable drive rod.)  Remove the thrust piece.  I sprayed a lot of WD40 on the top of the thrust piece, and through the 10mm set screw hole in the engine block.
6.  Remove the tachometer cable drive with the vertical timing gear attached.

Please tell me how it worked out!

Ken
230SL (euro, 4-speed)

[saygold]

Oops.  It was ja17's photograph (I used it on mine last spring).

(I haven't gotten around to learn how to edit a posting yet)

Ken
'66 230SL (euro, 4-speed)

[Naj ✝︎]

Bo,
Please note that you must not change this tacho drive shaft spindle from the old engine by itself.
The gears are matched as a set when cut, so the mating gear must also be changed. This is the horizantal gear/shaft that drives the inj. pump.
Also read:
http://index.php?topic=3097
naj

65 230SL
68 280SL

[hands_aus]

The way I read Bo's original post was that there was no tacho gear shaft on the replacement engine currently in the car.

I think he was wondering how he would connect his tacho cable to the replacement 280sel engine.



Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[Naj ✝︎]

Bob,
I believe its basically the same engine as a 280SL. The tacho drive hole is capped off and the oil pump drive gear has no top spindle that drives the tacho.
naj



65 230SL
68 280SL

[Raymond]

Naj is correct.  You must change the gears together.  It is a good time to examine the thrust bushing for wear in the bronze surface where the tach drive shaft rides.


Ray
'68 280SL 4-spd Coupe

[65auto230sl]

okay, i'm still a little confused. i'm going to attempt this whole tach thing this weekend. i'm confused on what gears need to be taken out together. i do appreciate all the info. thank you all very much. i'll keep you posted on my progress!
bo

quote:Originally posted by 65auto230sl

hi everyone. i'm very pleased to say that after about a month i have my 230 on the road! it is such a fun car and it runs great! thank you all for all your help. i will be posting some pics soon. i was reading the threads and i as well have a tach question. mine is on the other end. the block end. my new engine is out of a 1970 280sel. it does not have the shaft coming out of the engine block that the tach cable runs off of. my old engine does. how do i get it out? i can't figure it out. any help would be appreciated. thanks again. if anybody has a get together planned in the santa barbara/ southern ca area i'd love to be a part!
thanks,
bo

[ja17]

Hello bo,

Naj and Raymond are correct. The BBB states that these gears should be replaced in sets. The vertical timing gear and the horizontal gear.  The horizontal gear is driven by the chain sprocket and drives the injection pump, distributor and the vertical timing gear which turns the oil pump, and tachometer. So you can see the condition of these gears is critical.

The bad news is replacement of the horizontal gear is very very complicated. The timing chain would have to be unfastened, the distributor and its housing removed, the injection pump would have to come off, the vertical timing gear would also need to be taken off. Removal of the chain sprocket down in the block is also a bit tricky.

I know changing both gears is best and recommended but I do know several people who have replaced just the vertical gear and have had no problems.

Also one person on this list (Pat in Cleveland, I forgot his list name), modified his sedan gear and added the tach drive to it! So he was able to keep the original matched sedan gears and also use his tachometer!



Joe Alexander
Blacklick, Ohio