Good morning. I have a quick question. Does a 1985 300SD have a tachmeter sending unit? I see the sensor at the flywheel and I follow the wire to the diagnostic plug and then the 2 wires disappear under the fuse box. Am I looking in the right place of it? I remember reading that the 84-85 year did not have this. If someone could help me out, it would be much appreciated. Thank you.

David

Welcome to the Forum.

I don`t know if the 85 126 and 123 are the same with the tach. my 300D has the tach pick up sensor at the flywheel also. I thought the cable for it ran to the EGR computer thing that is behind the passenger kick panel. large black box with a large plug on the top. the Egr, the IP has a box on the back side which is the rack position sensor, these send a sig to the black box.

Also there is the OVP relay (over voltage protection) which has a spade fuse in the top. It could be blown, I`ve read this is a problem with the Tach`s.

the diagnostic plug has a cable that runs down to the front crank, but for 84 and 85 doesn`t send a signal to the tach.

http://www.allpartsexpress.com/ShopByVehicle.epc?q=1985-MERCEDES--BENZ-300sd--/--L5--998cc--3.0l--Diesel--Fi--Turbo-Electrical&yearid=1985%40%401985&makeid=MERCEDES+BENZ%40%40MERCEDES+BENZ%40%40X&engineid=1194049%40%40300SD++%2F+L5%2D2998cc+3%2E0L+DIESEL+FI++Turbo%40%40300SD&catid=Electrical%40%40Electrical&subcatid=Overload+Protection+Relay@@Overload+Protection+Relay&mode=PA

Tachometer link threads
Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works