Mine is --in the parts section

thanks for clarifying, charlie! now i expect to go with the harmonic balancer + tach amp setup. just got the driveshaft pieces today so i can take them to be shortened.

You are the man Charlie - good to know.

How different is the tach amp section of the system? On the '84 / '85 W123 is it included in some sort of "computer" like the W126?

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Iam not sure what the W126 has, but on my 85, the black box is about 6 inches wide, 8 inches tall and about 2 inches or so thick. has a large cable connector with 2 rows of pins, maybe 14 or so. (Don`t have one in front of me, just memory) the box gets a bunch of input signals, from the FW sensor, Rack Position Sensor that is mounted on the back side of the IP, and maybe even the water temp send a signal. somehow this box makes the tach work and also the EGR.

In the almost 15yrs we have had this car, it has never had a tach problem. I see the Tach amps on the inner fender being more of a troublesome issue from what I read.

The 82 & 83 240D had a black box also, but picked up it`s signal off the front crank like the 617`s do. it`s box is also placed behind the passenger side kick panel, but much smaller.
It has the large cable from the crank, one wire from the fuse panel, and the one to the spedo speed sensor, and it splits off to the Cruise Control amp box. and finally a wire to the EGR.
Funola, modified his 240D black box so he could install a tach in his 83 240D.

DIY tach for 240D w EGR- easy!

I ripped through the dash`s of 3 different 240`s in the yards chassing down these wires to see where they all went. easy part was pulling the dash. sorting through the spaghetti bowel of wires of the various wiring harnesses where they all branch out.

Charlie

__________________
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

Thanks for the info and link Charlie - sorry for the thread-jack Tom!

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I would split the difference. 240d fw is gonna have more HP less torque. Also I think the farther out the weight is the more torque and less HP you will have.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Now I have a couple of thousand miles on my converted 240D with the 617Turbo. Transmission problems were all solved by the simple change of oil from Mobil One 10-40 to a fresh charge of Mercon Dextron. It was so wonderful, in the first half mile after I made that change, all transmission problems vanished - on the spot or down the road, GONE! Thanks again HUNTER! Now I am running with the light weight flywheel. It does create a lot of resonance under low speed, high throttle operation. So long as I keep shift speeds high it is not bothersome to me. But if I get locked into slow moving traffic, I sometimes have to downshift just to get away from the "BUZZ". First and second gear are no problem. Third is a problem under 30, and 4th is a problem under 43 mph. I think the heavy flywheel would really get rid of that odious racket at those slow speeds. So I downshift, It might coast a little in fuel, but I really think it is a small amount, maybe none. I have checked my mileage on a regular basis and so far it is very steady at just better then 27.5 in my suburban type driving. But what I really am delighted about is the way it drives. It is awesome really in comparison to my 85 300D automatic. It really loves getting out there and getting it on. I run a consistent 10 psi on the turbo and it spools up very fast, much faster then when it was hooked to the automatic. I rather think that light and easy running is because of the light flywheel. It does love to wind up quick and it just sounds awesome on that exhaust. I think it is a real keeper. I really think that where ever possible, a larger clutch and pressure plate should be used. the other day I tried to get the two right side wheels up the wheel ramps. It didn't like it, but it went up. Then I put tried to put the left side up, and that 260 pound driver sitting in the drivers seat had to be lifted also, and it wouldn't do it. I goosed it and it started up, stalled and I gave it more throttle while releasing the clutch and then I realized I had no more clutch to let out and it was slipping. So I instantly shut it off by pushing in the clutch - clutch did smell a little. So I know now that it is easy to overload and I will inspect that good in June when I plan to pull this transmission and try another one.

__________________
Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!

I'm also running a 240D flywheel and mine does the exact same thing. I've adapted my driving style to it the same way you have.

__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

theres a hole drilled in the side of the rings on the 617 sick flywheels-maybe thats what for

Did you read what I posted in post#29.

The 240D didn`t have a tach, and Iam using a FW from a 240D in my 85 300D 4-spd swap. the tach still works as it did with the auto FW. also Iam using the 85 adaptor plate and the Tach pick up off the FW. so there is no magnet or other pick up gizmo.

Charlie

__________________
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

coming back to this thread because it was touched recently, i was concerned to read the above because i tend to drive around town at low RPMs. my 240d flywheel is at the shop to be balanced right now.

would the heavier flywheel really solve this vibration? especially if they are neutrally balanced, i don't see why there would be a difference. (i've read in a few threads that a neutral balance is common but not universal in 123s.)

even with a non-neutral balance, if it's transferred to the lighter wheel and that's oriented correctly, shouldn't the net effect be the same?

OK, flame suit on

Thats balancing.

All the 85 and up tachs (84 190's) pick up their tach off the FW starter gearing using a hall effect sensor.

In todays world it is often referred to as a crank position sensor as well.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

The heavier the fw the more vibrations will be dampened. The heavier fw though will absorb some power on acceleration and decellaration. ONce at a constant speed the weight of the fw does nothing to energy consumption, but will continue to dampen vibration.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

My understanding is that the flywheel is just a store of kinetic energy

Kinetic energy - Wikipedia, the free encyclopedia

...where the kinetic energy is proportional to the square of angular velocity.

The harmonic damper, however, is designed with the intention of reducing vibration at resonances over a range of engine rotational speeds. The resilient rubber part of the harmonic damper is meant to provide stiffness and damping which coupled with the two part masses (in the damper) change the "effectiveness" of resonances produced by the rotating parts in the engine.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

If you disagree that reduced vibration is a benefit of the heavier flywheel why do you suppose MB equipped the 300 motors with it?

And what is your explanation of why my 300 with the 38# FW idles so much more smoothly than an automatic equipped 300?

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.