I am swapping an om617 turbo into a 83 Toyota 4x4. I am looking for a way to adapt a tach. Does anyone have any ideas besides using the factory benz unit?

Thanks.

There are quite a few options available. Since there is no spark with a diesel, the standard tachs will not work. There are several ways to get a tach signal on a diesel including injector lines, alternator, VR sensor, optical sensor and even mechanical hookups.

One of the more intriguing ones is this - www.youtube.com/watch?v=HhLPAPZxNsM

Do a Google search on "diesel tachometer" and you'll find a bunch of others one or more might be viable options for your application.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

Go read about my 4BT swap into my 2000 Dodge Dakota. I got the tach to work. You can find it on the 4btswaps dot com build forum.

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daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more

I have a MB Electronics upgrade tach amplifier in my 300TD, works great. It looks like they have a solution for engine swaps here:

OM617A Tach Amp for Engine Swap Applications

Other people have also used Tiny Tach. When I do my swap I would like to make the stock tach work.... I bought a 1986 Jeep Comanche last march that is awaiting a 617!

Design Technology, Inc., Home of the Tiny-Tach - Diesel Tiny-Tach Tachometer

Attached Thumbnails

 

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1983 300TD - 202k with 5 speed Getrag conversion

As listed in my project thread (I think) the Monarch photo tach is the cat's - um - pajamas. Mine is an ACT1B, 12 volt. They are $249 + shipping but it's the last tach you'll ever need to buy. You can move it from vehicle to vehicle with the addition of nothing but a piece of reflective tape on something that rotates, plus 12VDC power. Also usable on electric motors or anything else that rotates. This is a lab-grade instrument and is accurate to 1 rpm - or you can order it with more pulses per rev, add more pieces of tape and get accuracy of 1/2 rpm, 1/4 rpm, etc. Not needed for engines.

Dan

Whats wrong with the mb unit?? I installed an mb tach using mb sensor on my '84 6.2 diesel blazer. I had to replace the water pump one time & saw that the harmonic balancer had a small slit machined in it for a probe for checking rpm. the slit causes a disruption in magnetic field (very slight) same on mb's with sensor on front of motor. (I dont know about newer (85's+?). Anyways, while radiator, fan, etc were out, & new pump installed, I made & mounted a bracket on one of the w-p bolts to hold the mb sensor. Got power (always hot + switched) from glow plug setup next to which I mounted the mb tach amplifier (tach from inst panel, sensor, amp & mount bracket all from Ecology, about 30 bucks) Works like a charm.
Pretty much any motor with that slit on the balancer ( a LOT of motors have one, a LOT of chevy's do for instance, inc. gassers) will work with this method.
-c-

What if my car has a diagnostic port? Can the tach amp upgrade that was posted above still be used?

Link please. What you getting for fuel economy?

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked