Would anyone know how to put a tach on a 1st Gen. mine doesnt have one and i had to replace the harmonic balancer. i got one that doesnt have a groove in it. most likely off a newer 2nd gen. is there any way to hook up an aftermarket tach to these engines?

Thanks
Nick

 

Nick,
Have you ran the engine since you replaced the balancer? There is a crankshaft position sensor that needs that groove to work. Are you still running a PCM or did that go away in the conversion?

EDIT: After I posted this, I got to thinking about it - I'm not sure the early 90's had a PCM setup like the 91.5-93's had so the above may not apply.

 

no not yet, i have to wait until i can get the tranny in first. and it didnt havea tach on it before and there wasnt anything near the HB to read off of. plus i have a few otherminor things to do and since im still in school i have ot wait for each pay check to buy the necassary parts. so im not sure since there wasnt one before i hope it works. thankd again
Nick

 

just took a look at the truck, there is nothing near the HB besides the belt and other pulleys

 

If the truck has a crankshaft position sensor, it is usually located at teh top of the HB and is a 1/2" diameter or so cylinder that is mounted so the air gap from it to the HB is about .050.

Like I said, I'm not sure if the early 90's trucks had one.

There is a small electronic tach called a "TinyTach" that uses a small clamp on one of the injector fuel lines to generate a pulse that fires the tach. The tach is a small rectangular housing about 1.5" tall and 2" long with a digital display. Edit: Runs off truck battery or external 9volt battery. Cost is only $65 or so. This is an alternative for a full size tach. Find more info here:

http://www.tinytach.com/tinytach/diesel.php


I have one in my truck because the leads for the tach in my 93 would not work. The tiny tach is great for setting idles and stuff because it gives an exact reading. It is right on with the big OEM addon tach I now have, turned out the trigger problem was in the PCM.

 

The easiest way to do it is to get an alternator tach from AutoMeter. It uses a probe that straps on the alternator.

 

My son's '90 had the solid V Damper. Isspro has a Tach that uses two small magnets on the damper and a sensor that you mount on the pan to read them. I've used them and they work fine

 

Thnaks for the info. i was looking into an autometer and didnt really know what to expect. but i would like to stay cheap. but i know it doesnt have one for the HB because there isnt anything to read a pulse on it so i think either the alternator or tiny tach. thanks for the help.

Nick

 

so i thought i had the solution. my brother is putting a 12v in his Ford, he had the sensor and balancer, so we were just going to swap since i had a HB off a newer truck. since i have a different pulley on my truck and it covers one of the bolts to put the sensor on it wont work. and im glad i took mine off because come to find out there is a huge crack in mine so we have to go to the guy he got his and have him give me a new one. so i think im gonna go with one of those isspro tachs. i just hope i can get a 3-5 inch tach.

 

I pulled the following from TDR. The link below is from ISSPRO's site and it shows the harness. It's simple to make!!!
http://www.isspro.com/proddetail.php...73fe45cbfd0d8a
Hope this helps,
Mark


Quote from TDR:
Outer black wire on the under dash tach connector is ground, this goes to the - screw on the tach.
Inner black wire on the connector is switched 12 VDC, this goes to the + screw on the tach. NOTE: remove the 24 to 12 volt
resistor from this terminal, and wire straight to tach.
Grey wire on connector goes to the S (signal) terminal on the tach. The harness instructions tell you to use the line with the
filter in it (white), mine did not work this way, I had to wire it without the filter (yellow). Orange wire on connector is dash light power, this goes to the spade connector for the lights.

I talked to Don in the tech dept at Isspro ((888) 447-7776) and mentioned that it would be nice to get instructions with the
product...... So give him a call if you still have problems.
__________________
Dale Rittenbach
93 W250 Clubcab LE, Auto, 254K, Stock muffler hooked up to a 4" tailpipe, BHAF, Isspro gauges in a second gen dash
mount, rockrails.