hooking up inginition wires on a xr-700.

[ch53mechwest]

I have a 1978 datsun and I recently purchased the crane xr-700 and I hooked up everything and i can't not get spark. how is the 1978 datsun ignition wiring hooked up compared to the 1977 datsun. becuase i have a 77 wiring diagram and some stuff the 77 has the 78 doesn't. like i can not find the transitor resistor that is suppose to go to the coil. well please help me

[vercingetorix]

Check the tech articles here: http://zhome.com/

and do a key word search of this site as well, its probably here somewhere.

Luck,

H Houghton

You can try Crane tech support, but they usually reek.

[WingZr0]

Thread Dredge here, I got customer asking for a replacement Tach for a 1/72 240Z. Says he installed a Transitor Ignition and now his tach don't work. Anyone know what this transistor ignition thing is or do he just need a new tach?

Edited March 4, 2010 by WingZr0

[fiveleaf]

Crane xr700 manual

http://cranecams.com/pdf/90002000a.pdf

(Crane is back in business, by the way. Their customer support is open.)

1978 (280z) wireing diagaram attached. With these two documents you should be able to figure out your wireing issues.

Are you using an aftermarket distributor, or a Capacative Discharge (e.g. HI-6 or MSD) ignition box with this unit? This will affect which wires go where from the xr700.

Found this awhile ago and saved it in "wireing diagarams"... just because you never know.

78-280Z_wiring.zip

Edited March 5, 2010 by fiveleaf
Add the attachment

[fiveleaf]

Thread Dredge here, I got customer asking for a replacement Tach for a 1/72 240Z. Says he installed a Transitor Ignition and now his tach don't work. Anyone know what this transistor ignition thing is or do he just need a new tach?

I'm sure someone else can clarify, but the 240z tach is incompatible with many after market ignitions (and distributors?). Something to do with a current sensing tach and an output from the ignition that is designed for a later system. Magnetic comes to mind. I would actually like to know more on this myself.

I needed a tach adaptor after the HI-6 and unilite.

If his system is stock, and he's willing to take the dash off himself to change the old tach out... there is enough information on this site to help him rebuild his old tach. Here's some info on what usually fails and a wireing diagaram.

Mine still doesn't work. The tach is beside me. I'll post pictures of the rebuild in a new thread after I finish.

I have an early tach schematic I will post after I get it scanned. It’s just a very basic two transistor astable (one-shot) multivibrator circuit that drives the meter coil. The transistors are type 2SB189 (PNP 25V 250mA). Looks like you can still get them: http://www.ceitron.com/semi/ceitoshiba.html

Edited March 5, 2010 by fiveleaf

[vercingetorix]

I had an xr700 and a stock point set up and it worked fine,I had to settle my wiring issues here because Crane customer service was hopless,they blamed the tach, TCZC solved the problem. I don't know about a '72 however mines a 9/70 but I bet the answers here somewhere.

[WingZr0]

Thanks guys, the guy's in the Soviet Union and sent a message out the blue. I'll relay the info and suggest he come visit the site as this is a bit out of my league. Wiring, oh the horror .

[fiveleaf]

I'm using the Crane xr700, but triggered by an HI-6 box. Distributor is from Mallory, only I've forgotten where along the line I needed the tach adaptor.

Someone's got to know what I was talking about with the current sensing tach that does not work with the newer (pulse? magnetic?) imput.

EDIT: I looked up the crane tach adaptor because this was bugging me.

"...for use with pulse or current sensing tachometers that will not function correctly when connected to..." a magnetic output.

Edited March 5, 2010 by fiveleaf

[ChrisZ]

Go search for member albhl, he made a adaptor.

Chris

[fiveleaf]

Just realized this thread is 6 years old. Crane and Mallory also make adaptors.

[WingZr0]

Yeah, like i said, "Thread Dredge" . Get this, the guys out in the ocean off the coast of Brazil on a Siesmic Boat right now! Guess they studie earthquakes. Anyway he's going to have someone email some pics of the ignition box and write down the make and part number. Also says the distributor is factory and was asking about MSD PN8910 Tach Adapter FWIW. Will report back once I get those pics.

Edited March 6, 2010 by WingZr0

[alhbln]

Someone's got to know what I was talking about with the current sensing tach that does not work with the newer (pulse? magnetic?) imput..

The tacho which was installed until late '72 (also called 'four wire tacho') is current triggered, e.g. it measures the current going to a small wire loop in the +12V feed to the coil. The current is picked up by a small internal coil and then amplified by two germanium transistors (see circuit by zcarnut above).

Unfortunately, this setup will only really work with an inductive points triggered ignition setup with less than 4A primary current. With a modern transistor ignition you would need to recalibrate the tacho due to the higher primary coil charge (typically 4-8A). A CDI or EDIS setup wont work at all, as in a CDI setup there is less current but a much higher primary voltage, and EDIS uses a wasted spark setup with multiple coils.

After trying out different approaches and adapters, i resorted to build my own adapter, which is triggered by the points signal to the transistor ignition or the square wave signal from a MSD, Mallory or Crane CDI and then injects a 500 mA square wave into the tachs transistor amplification. Its easier to install a modern tach but i wanted to retain the original look after installing a Megajolt mapped ignition.

http://www.dinoplex.org/tachoconversion/

Best,

Adrian