MT-480 Setup tips

[reklund]

Hey guys-

I've been struggling for 2 weeks now trying to get some timing readings on my truck. I've tried 2 separate MT-480 units, with 2 separate magnetic pickups, and can't get ANY RPM reading from either of them. I cleaned my harmonic balancer with emery cloth, cleaned the groove with a litlte pick and some brake cleaner, and made sure I'm getting good 12v+ power to the MT-480.

I believe that the optical side works fine on the meters, as I can get the degree meter to full field, but can't get any tach function. According to the troubleshooting tips in the instruction manual for the MT-480, that is because the RPM signal is no good.

I tried moving the probes until they touched the balancer. I tried backing them off a little so they didn't quite touch. I tried backing them out until they were flush with the inside of the holder. I wiggled. I jiggled. I cleaned the contacts in the quick disconnects.

I know Mel's got lots of time behind one of these meters...maybe he's got some tips? What is the likelihood that I've got 2 non-functional units sitting in my garage? Should I give up and buy the Blue-Point pluse adaptor and be done with it?

Any and all tips or constructive criticism is appreciated...

Ryan

 

[RLDSL]

I bought one of those things with the same problem I monkeyd around with it trying all the usual fixes for two weeks before pronouncing the magnet probe dead ( after testing all the componants on the circuit board ). It's pretty common on them . The tip was ground down on mine before I got it.
I'm going to blow the money on a Ferret . They have them pretty cheap here :http://www.tooldiscounter.com/ItemDisplay.cfm?lookup=FERV765-01

-------Robert

 

[Dalvaras]

I bought one of those things with the same problem I monkeyd around with it trying all the usual fixes for two weeks before pronouncing the magnet probe dead ( after testing all the componants on the circuit board ). It's pretty common on them . The tip was ground down on mine before I got it.
I'm going to blow the money on a Ferret . They have them pretty cheap here :http://www.tooldiscounter.com/ItemDisplay.cfm?lookup=FERV765-01

-------Robert

so does yours have a good luminosity probe because mine tach pick up works but I have no lumi probe.paid 5 dollars at a local auction house for it so I did not mind that it had no probe I figured I could find a good used one or just spend the green on a new one.

 

[reklund]

one of the meters that I have here has a good lumy probe...

 

[93_E_350]

Have you tried it on another diesel?

 

[reklund]

No, I've only tried these two meters on my truck. The meters history is a little sketchy, as in both owners haven't seen the meters work. They were purchased on ebay but appear to be in good condition.

Ryan

 

[RLDSL]

so does yours have a good luminosity probe because mine tach pick up works but I have no lumi probe.paid 5 dollars at a local auction house for it so I did not mind that it had no probe I figured I could find a good used one or just spend the green on a new one.

The lumy probe and the meter on mine appears to work according to the troubleshooting manual for the thing. The part of the meter that the lumy probe triggers was doing what it was suposed to, but the magnet probe is shot. I was just down monkeying with the magnet probe to see if it has a bad solder in the connector, so i cut the wires between the plug and the magnet probe and could not get continuity with the probe on metal, so the magnet probe is definitely shot, but the rest looks good.



----------Robert

 

[Agnem]

I have a 1480 which I believe is just a digital version of the 480. If it works like mine, you will get a tach reading from either probe, but no timing if both are not working. Definitely my usual approach is to verify that I have good RPM's from the tach sensor before hooking up to #1. You can check the probe with a volt-ohm meter for continuity, although I can't tell you what the proper value is. If it shows infinite resistance, it is definitely bad.