MT 480 Luminosity Probe

[Topmech]

I got an MT 480 the other day, it came with one probe. There are no markings on it. It will fit and work on my 6.2 but I don't know if its the right one or not. My timing shows 9-13 degrees btdc at idle. I've been driving it like this for 5 years so I don't think it is right. Does anyone know what the differences are between the probes, have measurements or anything.
Thanks
Dave

[britannic]

What offset are you using and are you sure that the magnetic probe holder is correctly positioned and not bent or offset outside of specs? The lumy probe wouldn't make that much difference unless it was very dirty or leaking.

[ 06-02-2004, 09:12 AM: Message edited by: britannic ]

[Topmech]

20 degree offset, guess its possible probe could be bent but dosn't look like it. I know they had a probe for a ford and one for gm, I figured I might have the ford probe. I suspect timing is advanced some from the engine sound but it seems like it would have fallen apart by now with that much. Do you have a 6.2 probe you could measure for me. Mine is 2 1/4 long, 1 5/8 from shoulder to tip including threads and the narrow part that goes in the cyl is 5/8 inch long.

[Dieselboy]

The 20* offset was intended for the Ford 6.9/7.3 IDI diesels. We use the #3 glowplug hole and the 99.5# offset. The 6.2L probe is the MT161, but the MT160 should work. They're not anything too high tech. It's just a quartz lens within a glowplug body, so as long as the pickup is seeing the combustion event clearly, then it should work.

[britannic]

Ford used the same glowplug body. The MT480 computer isn't quick enough to detect the moment between the lumy and mag. probe triggers (it's just 9.5* of separation) so using #1 is not an option. As DieselBoy says, go with 99.5* and use #3 cylinder or equivalent.

[Topmech]

Thanks I'll try that.
Dave

[Peter J. Bierman]

Tried to use mine last weekend, did not work.
The home made exhaust manifolds leave not enough space for the lumipickup to fit straight on the probe. :mad:
I tried to make it fit by grinding :eek: an angle at the back and make it shorter, but still no luck.
I guess I have it checked with a line pickup for now and ad manifold modification to the things to do list for the winter project :(

Anyway I had some quality time spent with my truck last weekend :D

Peter