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Bought a 1995 12 valve Cummins not too long ago just as a project truck. There was a big fuse wrapped in electrical tape zip tied to other wiring. If anyone could tell me what it is and possibly where it goes I would appreciate it.
To me this looks like the alternator wiring loom. Small spade looking thingies go to the brushes, bigger thing on the same hard plastic is alternator output and the free fat end goes to ground if I recall this correctly.
As mentioned that bolts to the back of the alternator.
On a side note air filters bolted directly to the turbo, that suck in the hot air right off the exhaust manifold are a terrible "mod" in my eyes. The factory air box is much better for your truck, with lower temp. air that is filtered better.
Agree with AlpineRam that it is that the alternator loom - however, I have an illustration showing that the free end is alternator output (B+) and the larger terminal on the plastic piece is ground (larger illustration is from FSM/AllData - same terminals, just upside down from each other). If you have a factory alternator, you could (carefully!) mock it up against the back of the alternator to see which reaches the alternator's B+ terminal and which connects to ground terminal. The small spade-like terminals go to field-control terminals and are usually held on with nuts.
Does the truck currently have an alternator - if so, what kind and what's in place for charging control?
GenosGarage has the FSMs on paper - buy once, cry once unless you tear a page or spill something on it... Some people say the paper copy is best for following wiring diagrams.
AllDataDIY has most/all of the FSM info in electronic format - it's a per-year/per-vehicle subscription. First vehicle each year is the most expensive - additional vehicles are cheaper. Its the FSM data and diagrams (printable), broken out and searchable. I have on occasion seen some inaccuracies - something that applied to the gas engines, or an incorrect transmission plug (maybe for the 47RH, where mine is 47RE), but over all its pretty good.
PM'ed you with a link to a source for free, downloadable FSM...
The FSM info is just as important of a tool as a ratchet or multimeter - worth the $, as AlpineRams said.
Well, being in Austria, one ocean away from any chance of a shop that is used to fix these trucks the factory service manual was worth about it's weight in gold. (for the print version)
All the nice hints you get from the internet may not pertain to your year of the truck... but they might just have swapped plus to ground at this model change.
So buy the bugger for some $ (less than a box full of fuses) and do it right for your vehicle.
...Ben
