My starter exploded

This morning, when I started my 1994 7.3 IDI truck, the engine turned about two revolutions, followed by a loud bang. After that, all I could hear was the starter spinning, but no cranking. I pulled the starter out, and it came apart in about half a dozen pieces. When I removed it, I noticed the top bolt, which is notoriously hard to reach, was completely loose. I’m thinking that over time, the starter flexed every time it cranked, eventually causing it to break.

Has anyone else experienced this, or have any other ideas on what might have caused it?

The ring gear doesn’t look great, but it’s probably good enough to keep working for now. I was planning to do a single mass flywheel conversion soon, so I might replace the ring gear then.

6 Likes

Undoubtedly, loose bolts may be the culprit. Apply locktite of medium strength.

Moreover, kickback, as you indicated.

I believe it is difficult to move the timing forward that far.

Alternatively, beginning fluid can be used.

6 Likes

I don’t usually say this, but I recommend replacing the mounting bolts since at least one of the old bolts came loose on its own.

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I should mention that I re-timed the injection pump using the DTI tech time unit a few weeks ago, so I don’t believe the engine kicked back. The truck was running well, I have only had it for a few months and was daily driving it to work last week, covering about 100 miles a day with no problems and getting around 18 mpg.

4 Likes

I did not experience that, but the PO on my IDIT had installed a cheap Chinese starter, so I replaced it with a new Motorcraft gear reduction one that I purchased on RockAuto.

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Most likely the result of flexing bolts that are loose. It won’t take long for a crack to fully break once one starts.

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At least it was the starter and not the block.

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I have never seen that before. It can not be a good sign. :grin: