Replaced ISX starter.

[Ivylog]

Bought a Denso R5 428000-4440 starter 3 years ago but mechanic said it wasn’t a replacement because it had fewer teeth than the Delco he took off my ISX. Did more research and it is the correct one because the gear is off center in the hole. Last month the engine would barely turn over using the boost... nothing without using it so time to replace.

Had a heck of a time getting the Delco off as it takes a 16” extension rendering an impact worthless. The Denso is much shorter and only had to reroute the positive cable to make it connect.

Had disconnected all 3 negative battery grounds so tested each battery by seeing if one at a time would turn it over. Each one did and with all three batteries connected, it turned it over faster than ever before even without using the boost. Hard to believe a motor half the size of what I took off spins a 15 liter engine so fast.

[vanwill52]

I had the same experience of much faster engine turnover using a gear-reduction Denso to replace the Delco on an ISC-350 in a 2000 Dynasty.  Measured the current and it was much lower inrush with the Denso and also significantly lower while continuously turning over.  Spins over like a Honda.  Will start in freezing weather without block heater and not even waiting for the "Wait to Start" lamp to extinguish, although that was only a test--I always wait for the "Wait to Start" lamp to extinguish.

I think there is also a gear-reduction starter from Delco, but I know nothing about it.

[Ivylog]

The Delco I took off is a plantary gear reduction starter but not near as good as the Denso. With probably 5,000 cranking amps (boost on) it barely started.

 

[planodp]

Thank you for the information. Just order Denso from ebay $152 + tax. It's going on a ISM 04 Executive.