7.3L Powerstroke diesel – Rapid cold start reliability

Cold starts taking longer, requiring several glow plug cycles, and also first notice of an oil leak originating from the oil cooler in the mornings. In this video, am running Motorcraft 15W-40 synthetic oil (https://amzn.to/39hTMX8) along with factory glow plug relay and plugs, valve cover harnesses, and a remanufactured alternator.

Batteries are Optima red tops (over a year old, replaced both at the same time) and starter is a non Denso unit purchased retail from an O’rielly’s part store.

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Improvements made for rapid cold starts

10:30 Plumas National Forest, California

15* Fahrenheit (-9.5* Celsius) ambient temperature

Elevation 5900 feet (1800 meters)

Truck now has a brand new oil cooler and gaskets (https://amzn.to/3t3tRui), see my separate write up about this repair, which requires draining motor oil and coolant.

New oil filter and refilled with

• 15 quarts (14 liters) of 5W-40 Shell Rotella T6 synthetic motor oil (https://amzn.to/3sOseAB),
• 8x new Motorcraft glow plugs (https://amzn.to/2Yd6Jeo),
• Napa valve cover gaskets that eliminate the under valve cover connectors, and a
• White Rogers glow plug relay (https://amzn.to/3sW8bjq).

This is a California emissions truck with a factory shunt at the GPR, and the shunt was eliminated with the new GPR by stacking the wire terminals on the GPR post.

This setup has produced by far the fastest, most reliable, rapid cold starts. Batteries are Optima red tops over a year old, alternator is a high output 220 amp unit, and starter is a lifetime warranty unit (non Denso) from a retail O’rielly’s parts store.

With a volt meter in the cigarette lighter of the truck (https://amzn.to/369gKO4), batteries at rest read 12.3 volts.

1. When the wait to start (WTS) light and glow plugs are energized for their duration the voltage reads 10.9 volts.
2. When cranking the voltage drops all the way down to 9.0 volts.
3. Lastly, when the alternator is charging and motor is running, voltage reaches 14.3 volts.