Slow to start - W900

Sounds fuel related... possibly a starter, but more like fuel is draining back to the tank and is not readily available at prime for starting... I’m not to familiar with the Detroit 60 motor

 

A few things to consider

Batteries could be getting weak.
Fuel check valves.
Lift pump weak or not working.
Clogged filters.

 

Does the starter spin the engine as fast as normal when trying to start?

 

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^^^^^^^^^^
If the batteries and starter are strong, check valves would be next.

 

My truck would start normal if I drove it every day. But after two days of sitting, the truck wouldn’t start. It was the check valve.

 

Here is a simple thing to try before you start replacing things that don't need replaced.

One by one, pull out, clean and replace the fuses in the fuse box. If one of them is corroded, it is possibly not supplying enough voltage to the fuel shut off switch.

I know it sounds weird, but I know of at least two cases of friends of mine with older Detroit powered trucks that this has worked.

 

Truth in the electrical connection theory.
Old fuses, corroded contacts or wires.
Have had problems because of that.

 

My Cat didn’t like to start. Replaced the filters and things are fine. Filters are an easy place to start.

There was a bird feather in my fuel filter. No idea how.