CAT 3116 Start/Stop panel question

[FBoykin]

The CAT 3116 diesels on my Grand Banks 42C do not use keys to start (or stop) them. Just push buttons. The guys changing the water pump impellers want to "bump" the diesels so the pump keyways are pointing straight up so they are less likely to drop a key. My diesels start as soon as the Start buttons are pushed so they are suggesting that it's OK to keep the Stop button depressed while they "bump" the Start button until the keyway is up.

I'm not sure this is okay to do - seems weird to push both Stop and Start buttons at the same time. And I have no idea if it's hurting anything. But I don't how else to do it except to get a long socket wrench and try to turn the crankshaft pully by hand.

I've attached a photo of the Start/Stop panel. Advice appreciated!

 

[cks]

Bumping is an ever so quick pushing of the start button. It shouldn’t start.

To test if true, before dismantling the pump try bumping it and see if it repeats as anticipated.

 

[tiltrider1]

Stop button electrically operates a fuel shut off solenoid. Pushing this button will keep your engine from starting when you push the start button.

 

[STB]

Don't hold me to this, but by memory, on that engine, it should be fine.

As I remember it, that solenoid rests forward pressing a shutdown in the pump and is energized pulling it back any time the engine is running. So, depressing the shutdown button actually interrupts the ignition circuit. It can't burn it out.

My memory is that solenoid uses two coils, a pull and a hold. And that the pulls is high current but can only run for a short duration. The hold is low current and takes over for the long haul.

On my Perkins 6.354 it is different. The stop button energizes the pull coil to shutdown the engine. Hold it too long and it'll burn it out as it is designed to be intermittent. I think the Perkins originals are better about that, but they were long ago replaced with generics with only the pull coil wired. So, when someone holds them in for too long they burn. The better idea is to pull up the mechanical shutoff on the pump by hand. But, that is on my engine, not yours.

I prefer to bump my engine with a long handle ratchet on the main pulley nut, i.e. bar it over, exactly as much as needed.

Regardless, I think you are fine, but do collect more opinions.

 

[Comodave]

I don’t have Cats, but on mine it works just fine to hold the stop button and push the start to bump the engine.

 

[Yahoo 1]

Similar boat (but mine is a MY) with twin Caterpillar 3116 as well.

First, push Stop and keep pushing,
Push once on Start while still keeping pushing on Stop,
Release Start,
Then release Stop.

Hopefully my English was understandable.

Since I have been asked by Menzies to prove what I post, please find attached pics of my panel as well, and my engines’ specification.

 

[Steve1.0]

Are the pumps belt driven? Loosen the adjuster, turn the pump by hand and re-tighten. My 3208' are "belted"

 

[FBoykin]

Thanks all for your comments. It sounds like it's okay to do this - press and hold Stop button while bumping the Start button. The Stop button works the fuel solenoid and the Start works the starter, so the diesel just turns over.