3116 won't turn over after batteries died

MAKC

Member
Oct 23, 2006
519
Windsor Locks, CT / Milford, CT
Boat Info
1997 400 Sedan Bridge
Engines
3116 Caterpillar
Hey all.

I noticed my refrigerator on my '97 400DB wasn't getting cold on the hook, so i went to start the motors and the starboard side wouldn't even turn the motor over. I fired up the port motor (started right away) and then used the emergency start switch to get the starboard motor fired up. It started to turn over for a quick second and then stopped. No matter what i tried, i couldn't get the starboard motor to turn over. I put in 2 brand new batteries (group 31's with 860 MCA) and the motor still wont turn over. The starter sounds like it fully engages, but then nothing. I would compare it to a gas motor being hydro-locked as to what it sounds like. I checked the fluids and everything looks exactly the way it should (no water in the oil) and the motor was running perfectly when i shut it off a few days earlier.

Any ideas on why it wont turn over at all? Is there a pressure relief valve somewhere that would help it turn over? (I'm a diesel newbie, forgive me). Any ideas or assistance would be so appreciated.

Thanks
Mike
 
Mike if that side is really really dead, then it will not turn over even with the emergency start. If you have some time, fire up the generator and charge the batteries.
 
Mike if that side is really really dead, then it will not turn over even with the emergency start. If you have some time, fire up the generator and charge the batteries.
Did that and no luck. Limped to a marina and replaced the batteries this AM. Running shore power to make sure the new batteries were topped off and same thing. Starter engages and then does nothing (engine wont turn over).
 
Did that and no luck. Limped to a marina and replaced the batteries this AM. Running shore power to make sure the new batteries were topped off and same thing. Starter engages and then does nothing (engine wont turn over).

Do you hear the solenoid pop open when you hit the starter switch ?
 
I'm confused...

The engine is turning when the start is pressed? Or its completely locked up /stalled?

If its locked up, I'd stop everything and get CAT onboard and make sure you don't turn a possible minor correctable issue into an major rebuild.
 
I'm confused...

The engine is turning when the start is pressed? Or its completely locked up /stalled?

If its locked up, I'd stop everything and get CAT onboard and make sure you don't turn a possible minor correctable issue into an major rebuild.

it won’t crank after it stalled initially. I knew the batteries were bad and replaced them. Still same issue. I haven’t kept trying because it should be turning over at this point. I definitely don’t want to damage something internally so I figured I’d see if anyone had any ideas. Was running perfectly before the batteries on that bank died.
 
it won’t crank after it stalled initially. I knew the batteries were bad and replaced them. Still same issue. I haven’t kept trying because it should be turning over at this point. I definitely don’t want to damage something internally so I figured I’d see if anyone had any ideas. Was running perfectly before the batteries on that bank died.

Pull the starter and bench test it?They come off pretty easy
 
CAT mechanic says possibly hydro-locked with fuel from a stuck injector? More info to come tomorrow. I'll update the thread. I do appreciate the responses. Thank you!

Not a diesel guy, but learning. You should try to turn the crankshaft with a breaker bar to see if she is truly "hydro locked'. If that is the case, you should be able to pull the glow plugs, then while cranking it should purge the cylinder of fuel, at which point you will know which injector is stuck open.
Other wise, I would do as @Strecker25/Ryan says and bench test the starter.
This is far less intrusive.
 
Not a diesel guy, but learning. You should try to turn the crankshaft with a breaker bar to see if she is truly "hydro locked'. If that is the case, you should be able to pull the glow plugs, then while cranking it should purge the cylinder of fuel, at which point you will know which injector is stuck open.
Other wise, I would do as @Strecker25/Ryan says and bench test the starter.
This is far less intrusive.

tough to do and like you said pretty intrusive on a 3100 series. No glow plugs, and the injector has to be pryed out. Reinstall means reaming the injector cups, new cups installed, and running the overhead on the engine. It’s a specialized process.

The breaker bar option is doable though, even just as a quick test
 
Update:

Pulled the starter and tried to move turn the engine over manually. It wont move (much). Going to remove the injectors and check for fluid in the cylinders. Maybe a broken injector return spring or injector cup? Hoping to find out what liquid has this engine apparently hydro-locked. What a way to learn about diesel engines! lol I'll post what we find.
 
I think you are at the point where you need to get an experienced Cat technician on the boat to help you. If you do what you are planning to do, you will need 2 sets specialized tools. If you remove an injector, you will need a special reamer to re-face the injector cup or to replace the old one. Then, if you get your problem solved, you will need to re-set the overheads (valves and injectors reset) and that takes more expensive and specialized and (gauge blocks, pins and a dial indicator) tooling that you will very likely only use once.

Good luck with it.
 
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Ill second Frank in suggesting your at a point that if you continue to pull the injectors as you've suggested your going to get into some very expensive areas of these engines. You just cant pull/reinstall the injectors like spark plugs.

In order to turn these engines over, I've seen videos of technicians using 6' long breaker bars and all the force they can muster to turn them, so I'm not convinced your hydro locked, just yet. These engines are pretty robust and issues tend to be simple reasons things dont work

Have you pulled tested the starter, and verified its operation? Checked and retorqued the electrical connections to it? These are free and easy and if all is well there then proceeding to more complicated would be warranted.
 
Well i had a Cat mechanic come take the injectors out and sure enough, cylinder 4 was filled with diesel fluid from a stuck/broken injector. We removed the fuel with a small pump and inspected the cylinder and found a piece of the valves had dropped into the cylinder and collided with the injector. This is heartbreaking since there were literally no signs that anything has ever been wrong with the engine. Time to work with Cat and see what my options are for a short block rebuild. I don't believe that these can be rebuilt in the 400DB so engine removal is going to be the first thing to figure out.
 
Well i had a Cat mechanic come take the injectors out and sure enough, cylinder 4 was filled with diesel fluid from a stuck/broken injector. We removed the fuel with a small pump and inspected the cylinder and found a piece of the valves had dropped into the cylinder and collided with the injector. This is heartbreaking since there were literally no signs that anything has ever been wrong with the engine. Time to work with Cat and see what my options are for a short block rebuild. I don't believe that these can be rebuilt in the 400DB so engine removal is going to be the first thing to figure out.

very sorry to hear that. Keep us posted
 
That sucks. Have you pulled the head off to see inside the cylinder? Maybe its "just" a new head and injectors and resetting the head?

Keep us posted on your progress.
 
Get your insurance company involved before you start repairs. If you are covered, they will want to see the damage first hand.

Yes for sure. I had to have the Cat mechanic come out to see what the issue was with the engine not turning over. Thats when we discovered the issue and the cause. We've stopped work for the moment to contact insurance and then see about working with Caterpillar directly. Will update this thread as more details come in.
 

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