Cummins 6CTA starter/solenoid - can I replace just the solenoid

[ZZ13]

Not sure if I have a starter or solenoid problem. Solenoid is bolted to the started on my 6CTA. Since I bought the boat the port starting has been an issue. First time it happened the mechanic was there and we got the "click" when we pushed the start switch at the helm, but the starter didn't turn. He bypassed the solenoid with a screwdriver and spun the starter and then it started right up. Started fine for me the next outing. But it didn't start again today and after three tries at spinning the starter the same way, it still doesn't start. So if its the solenoid, can that just be taken off the starter and replaced, or are these a paired item only sold together? Also, I am welcome to any troubleshooting suggestions.

FYI, the starter is a remanufactured starter installed on 4/22/2013 - so if there is a year warranty looks like I missed out (again).

 

[SR400DB]

I had the same issue, it turned out to be the rocker switch at the helm on my boat. I diagnosed by switching the units at the helm and the problem shifted engines. May be worth a shot

 

[ZZ13]

That would be so wonderful and such an easy fix. I happen to have just purchased a bunch of spare switches. However, when I press the rocker switch I can hear the solenoid click. So unless that click is actually the rocker switch itself, I think it may not be that easy for me.

 

[fwebster]

I don't know the answer to this on a Cummins powered 400DB, but the Cat powered boats have a relay somewhere near the engine that triggers the actual starter solenoid. The amp draw for the starter solenoid is so great that a relay is usually positioned near the engine to save running a large gauge wire from the bridge to the engine. It works just like the slave solenoid on a Mercruiser. If your mechanic was able to jump the solenoid on the starter with a screw driver, my guess is that the problem is in the relay instead of the solenoid on the starter.

Find it and put a volt meter across the secondary terminals and then hit the starter switch. "0" volts means the problem is the relay or further up stream toward the switch..........12.6 v or higher means the problem is at the starter.

 

[trit21]

Not sure about the 6c series but on my 6b, the relay that Frank is talking about is not he same side of the engine as the starter, basically under the starter near the oil pan. There are actually 3 relays there so make sure you have the correct one. The other relays are for the air heaters and they all look the same. The 2 that are wired together are for the air heaters and the one about 3-4 inches away is the starter relay. But again, this is for a 6b and not the 6c but I would be there are similar.

 

[Woody]

Don't forget to check wires/connections. IMHO...of all the starters, solenoids, and switches ever replaced because of the dreaded 'click' the majority weren't necessary.

 

[ZZ13]

After consulting with sbmar for a while and going through a debug process it turns out the starter gear wasn't pushing forward to engage with the engine gear. Tapping the starter with the hammer freed it up and it started up the engine just fine after that. Now I gotta decide is this just from lack of use (meaning use that boat more ZZ13) or is it a gunked up 14month old starter from moisture intrusion or whatever, or is it just pot luck reliability you get with remanufactured stuff. I think I'll just buy a brand new starter from sbmar and take this one off and try to clean it up and lube it up and keep it as a spare.

In the meantime, I got the hammer on the boat.

 

[Jaws]

Bill,

I had a somewhat similar issue on my 6CTA back in 2008. It was diagnosed as a bad starter so it was replaced. Well, same story as yours, it failed again the next year and was then diagnosed as a bad relay so I replaced that. (I used the screwdriver to start the motor a few times that year but usually only after we took on fuel, so a hot motor.)

It's been fine since 2009 but I've always been suspicious that the neutral switch on the shift lever was malfunctioning so check that too.

James

 

[fwebster]

Don't rely on the hammer.

The bendix on the starter is dragging and while it may be engaging enough to crank the engine, it could also be partially engaging. The gear on the starter meshes with the ring gear on the flywheel and a partially meshing gear set wears the gear teeth very quickly. The starter gear is easy to get to for replacement.......the one on the engine requires removing the transmission......not so easy and certainly not cheap.

 

[1956olds]

You could get a cummins quickserve account for free ,they have a troubleshooting guide for the starting systems.You will need the engine numbers to register but it was very informative about testing the starter ignition switch and magnetic switch(relay).

 

[ZZ13]

Thanks Frank. I agree. We are pulling the starter and giving it and the flywheel gears a full inspection before we do anything.

 

[sdarc]

Do these starters need to be shimmed for correct clearance? I know you do this in the auto world (Chevy) just curious if it is done on these boats?

 

[ZZ13]

I am working on removing the starter. Outside and bottom bolt were easy. Had to disconnect the turbo oil drain at the engine for the bottom bolt to make room for the socket. So now I am on to the inside bolt. A long extension isn't working because I have to come at a slight angle to clear the starter body. So I am thinking the following:

1. Remove all cables connected to starter and move them out of the way
2. Remove cables from mag switch mounted under starter and pull it out of the way (it runs right on top of the bolt head)
3. Remove rubber elbow hose at aft end of heat exchanger.
4. Remove temp/pressure gauge mount and move it out of the way.

Seems that should give me plenty of room to get my hands, eyes and socket in from the top.

Any of you done this and does my approach make sense?

 

[Jaws]

Which motor? The difficult one? Mine was port side, V-drive.

It was six years ago but I can't remember having too much difficulty (two of us working) and we used a similar approach. Toughest part was holding that heavy starter for the re-installation.

Good luck.

 

[ZZ13]

Which motor? The difficult one? Mine was port side, V-drive.

It was six years ago but I can't remember having too much difficulty (two of us working) and we used a similar approach. Toughest part was holding that heavy starter for the re-installation.

Good luck.

The easy one - port.