Our 1999 40" SeaRay Sundancer with...

[Smokey]

Our 1999 40" SeaRay Sundancer with Caterpillar diesels has an intermitted starting issues with both engines at times.  We think we may have narrowed it down to the starters, but interested if anyone has any advise or has had the same issue.  When you go to start, the engines are not engaging sometimes until after 10-20 tries with the engine switch on the dash. We have replaced selenoids, transmission switches, and all equipment is kept in very good condition.  Every time we get someone to look at it, both engines start fine, no issues.  When we left to put the boat in stroage, one engine started on the first try, the other engine took at least 20 tries to start. The warning sound goes off, just no ignition.  Any ideas or thoughts would be very helpful.

[wingless]

Trace out the electrical path for the starter.

Use a voltmeter to measure the voltage on the starter path, relative to ground. That method will permit identification of the problem.

It could be a bad part, bad connection or bad wiring, but the problem needs to be identified.

[fwebster]

The Cat electrical system has a starting relay in the electrical box on the engine that must close for power to get to the fuel shut off solenoidand the engine starter. It is a small black Bosch relay .....$16 at ypur local auto parts store. When you move the starter switch to on (not start; just to on) do you hear a loud click which is the fuel relay opening, if you do, then the problem is down stream of the Bosch relay. If you do not hear the loud click, then the small Bosch relay is very likely the culprit.

Caterpillar starters are very robust and it is very unlikely t hat both would fail at the same time, but it is a boat and they sometimes do wierd things. A Bosch relay faailure is usually not an intermittant failure, so this may well be a bad starter.

[fwebster]

As an after-thought, you should also check the neutral safety switch the next time it fails to crank. Find it and check the continuety or just wiggle the shifter as you hold down the start switch.

[Smokey]

Thanks to all that replied. just wanted to let you know we have replaced both nuetral safety switches this Summer, we have put voltage meter to both starters with no real resolution or definite issue noted, and both starting relays have been replaced several times, as this is, in fact, a very cheap part, so my husband always keeps two on hand. As you can see, this has been a very frustrating issue!

[Captain_Rick1]

If you are using a certified Cat maintenance facility and you have indeed done all that is described, I would be looking for a bad ground on the engine BUS. Very frustrating to isolate but that is my bet on the route cause.

[SMT]

I have Cat Diesels and I have had exactly the same problem. To see if this is it when your ignition is on and you push the start switch without starting the engine you should hear a click on the engine. (have someone near the engine if you cannot hear it from the bridge). If you hear the click you engine will start, if you do not it will not. It is the fuel solenoid on the engine. Contrary to popular belief they do not just die they work sometimes intermittently before they die. There is a red reset button on the box (on the engine) sometimes resetting it will start the engine. When the solenoid fails totally you will not be able to start the engine. There are two wires on the solenoidon the manual engine, the electronic version will have three check to see if they are tight and not corroded that could be the problem too.