smoking belts and blown starter?

[glonek5]

Ok- hoping this group can assist me. 2005 Hunter 38 Yanmar 3JH4E
Last fall on our last sail suddenly smoke came from below. smelled like rubber so I wasn't as concerned. Pulled into out dock and the belt was "slipping?" and major black dust all over. Ok the belt. I had a spare, replaced it and went to start the boat- nothing but a click. I replaced the starter battery just in case nothing. Checked power to the starter etc all good. Our harbor came out and popped in a new starter perfect. All good.
So... start the boater couple of morning ago. All good, idling out and huge squealing noise from below. Very small load on the motor. Went away and the smoke comes up again. I pump out and pull back into out slip. Looked and black powder all over from the belt. New belt...
Well popped on new belt and guess what-- starter appears to be out? Power is to the starter, solenoid is engaging. Couple of my thoughts, what is causing the belt to do this. My guess is something is seizing and the belt continues to go around it. Secondly, how could this affect the starter? Lastly, the water pump and alternator appear to be spinning freely.

 

[KD3PC]

starter solenoid is not releasing or is engaging while the engine is running...check the flywheel for damage or teeth missing. Meter the solenoid to verify the ABSENCE of DC voltage unless the key is on and turned to start..

could be wiring, or it could be a bad starter...happens frequently with the parts quality we see today

 

[glonek5]

The motor ran smoothly the entire time and the last starter all teeth were good. Seems odd that the belt goes first?

 

[CrispyCringle]

There is no connection between the starter and the belts. I cant explain how they fail at the same time. As for the belt, the common issue is a seized or worn out idler pulley, or a miss-aligned pulley. With the belt off, there should be no play or wobble on any of the pulleys. Also, they should spin freely and without any roughness what so ever. Check the pulley alignment visually if you can. The tolerance is very tight on this measurement. And by alignment, I mean all the pulleys are on the same plane- one isnt sticking out to far or to little. Also, all pulleys are parallel- none cocked at an angle. Make sure the belt tension is correct. Could easily be some ham handedness when installing the belt and putting it on way too tight. Lastly, look at the belt while the engine is running.

As for the starter, did you get a rebuilt starter or new. Its fairly common to have a rebuilt unit fail early. Hopefully, under warranty.

 

[glonek5]

The starter is from another boat (borrowed.. long story). Nothing has changed on the engine over the past 7 years , run perfectly and no changes in alternator, load, water pump etc. So odd and I really don't see how the same thing could happen twice - belt burns first and then starter second in less than a year.....? Could the alternator burn out the starter?

 

[CrispyCringle]

Hmm, so are you saying the starter failed at the same time as the belt, or sometime after (days, weeks)?

 

[glonek5]

almost immediately I'm guessing. Motor was on for 15 minutes- started fine. Belt howled, pulled back into slip, changed belt and no starter.

 

[glonek5]

almost immediately I'm guessing. Motor was on for 15 minutes- started fine. Belt howled, pulled back into slip, changed belt and no starter.

Ok update. Last Friday started the motor, just fine, 4 minutes or so warming up my wife hears a huge noise and smoke and shuts off the motor. I am coming back down the dock and smell electrical something burning- my boat. I do not believe now that this is a belt issue. I mistakenly believed that the smoke is from the belt. The belt is not glazed. The smoke I think if from the fried starter. Perhaps starter is staying engaged and running itself into self destruction? Making more sense now.

 

[glonek5]

this was the 3rd time in one year this has happened.

 

[SycloneDriver]

I wonder if the key switch could be sticking in "start" or some how the start circuit is being energized after releasing the key (or the push button)? Generally you can hear the starter continue to run.
Have you noticed what the battery voltage is before and after starting the motor?
How big is the house bank? How old?

 

[CrispyCringle]

Interesting development. Without re-reading this thread, I recall that several starters have been replaced. With this new info, I would agree with SycloneDriver. Must be the switch. My first inclination was bad solenoid. But that is normally replaced with the starter. Has to be the switch at this point. And makes much more sense now. The multiple belt and starter failures was beyond possible.

 

[glonek5]

replaced the starting battery after the first incident. all fully charged on start. I have a feeling it is staying engaged and I'm not hearing that it is..... Someone also mentioned another relay on the back of the motor that controls the starter and they said that may be malfunctioning.

 

[Maine Sail]

replaced the starting battery after the first incident. all fully charged on start. I have a feeling it is staying engaged and I'm not hearing that it is..... Someone also mentioned another relay on the back of the motor that controls the starter and they said that may be malfunctioning.

Probably time to bring in a new technician, one with at least an ABYC certification, as this could result in a fire if you're not properly diagnosing & fixing the issue....

 

[CrispyCringle]

You may have a set up like this. This shows a main battery cut-off, starter switch, and the start control relay.

If the wiring is similar to this, you can remove the heavy gauge Positive from the solenoid (so the starter wont turn) so you can test the operation and see if the solenoid is staying energized. Either by listening for the engagement/disengagement, or volt meter. DO be careful with that loose positive cable tho. Make sure the battery is disconnected/turned off until the cable is secured. Wrap the end in tape and secure it.

 

[glonek5]

they did it the last 2 times.... I'll take the blame though. I was assuming the large squeal and smoke was from the belt. Looked this time and the belt is not glazed. (Really wasn't last time either in hind sight.) I was walking back down the dock back to the boat and smelt electrical burning. It was from my boat. The starter will be pulled this week and they will have it rebuilt and hoping that will tell us what happened.

 

[glonek5]

thanks

 

[JimInPB]

I have seen situations where a starter was not installed with the bendix in perfect alignment with the ring gear or the support bushing behind the bendix. Sometimes that causes the bendix to hang up & not release, which then keeps the starter motor running, even after power to the starter solenoid has been removed. I have had a few cases where I needed to shim the starter to get the bendix to line up properly & move freely.

If the bendix was stuck on, & that kept the starter motor energized, that would put a large load on your battery & your alternator. That large load might be enough to smoke your belt. It would also fry your starter motor if it happened for a long enough period of time.

 

[SycloneDriver]

Jim
FYI
The bendix is the gear on the end of the starter. It has a one-way bearing inside it. This is to prevent the engine from spinning the starter motor but allow the starter motor to spin the engine.
The starter mounted solenoid has two functions: 1st it's attached to a fork that pushes out the bendix to engage the ring gear on the flywheel, 2nd the solenoid has a set of large contacts that close and supply power to starter motor. It happens in this order: 1. power is sent to the solenoid via the starter switch, 2. the solenoid pushes the bendix out to engage the ring gear, 3. the contacts close and power is sent to the starter motor.

 

[JimInPB]

In many systems like that, if the bendix is held out mechanically (bound up some how) then it will hold the contacts closed, supplying power to the starter motor, even after power is removed from the solenoid coil. I do not know if that is how your system is set up or not. It is a common set up on many motors. Even with the one way bearing, the starter motor will still draw a fair amount of current if it continues to run after the engine starts.

 

[CrispyCringle]

Bendix? You guys are showing your age, I think.