Starter or Battery issue

Boat had been running great. Started to have sluggish starts over the course of a couple weeks. However, once boat was up and running, could easily start when needed. Boat sat for another 2 weeks, and not I turn the key and the starter clicks into the flywheel, but doesn't turn.

Charged both batteries (which were low) and clean corrosion that had built up. Tried to start last night and same ordeal. Started clicks into flywheel but doesn't turn.

Took started off. Starter felt a little warm.. Took battery cables and hooked starter to battery and it turned over fine.

Little confused.

If the starter is turning with the direct connection to the battery, started can't be bad can it? I am wondering if I should try new battery cables, or is there a possibility that the started can turn when it doesn't have the weight of the flywheel against it?

Re: Starter or Battery issue

could be corroded cables. they make look fine on the outside, but could be corroding on the inside. are the cables ever hot?
could also be bad connections. pay attention to ground connections.

good luck.

Re: Starter or Battery issue

cables sometimes I would say can give some heat. I am going to try to replace the lugs and on the battery cables and see if that helps. will also check grounds too.. can the starter be bad you think? i am just wondering if turning with the weight of the flywheel and turning with nothing really show whether or not the starter could be bad..

also any idea if it may be an ignition switch?

Re: Starter or Battery issue

Have you tried to check the voltage drop at battery and other places on the cables when starter is engaged?
That will tell you if there is a bad battery,connection , locked up motor, or bad starter.
Sounds to me like it is a bad battery, just my opinion

Re: Starter or Battery issue

put in new batteries last night and still same issue. one thing I do notice is that all electronics will cut out when key is engaged...

Re: Starter or Battery issue

That sounds like you are dropping voltage too low to keep things powered up. Could be a connection or too much load. test to see what is going on

Re: Starter or Battery issue

Sounds like a bad battery cable or bad connection. I just dealt with a bad starter on a friends boat and his instruments wouldn't go out when you tried to start the motor. So you must be having voltage drop which is a result of a bad wire or connection.

Re: Starter or Battery issue

do a forum search.
key words, voltage drop test.
one of the posters here was at MMI and posted the procedure complete with pictures.
works well.