Starting Problem w/Yamaha 8HP OB

[deathstare]

I'm new to Sailnet... so first let me say hi to the community here. I just started sailing this year; bought the boat in April and sailed it off of Beaufort NC pretty much every weekend this past summer, the wife and kids joining me in the latter half (once my wife was satisfied I wouldn't sink it or otherwise embarass us). So far it's been a great experience.

Got a question on what seems like a backwards starting problem (bear with me.. I'll explain) with the Yamaha OB on my S2 7.3 that spang up at the end of the summer when I wasn't going out to the boat every week.

Here's the sequence, after the boat has sat for about 2 weeks or more (full disclosure: I keep the boat on a mooring):
1) 1st turn of the key... nada seems like a dead battery
- checked battery, has 10.5V, lights/other electronics work fine
2) wait a few minutes... turn again... a click
3) wait a few minutes more... turn again... fast clicking (like a car whose battery is dying)
4) wait a few minutes more... turn again... engine turns over once, then nothing
5) repeat ad nauseum (engine seems to turn over a few more times more each iteration, if you don't wait a few minutes in between attempts you get nothing)
6) after 30-40min and multiple key turns (and a lot of swearing ) ... engine cranks enough times to start
7) after it's started, you can shut it off and restart np

I thought the battery leads might not be in good contact (volts, but can't pass the amps) but I've repeated the above without touching the battery or leads (eg. to measure voltage) and it is exactly the same.

I'm thinking either the key switch is shot (bad contact 1st, 2nd, ... Nth turn) or the starter is bad (although I've never seen a bad starter behave like this). Before I start replacing stuff, has anyone ever see this before and have an alternative theory?

[TheFrog]

Time to check your battery. 10.5 volts is a dead battery, fully charged you should have ~13+ volts (depending on battery cell type).

Check your fluid levels in the battery. Also, how are you charging the battery? Do you have solar cells? It is possible that you have enough self-discharge and parasitic loads in the 2 weeks between sailing that you are draining whatever you had the battery charged up to out (presuming you have no maintenance charge system).

[philsboat]

When checking the battery voltage put the probes on the lead posts of the battery for the first reading then on the cable ends where they are fastened to the battery for a second reading.If the readings differ it could be a high resistance (bad) connection on one of the cables.Do the same at the starter (positive connection ) and the engine ground.

Phil

[Vasco]

If you're on a mooring how are you charging your battery? Does that small Yamaha have an alternator? 10.5v your battery is dead.

[timebandit]

Most electric start outboards have a 20-25 amp charging system.

10.5 volts is a dead battery. It seems that you are charging just fine but the battery won't hold a charge or you are leaving something on that is running it down.

How old is the battery?

Maybe it is just time for a new battey.

[deathstare]

Thanks for the replies.

re. Battery age: don't know, but the boat sat for over a year in a boatyard (on blocks, no charging) before I bought it and, with the exception of a gummed-up carburetor that had to get cleaned up, it cranked and started no problem

re. charging: none - this summer I was on it pretty much every weekend, it wasn't until August/September when my visits became less frequent that this issue came up... and the 1st time I noticed it, it had only been 2 weeks since my previous trip. w/battery isolated on the switch, figured it should hold a charge at least that long. I have a portable jumper battery I can bring with me now that the visits are more like a month apart.

no one's commented on the sequence of events though... battery strength doesn't seem to be a problem after 30min of messing around with it. my experience (cars and other terrestrial vehicles) has been that if the 1st turn of the key produces nothing... the 10th turn isn't likely to produce anything more.

I'm heading down this w/e to the boat (1st time since Oct. 4th) and I'll have my jumper with me so I can test the battery vs. downstream issues as the root cause.

[deathstare]

sorry... on the charging I really should have said "only when the engine's running", the yamaha does indeed have an alternator

[timebandit]

If the battery is only 10.5 volts there is not much you can loose to the motor.

Maybe it is the oil starting to circulate that allows the motor to turn over.

The engine might be coming up on the compression stroke when you first try to start it and then once over it will crank.

You didnt say if it was a 2 or 4 stroke or it's size.

[deathstare]

Finally got out to the boat Friday after Thanksgiving.

Brought a battery charger with me (one of the little hand-held units).

Without the charger: the battery was holding about 10V but wouldn't crank the motor (only tried it once).

With it: motor cranked and started no problem.

Guess I'll be battery shopping, or investigating solar chargers to keep the battery from loosing as much charge.

[timebandit]

"Check your fluid levels in the battery"

Have you?

A dry battery won't hold a charge, batteries need water (distilled).