Charging Problems 175HP Mercury Optimax

[sydney south]

Hi all,

My 2007 175hp Mercury Optimax stopped charging yesterday. If ever I had a better lesson, as why I have two good batteries, that was It. I was able to flick from one battery to the other all day, still have a good day out and not require any assistance to get home. I doubt that I would have even made it home if I have one battery. As I did not notice the non charging until I was down to 11 volts on battery No1.

Now the problem.

Before I open the cowl, and start scratching around for problems. Is there anything that you all may offer as to where to start looking? Such as fuses, circuit Breakers, belts, leads etc?

Thanks in advance.

Sydney South

[a boat]

Hi, before you go "scratching around" on that expensive and complicated engine of yours I would get a genuine service manual if you wanted to do it yourself. It could be something very simple(no fuse for battery charging), but plenty of connections and wiring or complicated and expensive like a faulty alternator.

There are tests that can be done to diagonise why the engine is not charging and I do hope you do not have wing nuts on the batteries.

Cheers,

Huey.

[sydney south]

Hi, before you go "scratching around" on that expensive and complicated engine of yours I would get a genuine service manual if you wanted to do it yourself. It could be something very simple(no fuse for battery charging), but plenty of connections and wiring or complicated and expensive like a faulty alternator.

There are tests that can be done to diagonise why the engine is not charging and I do hope you do not have wing nuts on the batteries.

Cheers,

Huey.

Thanks Huey,

Just as I am thinking. plus I would much rather use the boat than work on it.

Sorry I did not mention. The motor and boat are a 2007 model, but I purchased the boat in 2011 and are the first registered owner and I am under the belief that the 5 years warranty is from the date of purchase.

I will call the dealer in the morning and get some information.

As to the wing nuts. I will have a look and see if they are on the terminals, as nothing has changed from when I purchased the boat. But please advise why the wing nuts are not recommended?

[a boat]

Hi, wing nuts have been a big no since bad old carby days when they would fry rectifiers. With any modern engine I sure hope you do not have wing nuts that will work themselves loose and will cause a lot of things from damaged ECUs to things like you are seeing and IF it has wing nuts the dealer should be shot and Mercury will most likely not warrant any damaged caused by these.

If you have done the servicing by the book you get a 3 + 2 year warranty from Mercury but the services will need to be done and registered with Mercury.

Cheers,

Huey.

[mr475]

I had a problem a couple of years ago in that the charge when the engine was running was down to about 12.5 to 13 volts instead of the usual 14.2volts. In addition, sometimes the electrics would go on holiday and I could not restart the engine when time to up anchor to go home. Fotunately, pulling various leads got the engine started so I got home. I thought I had the dreaded "intermittent" problem. But, starting with the easy stuff first, I undid the cables that went to the earth point on the stern near the isolator switch. They seemed to have a little oxidation on all of them, so I cleaned them with a wire brush and put them back. All problems solved. No more loss of electricity and the recharging was back to 14.2volts as usual. And no money spent.

Just a thought. My boat is a 2000 model Quintrex but the principle may still apply to other boats.

[Beaver]

Hi, wing nuts have been a big no since bad old carby days when they would fry rectifiers. With any modern engine I sure hope you do not have wing nuts that will work themselves loose and will cause a lot of things from damaged ECUs to things like you are seeing and IF it has wing nuts the dealer should be shot and Mercury will most likely not warrant any damaged caused by these.

If you have done the servicing by the book you get a 3 + 2 year warranty from Mercury but the services will need to be done and registered with Mercury.

Cheers,

Huey.

What do you reccomend to use instead of wingnuts to connect leads to terminals?

[a boat]

Hi, depends if you have posts, terminals or bolts, but on terminals and posts you should use nylock nuts or at least stat washers and that way, especially with the nylock nuts you need to do up with a spanner and they will not vibrate loose. I hope you do not have wing nuts and if so and the engine has been fitted or serviced by someone then they should of known better. I would say 90% of boats rigged or service elsewhere that come thru here have wing nuts and as I said earlier it is a big mistake to have them, no matter the brand of outboard or what technology it is.

Cheers,

Huey.

[Beaver]

Hi, depends if you have posts, terminals or bolts, but on terminals and posts you should use nylock nuts or at least stat washers and that way, especially with the nylock nuts you need to do up with a spanner and they will not vibrate loose. I hope you do not have wing nuts and if so and the engine has been fitted or serviced by someone then they should of known better. I would say 90% of boats rigged or service elsewhere that come thru here have wing nuts and as I said earlier it is a big mistake to have them, no matter the brand of outboard or what technology it is.

Cheers,

Huey.

Thanks for the info Huey. Ive got a F100 yamaha 04 model, it's always had those brass wingnut connectors as far as I remember after buying it second hand. I have always tried to ensure they stay tight and check them regularly. The mechanic has never said anything to me about them. I might go and try find myself some of those nylock nuts you reccomend and switch them over just to be safe. cheers

[a boat]

Hi, yes most definitely I would get rid of those wing nuts and find another "mechanic" too if they have serviced the engine and not changed them.

Cheers,

Huey.

[sydney south]

Just an update.

Returned the boat to my dealer and it was diagnosed that the alternator had gone to God.

All being fixed under Warranty.

Thanks all, for your posts and thanks Huey for you input.