2005 150 4 stroke sluggish cranking

[bigfishbobby]

Hi guys, hoping you can help me out. I have a 2005 yamaha 4 stroke that I have been experiencing some problems with. I have changed my battery and I am 100% sure it is good and it meets factory specs for cca and reserve capacity.

The motor at times will not turn over when I turn the key. After turning the key a couple times, it will turn over slow (like it has a dead battery but once it begins to turn over it will turn over faster and crank. The motor runs fine once it is cranked up. No smoking, no burning oil, no leaks, no shaking, no stalling, no noises, etc. It will actually pull enough juice to kill my gps trying to turn over. It will do this at any point of the day.

Any ideas of where to start diagnosing my problem? Thanks in advance for any help!

[rodbolt17]

a quick voltage drop test on the positive then negative leads will tell you.
do a forum search on voltage drop.

[bigfishbobby]

Thanks. I didnt even think about the battery switch. I may just change it instead of doing the direct cranking check since they are inexpensive and I have to disconnect anyways. When I was coming in yesterday I noticed my GPS reading 11.9 volts as well while running 3900 rpm. Is it possible the switch wouldnt allow the alternator recharge as well? It fluctuated between 12.2 and 11.8 the whole way in. Forgive me for what are likely rookie questions.

[99yam40]

best to test things before throwing parts at the problem.
Could be battery cables themselves, battery cable connections( either end), start relay contacts, or any other connection in the start system.

The testing tells you where the problem is

[bigfishbobby]

Thanks guys! Is it likely the recharging and starting problems are connected? I am thinking if it is a wiring or connection issue that it would be likely. If not maybe I have two separate issues going on?

[99yam40]

Could be, testing will show where the problems are.

Why are you against testing things?

[bigfishbobby]

I am not against testing things. My boat is an hour and a half away and since I have already admitted to being a rookie at this I just want to be sure I have the best understanding of the complete situation beforehand. For all I know, you could have given me a different piece of advice for attacking the recharging problem.

[rodbolt17]

did ya do that forum search?
pics and diagrams have been posted.
its a stupidly simple test procedure that MOST techs fail at for some reason.

follow the steps and it will confirm or eliminate cables,solidoids switchs and connections.
entire test may take 20 minutes, or less.

or chunk parts at it.

you will find the Yamaha cables a tad on the pricey side.

[madharchod]

OK it seems like you have a cable problem ,to rule out your solenoid ,i would like you to turn the engine either way and start and see which way it cranks and which way it dosent ,the side it dosent its the cable damaged on that side ,and i would be changing to a new pair of cables ,cost only 30.00 .if this dosent happen then i would be checking the solenoid and to do that i would be taking a multimeter and checking the power supply ,sometimes the starter solenoid is stuck and it would do like this , a simple whack with a small hammer should do the job ,or so a service on the starter motor ,thats what i will be doing as if the engine runs after starting its either the power to the starter or the cable for power supply
you dont have to be a rocket scientist to work this out if you so far away from your boat
cheers

[99yam40]

you have to decide who's advice to take on a web forum, so take posts with a grain of salt, so to speak

Some just post BS

[madharchod]

there is always critic to people who have hands on experience and some who are just starting to earn a living out of scamming people to believe they know too much like the apprentice

[bigfishbobby]

I did do the forum search. It shows 7 threads but I dont see the diagrams, etc you spoke of. Can you post a link to it please? I wont be getting to the boat until the weekend at the earliest but it is sitting on a buddy's lift that will take a look at it for me through the week. I really appreciate you guys helping me out.

[bigfishbobby]

Cleaned connections on battery switch and waalaaa! 14 volts on gps so we are charging again and the slow crank and nothing on key turn at times see s to be gone. Thanks for the help guys.