When a motorcycle photo became a boat

[peterbaron]

I was just settling in for another frustrating evening of troubleshooting a boat problem ...

What is the problem...?

....besides that, my time to visit the cemetery has not come yet... and many more miles are ahead of me...

[Lunchbag]

I was just settling in for another frustrating evening of troubleshooting a boat problem ...

What is the problem...?

The motor won't start or turn over when I turn the key.  It only makes a click.  However, when I short the terminals of the starter relay with a tool, the motor turns over and starts right up.

Coincidentally, I had identical symptoms on my '89 F150 just last week.  I put in a new starter solenoid and that fixed it.  But after I replaced the starter relay in the Yamaha F115, it did not fix it.  It had the exact same behavior as with the old relay.

I bench tested the old relay and it appeared good.  However that was not under load, so I can't really confirm it is good.  But since the new and old relays act identically, I think they are not likely the issue.

I cleaned up all wire terminals attached to the starter relay, but it didn't change anything.  The battery is new and I cleaned those wire terminals also, and like I said it starts up strong when I short the relay.

The only thing I can imagine is that somehow my 12V signal to the relay coil is weak and unable to close the relay properly to handle high starting current.  Just enough to make a click, but not to start.  Is that possible?

I think next I'll take a spare 12V battery and connect it directly to the small (coil) relay wires.  See if it starts up, and perhaps measure the voltage under load and no-load.

Then compare voltage under load and no-load while attempting a start from the console.  If voltage is low or voltage drop is severe, somehow trace the wires to find out where the drop occurs and repair it?  If all else fails, rewire with a good 12V supply?

Please let me know if you have other ideas...

[peterbaron]

The best for diags is if you could provide your F115 starting system electrical diagram, but I assume it looks like this one below with 4-prong relay.... and I make my diags based on THIS diagram below:




Your thinking is correct, and it sounds like a voltage drop during starting

1. you: 
The motor won't start or turn over when I turn the key.  It only makes a click.  However, when I short the terminals of the starter relay with a tool, the motor turns over and starts right up
me:
I assume that you removed your relay and bridged SWITCH terminals 1 & 2 of the start relay when the ignition is ON and your Yamaha runs  = black, green and red circuits  / LEFT side of this starter relay diagram have no isue, as well as components such as battery and starter/solenoid- integrated unit
..... but ignition switch "START" circuit needs to be verified

2. you:
I bench tested the old relay and it appeared good.  However that was not under load, so I can't really confirm it is good.  But since the new and old relays act identically, I think they are not likely the issue.
me:
this is correct, also the relay coil resistance between terminals 3 & 5 should be around 70 Ohms - automotive standard, but may very from 50 - 150 Ohms

You most likely have a problem on the coil circuit side like wires, contact points/ RIGHT side of this diagram - either pink/B+ or black/NEG/ground controled by the ECM

MARINE may have a total different set up, so my diagram is just an electrical troubleshooting idea.

Here is AI
https://www.google.com/search?q=f115+sta...AEYASABKAE

https://www.google.com/search?q=f115+mot...s-wiz-serp

[Lunchbag]

You most likely have a problem on the coil circuit side like wires, contact points/ RIGHT side of this diagram - either pink/B+ or black/NEG/ground controled by the ECM

Yup.  I made a little progress this morning.  I'm wondering if a moderator/admin would like to move these last three posts into another thread so as not to distract from the photo challenge?  Or I could switch to PM w/ peterbaron or create a new thread...

[peterbaron]

Yes, I agree


Posts no: 5392 /1st paragraph, 5397, 5401, 5402, 5403, 5404 should be moved by the admin/moderators to a new thread with a new title, authored by Lunchbag.

[Gone in 60]

I can't look.... I'm trying to fix my own electrical problems right now.
But boats?... yeah, wouldn't own one... love to borrow them though.

I mentioned watching some digitized home movies my friend shot back in 1990. In one of them, we're all on his Dad's Bayliner bombing around the Newport coast, each of us taking turns being pulled in a big inflatable saucer. (Huh... just realized that was before Super Duties and Chevy HDs existed... he was pulling that dual axle monster with an El Camino...)

I remember his Dad's decree... "You can all ride in the boat and have a great time. But when we get back home, you all have to help clean it."

[peterbaron]

To Cormanus 

Gone, we carry out all repairs and diagnostics using the knowledge of forum members

[Cormanus]

I recall on the old forum us moderators would feel a need to shut down or delete conversations that got too far away from the CB1100 or motorcycling. I'm pleased you asked me to move this conversation as it saved my already troubled mind from having to figure out what to do with it all by myself.

Perhaps you could humour us moderators by throwing in the odd reference to a motorcycle or motorcyling? For example, someone might say something like, "Unlike my old 2-stroke Suzuki T250, the electrics in this engine ..." I'm sure you get the idea. If not, ask the Ferret; he's a past master of this. In that way, forum members will not only have the opportunity to read all about peterbaron (and maybe others) helping Lunchbag to fix his boat, but also watch their contortions trying to make the exercise relevant to a motorcycling forum.

[Lunchbag]

Yes, there is the interminable debate about thread drift, and what to do about it.  I hope in this case the creation of a new thread in order to not distract from the photo challenge is agreeable to most readers.  Thank you, Cormanus!

Anyway, I made some progress yesterday.  First I used a spare 12V battery to directly activate the coil of the starter relay, and it started right up.  That put my mind at ease regarding the relay and everything downstream.

I also did continuity checks on the wire that activates the relay, from the relay to the 10-pin connector of the motor wire harness.  All good.  Then I did continuity checks on the main wire bundle from the motor to the console.  It was also good.

Next, I did some tests with the key switch and kill switch.  I referenced a diagram I found online which I hope is accurate.  The off position and the kill switch worked as expected.  The run and start positions did not.  When I checked for continuity between red and yellow, and between red and brown (diagram below) with the switch in on and start, I didn't get anywhere near zero ohms.  It was ~10k.

I can't say for sure, but maybe that resistance is enough to weaken the signal to the relay coil.  So it will click, but not really close properly.  It does run though, once started.

I removed the key switch and brought it inside last night, and went to bed.  My plan for this morning is to put some contact cleaner in the key hole and work it around, and retest it.  If that doesn't work, maybe I can get it apart.  I don't think so.  If that fails, look for a new one.

Sorry I'm not going to be able to get motorcycles into the conversation...if this was a Yamaha problem (and the F115 has given plenty of problems) I could talk about how much more reliable my Yamaha dirt bikes were than this.  But I think the Yamaha is fine in this case.  Let me know if anyone has a better idea about how to explain the 10k ohms and what to do about it...

   

[Lunchbag]

Good news.  I dripped a lot of contact cleaner into the key hole and worked the key back and forth.  It took a little time but I got the start position to zero ohms.  Strangely, I did not get the zero ohm reading I was expecting in the run position, but running hasn't been a problem, so I felt it was good enough.

Reinstalled the key switch and started and ran it a few times.  It's working, at least for now.  Good enough for the long weekend and family gathering I think.

I may order a new switch anyway.  The contact fluid that dripped out of the switch was very brown, and I expect there is a bit of rust inside.

The thing about electrical problems is, I always seem to start in the wrong place, and I only find the problem after going over the whole thing.    Oh well, I guess the fact that a few other connections have been cleaned up won't hurt anything.

And did I mention...motorcycles