Tohatsu 30 - wouldn't start?

[citygent111]

Last time we took the boat out there was quite a swell, and after being anchored for about 30 minutes, I couldn't restart the engine using the key.

It did start with the manual pull cord though (key has to be in the ignition) - can anyone suggest why that might be?

Thanks!

[Limecc]

Originally Posted by citygent111

Last time we took the boat out there was quite a swell, and after being anchored for about 30 minutes, I couldn't restart the engine using the key.

It did start with the manual pull cord though (key has to be in the ignition) - can anyone suggest why that might be?

Thanks!

Do you mean it wouldn't turn over by key, or it turned over by key and wouldn't fire?

[citygent111]

Hi Limecc, when I turned the key, there was nothing.

Usually, the engine makes a high pitched beep and fires up, but it did nothing as though the battery was dead.

To start manual, the key still had to be in the ignition then give the rope thing a pull and it started straight away.

[spartacus]

We probably need a little bit more information.

I assume this a 4-stroke Tohatsu 30hp?

I've been caught out with start-in gear protection before, but that's an obvious one. If you think it's electric related regards the loom, then obvious thing is to double-check the bullet-connectors which can oxidise, because Tohatsu (in fact all outboard manufacturers) don't used tinned wiring.

Also check the battery connection to the starter motor. Remove, lightly sand and reconnect.

Just had a thought the start-in gear protection on the remote can fail. I've replaced the little micro-switch on my own outboard throttle before.

[citygent111]

Hi Spartacus,

yes 4 stroke. I forgot to mention, when I got it back on land, it wouldnt start with the key when i wanted to flush the engine, so had to pull start it again. Took it for a check up the following day at the service place, and it stated first time with the key for them, every day over an entire week!

They took the remote unit apart, checked the wiring - nothing wrong.

I was really just wondering if anyone had experienced anything like it before - could it be the result of the engine getting a bit knocked about by the swell/ waves?

It was a bit scary to be honest, but the boat held up well so that helped!

[jeffstevens763@g]

Dirty contacts on the ignition switch?

[Old seahorse]

Hi City gent. My last boat had a Mariner 30 efi ( 2008, 3 cylinder, 4 stroke ) That engine was made by Tohatsu , so may be the same
(others here will know, for sure).
I had similar non starting issue, which with help of a mechanic friend, was traced to being starter solenoid failure.
I managed to source a solenoid, and replace it myself, with some guidance.Sorry, but I can’t remember part number or price, but it wasn’t expensive. It was a bit fiddly to change, but doable with limited skills. Hope that helps

[Poly]

Originally Posted by Old seahorse

Hi City gent. My last boat had a Mariner 30 efi ( 2008, 3 cylinder, 4 stroke ) That engine was made by Tohatsu , so may be the same
(others here will know, for sure).

Im 99% sure they are the same engine

could it be the result of the engine getting a bit knocked about by the swell/ waves?

Clearly you want to check all the possible connections - so the battery + / - and the isolator switch on the +. Do you have any instruments wired to the battery?

Couldn't be something as silly as the isolator having been knocked?

In my car ownership experience if you turn the key and get nothing but have a good battery its either a dodgy/loose battery cable connection or the starter solenoid and the latter can be intermittent. I had a corsa that lasted a year where about once a month it would die like this - a hard dunk on the starter was enough to revive it... on a boat I'd suggest you want something more reliable than keeping a pole under the drivers seat for whacking duties!

[citygent111]

Had a good look around this morning with multimeter in hand. Battery has 12.6v with nothing switched on.

I've tried to get readings from behind the switch panel (there is no isolator switch), and there seems to be an issue back there.

I was only seeing around 10.5v at the back of the switch for nav lights and radio, but when I turn on the nav lights they don't come on at all. and when I turn on the radio, the voltage at the rear of the switches drops to 0.00v.

Now I am FAR from an electrician (!) but does that sound as though the battery needs charging?

Engine starts fine though but I understand the Tohatsu MFS30C is batteryless !

I'm now more bothered about the nav lights not working than I am about the engine!!

[jeffstevens763@g]

https://images.app.goo.gl/epXznhD1ZXgX2CdY6


12.6 volt and above battery charged

[Jon Tallis]

Originally Posted by citygent111

Had a good look around this morning with multimeter in hand. Battery has 12.6v with nothing switched on.



I've tried to get readings from behind the switch panel (there is no isolator switch), and there seems to be an issue back there.



I was only seeing around 10.5v at the back of the switch for nav lights and radio, but when I turn on the nav lights they don't come on at all. and when I turn on the radio, the voltage at the rear of the switches drops to 0.00v.



Now I am FAR from an electrician (!) but does that sound as though the battery needs charging?



Engine starts fine though but I understand the Tohatsu MFS30C is batteryless !



I'm now more bothered about the nav lights not working than I am about the engine!!

That sounds to me like either a very high resistance connection somewhere or a near-dead battery. Probably the former.
Repeat the test and see if the battery volts drop to zero when you switch on, if they do your battery is either near-flat or goosed. If the battery volts stay around 12 and the voltage to your consumers drops (you'll need 2 meters to check this categorically) then you have a very poor connection or a near-broken wire somewhere. You'll have to trace the voltages back through the system to find the issue. Good luck & keep us posted

[paintman]

Remove and fully charge the battery. Simple stuff first.
Check and clean all connections.

Be aware that digital multimeters can give misleading readings.
Fuel pump on my car appeared to have died but connecting direct to a battery showed it to be fine.
Multimeter showed battery voltage at the pump to loom connector live feed.
Bit of headscratching later I connected a test bulb to the loom live feed. Nothing, not even a glow.
Working back along the wire by pushing a pin through the wire sheath until the bulb lit revealed a partial break caused by corrosion in the wire just back from the connector.
Couple of strands were all that was left.
Enough for the meter to show battery voltage but not enough to pass the current necessary

[citygent111]

Lovely, thanks chaps - a good excuse to spend Sunday messing about with boats again!

[Poly]

Originally Posted by citygent111

Lovely, thanks chaps - a good excuse to spend Sunday messing about with boats again!

Just rewire it all with tinned cable and new connectors... its easier than finding the dodgy wire and what you'll end up doing anyway!

[citygent111]

Originally Posted by Poly

Just rewire it all with tinned cable and new connectors... its easier than finding the dodgy wire and what you'll end up doing anyway!

Well, it's funny you should say that Poly...!

Sunday morning consisted of me removing the main switch panel, then working my way from the battery to the switches, checking the voltage on each switch, both on & off. Everything appeared normal so I removed the nav lights to make sure there was nothing burned out or corroded - all was fine in there.

I'm sat scratching my head wondering what to check next, and figured the only bit I hadn't really checked was the length of wire that comes out of the centre console (from the switch) and runs into the A-Frame to supply the nav lights. The wire itself is wrapped in something like heat-shrink protective wrapping, but what I spotted was that the wire going into the heat shrink is black, but the wire that comes OUT of the heat-shrink is white, so there's obviously a join somewhere....

SO - switch is definitely on, and I started squeezing the shrink along it's length until I found where the wires are joined. Gave it a squeeze and it's like Blackpool Illuminations behind me!

A bit of fiddling with the join, and a tight wrap with self-amalgamating tape, and it's as good as new :-) SO happy that I managed to get a couple of hours to mess about on the boat, AND I fixed the issue!!

So what I can I fix next.....?? I was thinking (!), the switch controls the P & S lights and the all-round white light on top. If I wanted to display just the white light when anchored, is it going to be a total ball-ache to somehow get that switched seperately? Not a huge issue if it is, as it's quite unlikely we'll ever be out beyond dusk, but it'd be nice to know.

Cheers all for your guidance - love this forum!!