3YM30 starter doesn't engage

[Slowboat35]

Disregard my stuff about the fuse.
I've only just noticed (d'uh oh!) it's a YM. My remarks re fuse referred to the GM series where that is a known issue. I can't speak for YMs.

Oops! Sorree!

 

[[163233]]

Disregard my stuff about the fuse.
I've only just noticed (d'uh oh!) it's a YM. My remarks re fuse referred to the GM series where that is a known issue. I can't speak for YMs.

Oops! Sorree!

I wouldn't be so sure, the YMs and GMs are very similar.

 

[179580]

Tip from an old engineer. Turn key to start position and hold for 5-10 seconds. Feel all the cables, problem is where the heat is. Worked for me.

 

[VicS]

I wouldn't be so sure, the YMs and GMs are very similar.

ITYWF the fuses are in diffrrent locations Physically and electrically. In the engine compartment in the case of the 1GM10. In the panel in the case of the 3YM30

In the case of the YM bad connections on the fuse would not cause the symptoms described

From the point of view of circuit protection the GM has a fuse in the correct location. The 3 amp fuse in the YM panel only protects the warning lights alarm and tacho.



......... .....................

 

[[163233]]

In the case of the YM bad connections on the fuse would not cause the symptoms described

Much more different than I was expecting. My money is still on a failed crimp causing a short when he turns the key.

Perhaps we should have a sweepstake?

 

[Boater Sam]

Tip from an old engineer. Turn key to start position and hold for 5-10 seconds. Feel all the cables, problem is where the heat is. Worked for me.

I was going to suggest that but did not want to set his GRP boat on fire!

 

[Boater Sam]

Much more different than I was expecting. My money is still on a failed crimp causing a short when he turns the key.

Perhaps we should have a sweepstake?

I'll bet either battery or a bad connection on battery cables pos or neg or the isolator switch US

 

[179580]

I was going to suggest that but did not want to set his GRP boat on fire!

It will only get warm , not catch the boat alight.

 

[farmer.leo]

All of the ideas were much appreciated. Here is an update.

Using a remote starter the engine runs fine, one alligator clip to the starter + terminal and the other capturing the small white wire. Turning the panel on first to get the alarm sound, press the remote starter for less than a second, and it starts. This also enables the panel to shut down the engine. Worked well enough but not a long term solution.

Pulled the 3A fuse behind the yanmar keyswitch panel and it's fine. Perhaps I knocked a wire loose while cleaning up the bilge.

I'll report back once the problem is solved.

 

[VicS]

All of the ideas were much appreciated. Here is an update.

Using a remote starter the engine runs fine, one alligator clip to the starter + terminal and the other capturing the small white wire. Turning the panel on first to get the alarm sound, press the remote starter for less than a second, and it starts. This also enables the panel to shut down the engine. Worked well enough but not a long term solution.

Pulled the 3A fuse behind the yanmar keyswitch panel and it's fine. Perhaps I knocked a wire loose while cleaning up the bilge.

I'll report back once the problem is solved.

This suggests that the key switch might be faulty. OK until you turn to the start position then goes tits-up.

Can you clip the remote starter onto the white wire and the incoming red on terminal 30 on the back of the keyswitch without shorting everything out (There is no negative there so it should not be too hazardous)

Or just jump a wire beween the two. ( clip one end onto the red, switch on and just touch the other end onto the white )

 

[farmer.leo]

Can you clip the remote starter onto the white wire and the incoming red on terminal 30 on the back of the keyswitch without shorting everything out (There is no negative there so it should not be too hazardous)

Or just jump a wire beween the two. ( clip one end onto the red, switch on and just touch the other end onto the white )

The remote starter is currently jumping from the battery feed on the starter solenoid to the little white white just inches away.

Are you suggesting a jump wire from the panel down to the engine?
Or are you suggesting a jump wire behind the panel, connecting red to white there bypassing the key switch?

 

[PaulRainbow]

The remote starter is currently jumping from the battery feed on the starter solenoid to the little white white just inches away.

Are you suggesting a jump wire from the panel down to the engine?
Or are you suggesting a jump wire behind the panel, connecting red to white there bypassing the key switch?

Behind the panel, connect the positive to the white wire. If it starts, it's likely the switch, if not it's likely a break in the white wire.

 

[VicS]

The remote starter is currently jumping from the battery feed on the starter solenoid to the little white white just inches away.

Are you suggesting a jump wire from the panel down to the engine?
Or are you suggesting a jump wire behind the panel, connecting red to white there bypassing the key switch?

The latter
On the key switch jump from the incoming red on terminal 30 to the white on terminal 17

Switch on, activate the glow-plugs briefly ........ it would be relevant to check that the glow-plugs are actually being energised at this stage ....... then jump 30 to 17 to find out if the warning lights and buzzer stay on ( as they should) and the engine cranks( No need to actually crank it 'til it starts if you don't want too)

If the problem persists then there is almost certainly a bad connection somewhere in the power supply ( the red wire) to the panel. If the engine cranks then the problem must be a defective key switch , but test it before buying a new one.

If it is difficult to jump 30 to 17 connect a volt meter to terminal 30 and a convenient negative (ie the black wire on the back of the tacho) Attempt to start in the usual way while monitoring the volts. If the volts stay normal the power supply is good and the keyswitch is suspect but if they collapse when the key is turned to "start " it suggests a bad connection in the power supply to the panel

 

[VicS]

Behind the panel, connect the positive to the white wire. If it starts, it's likely the switch, if not it's likely a break in the white wire.

A break in the white wire would not cause the warning lights to go out and the buzzer to stop sounding as described in #1

 

[PaulRainbow]

A break in the white wire would not cause the warning lights to go out and the buzzer to stop sounding as described in #1

You're right, i hadn't looked back at post #1. So we're back to checking the panel positive supply and the switch, my money is on the positive supply.

A simple test would be a length of wire to a known good positive (battery/isolator/busbar etc) and the positive terminal of the switch.

 

[Koeketiene]

The engine has the control panel with a key and the warning lights, they come on as normal with the buzzer. However, when the key is turned to start there is nothing. No sound, not even a click. And the engine panel goes dark. When the key is turned back into the start position, the panel lights come back on with the buzzer.

Hoping this is an easy fix, perhaps something came loose.

Had the very same problem with the very same engine (Yanmar 3YM30) about 3 weeks ago.

Apparently, the problem is a known Yanmar issue.
At fault is a relay to the starter engine. (picture of the part below)

The relay was removed and replaced by an automotive alternative bought from Norauto (French Halfords) for €8.50
It's been faultless so far, though I have been advised to replace it with a Yanmar part 'as soon as convenient'.

Hope this is of some help to you.

 

[VicS]

You're right, i hadn't looked back at post #1. So we're back to checking the panel positive supply and the switch, my money is on the positive supply.

A simple test would be a length of wire to a known good positive (battery/isolator/busbar etc) and the positive terminal of the switch.

You could be right , which is why I continue to consideri it as a possibility
BUT
The reason I think it could be the keyswitch is that the starter solenoid is activated by a relay ( #24 in the schematic) , not directly from the key switch therefore the current flow is not that great
The glowpluga and the stop solenoid are also operated by relays . The OP reports no abnormality when activating the glowplugs and when stated (by jumping a power supply directly to the white ) he was able to stop it normally with the stop button.
Maybe the starter relay takes a much higher current that the other two although there's no reason why it should

Had the very same problem with the very same engine (Yanmar 3YM30) about 3 weeks ago.

Apparently, the problem is a known Yanmar issue.
At fault is a relay to the starter engine. (picture of the part below)

The relay was removed and replaced by an automotive alternative bought from Norauto (French Halfords) for €8.50
It's been faultless so far, though I have been advised to replace it with a Yanmar part 'as soon as convenient'.

Hope this is of some help to

I think being able to start it as described in # 29 suggests that this relay is probably OK

 

[farmer.leo]

Had the very same problem with the very same engine (Yanmar 3YM30) about 3 weeks ago.

Apparently, the problem is a known Yanmar issue.
At fault is a relay to the starter engine. (picture of the part below)

The relay was removed and replaced by an automotive alternative bought from Norauto (French Halfords) for €8.50
It's been faultless so far, though I have been advised to replace it with a Yanmar part 'as soon as convenient'.

Hope this is of some help to you.

View attachment 95864

Thanks for the info.

I recognize that part, it's on the top rear center of the engine. Perhaps a good test would be to jump the relay there. Are the two
large terminals supposed to be jumped momentarily to engage the starter?

It looks like there are two smaller terminals above them, do you know what attaches there?

 

[LiftyK]

As relays have been mentioned, let me share a tip. My trusty Yanmar 1GM10 stopped being trusty at the start of last season. The local yard then fitted an additional relay, the well known fix mentioned in an earlier thread. It was cheap and effective.

Last week I was on a sailing trip when the wind picked up way beyond forecast, which seems to be common at present. To help with reefing, I went to start the engine. Turning the key produced the usual buzzer sound but pressing the starter button dud not spin the engine. I sailed to a sheltered spot, anchored, and looked at the engine where after much prodding I found one of the spade connectors on the new extra starting relay was loose. I squeezed it up, the engine started and continued on my way.

The point of this story is that over the next week, each time I repeatedly had to open the engine bay and squeeze with pliers each relay contact until the engine start worked. Where the relay was cable tied, it was shaken by the engine and no amount of spade squeezing would give me a reliable start.

Now I have added solder to the spade connectors, which I appreciate should not be necessary, and bolted the relay to the engine compartment wall rather than leave it clipped to the engine and its shaking.

 

[alan]

As already said (Posts #8 & 11) the small round relay on the rear of the engine are a known source of problems on these engines. My boat gave this starting problem intermittently for a long period; eventually I bought a new relay and after cutting the cable tie on the wires to the old relay one of the spade connectors dropped out of its mate! Seems like it was like this from new. Also the the Sunsail base mechanic (in Procida in Italy) told me these relays also have a habit of sticking 'on' which causes the starter motor to be engaged permanently, and a number of charter boats had burnt out their starter motors because they became permanently engaged.

Despite the theories, my money is on this relay or the wiring to/from it. Clean all the connectors on the wiring especially any extension cables you may have between the engine and the control panel. These Yanmar 'block' connectors are not the best quality!!

Good luck,
Alan.