Electric start technique for Yanmar YSE 12

[eebygum]

OK, I’ve read the Yanmar manuals (RTFM done) and still cannot figure this out, so to save my sanity please any suggestions....

I’ve bought a boat with an old but very well maintained Yanmar YSE 12 engine which I’ve. successfully started through hand cranking and it runs sweetly.

My question is when electric starting do I need to open the decompression lever and drop once it’s turning over ?? (The manual suggests I do but I would need very long arms or a stick to do this !!!)

With the starter motor.... batteries are fully charged, (1) Oil and Charge lights are on, turning key to start... (2) starter motor clicks.... (3) then whirrs up the fly wheel and turns a couple of times and stops without firing up. On subsequent attempts it may only get to step 1 or 2.

I think there might be a problem with starter motor but I’m trying to rule out operator error on the technique as the manual suggest you need to move the decompression lever too.

Thanks in advance for any suggestions.

Cheers,

 

[Spyro]

Could be a problem with the starter or possible connections between starter button and starter solenoid. To rule out any connection problems take a jumper lead from the battery +ve direct to the connection on the starter solenoid. If it turns over ok then the starter is ok. At least you know the engine starts and runs ok as you,ve done it by hand which by the way isn't easy, well done. You shouldn't need to operate the decompression lever when using the starter unless you have a very weak battery.

 

[VicS]

Could be a problem with the starter or possible connections between starter button and starter solenoid. To rule out any connection problems take a jumper lead from the battery +ve direct to the connection on the starter solenoid. If it turns over ok then the starter is ok. At least you know the engine starts and runs ok as you,ve done it by hand which by the way isn't easy, well done. You shouldn't need to operate the decompression lever when using the starter unless you have a very weak battery.

If that is so why does the instruction manual quite clearly tell you to raise the decompression lever ?

 

[Spyro]

If that is so why does the instruction manual quite clearly tell you to raise the decompression lever ?

I said used to have a yse8 never needed to do that. As the op says virtually impossible to do on your own unless you can reach the star button while holding open the decompression lever

 

[pvb]

I used to have a yse8 never needed to do that. As the op says virtually impossible to do on your own unless you can reach the star button while holding open the decompression lever

The manual shows a remotely-operated decompression lever for electric starting.

 

[eebygum]

Yes Spryo.. that makes more sense, there is a cable connector on the Decompression lever but it’s not connected to anything at the moment (which me wonder how the previous used to electronic start).

 

[Spyro]

The manual shows a remotely-operated decompression lever for electric starting.

Give a rest. I said shouldn't have to. I've told the OP I had the same engine and it started fine without using the decompressor

 

[pvb]

Give a rest. I said shouldn't have to. I've told the OP I had the same engine and it started fine without using the decompressor

Sorry I offended you by explaining how Yanmar intended the decompression lever to be operated for electric starting. I thought the OP might find it useful. Obviously I was wrong.

 

[Spyro]

Sorry I offended you by explaining how Yanmar intended the decompression lever to be operated for electric starting. I thought the OP might find it useful. Obviously I was wrong.

Sorry about that. I've Pm you but your inbox is full.

 

[VicS]

OK, I’ve read the Yanmar manuals (RTFM done) and still cannot figure this out, so to save my sanity please any suggestions....

I’ve bought a boat with an old but very well maintained Yanmar YSE 12 engine which I’ve. successfully started through hand cranking and it runs sweetly.

My question is when electric starting do I need to open the decompression lever and drop once it’s turning over ?? (The manual suggests I do but I would need very long arms or a stick to do this !!!)

With the starter motor.... batteries are fully charged, (1) Oil and Charge lights are on, turning key to start... (2) starter motor clicks.... (3) then whirrs up the fly wheel and turns a couple of times and stops without firing up. On subsequent attempts it may only get to step 1 or 2.

I think there might be a problem with starter motor but I’m trying to rule out operator error on the technique as the manual suggest you need to move the decompression lever too.

Thanks in advance for any suggestions.

Cheers,

You say the battery is fully charged but is ita "good" battery that is capable of delivering the high current that the starter motor requires. If in doubt get it tested as there is no point in proceeding if the battery is no good.

If the battery is good check and clean all the connections not forgetting the battery switch and the negative connections.

Bypassing the battery switch will eliminate the possibility of bad contacts therein.

Spyro suggests using a jump lead from battery +ve direct to the connection on the starter solenoid. but he does not say which connection on the solenoid.
Directly to the starter motor connection should spin the motor but it will not engage with and crank the engine if it is a pre-engage type of starter unless the solenoid coil is also energised .

Starter motor brushes may be worth checking together with the state of the commutator. The Service manual gives a figure for the minimum brush length ( 9.5mm IIRC, but check)

The YSE 12 is a larger capacity engine than Spyro's YSE 8 so may not start so easily although the 1kW output stater motor really should have no difficulty cranking it provided the battery is a good one and all connections are sound

It may be worth investigating fitting remote operation of the decompression lever as pvb has noticed is shown in the instruction book.

 

[Laysula]

I had a yse 12. always started on the button and I never used the decompressor.

 

[Spyro]

You say the battery is fully charged but is ita "good" battery that is capable of delivering the high current that the starter motor requires. If in doubt get it tested as there is no point in proceeding if the battery is no good.

If the battery is good check and clean all the connections not forgetting the battery switch and the negative connections.

Bypassing the battery switch will eliminate the possibility of bad contacts therein.

Spyro suggests using a jump lead from battery +ve direct to the connection on the starter solenoid. but he does not say which connection on the solenoid.
Directly to the starter motor connection should spin the motor but it will not engage with and crank the engine if it is a pre-engage type of starter unless the solenoid coil is also energised .

Starter motor brushes may be worth checking together with the state of the commutator. The Service manual gives a figure for the minimum brush length ( 9.5mm IIRC, but check)

The YSE 12 is a larger capacity engine than Spyro's YSE 8 so may not start so easily although the 1kW output stater motor really should have no difficulty cranking it provided the battery is a good one and all connections are sound

It may be worth investigating fitting remote operation of the decompression lever as pvb has noticed is shown in the instruction book.

You'd have to put the jump lead on the solenoid connection that comes from the starter button. That would be the thinner of the cables

 

[VicS]

You'd have to put the jump lead on the solenoid connection that comes from the starter button. That would be the thinner of the cables

The white wire in this diagram then