Beta BV1505 glow plug advice please

[Chunk]

Hi All,

Recently my year 2000 Beta BV1505  has been reluctant to start from cold after giving 15 seconds of glow plug heating, the battery seems ok with good cranking speed.

The resistance of each plug is 1.2 ohms which I believe is ok?

The voltage measured at the battery drops from 12.7v to 12.1v whilst powering the glow plugs.

The voltage measured at the glow plug rail is 8v with a current flow of 24A.

The +ve supply comes off the battery connection at the starter through a multi-plug, 40A inline fuse, through the ignition switch, back through the multi-plug to the glow plug heater rail a run of around 5M all in 2.5mm cable.

This cable size seems very small, to the point where a 5M run at 30A  will drop the calculated voltage by over 2V, in my case nearer 4V?

Does anyone have any ideas on increasing the voltage and therefore current flow to the plugs? I could increase the cable size to reduce the volt drop but I guess Beta have limited the current for a reason? But it seems I have lost a couple more volts than I should have.

Any ideas would be great thanks

 

 

[David Mack]

I would check/clean the connections on the multiplug and fuse first.

[WotEver]

I’d also try replacing the black relay. They only cost a couple of quid and the contacts don’t last forever. 

[WotEver]

51 minutes ago, Chunk said:

This cable size seems very small, to the point where a 5M run at 30A  will drop the calculated voltage by over 2V, in my case nearer 4V?

2.5mm over 5m @ 30A will only drop a volt. Your problem is connections along the way. 

Check each glow plug too - they should each have a cold resistance of 0.55 ohms. If you find one that’s infinite then it’s burned out. 

[Boater Sam]

The glow plugs are dissipating about 48 watts each, but the wiring and connections between the battery and the plugs is dissipating 100 watts, that's too much, and something will be getting warm. You may be able to feel a hot connection after the plugs have been energised for a while.

Check all connections, and the ignition switch and relay. The multiplug is a known problem. Relays do get burnt contacts. You could try linking across from the relay contact for the heaters to the plugs with a decent piece of cable to bypass the two multiplug connections, and see if it is better.

Edited April 10, 2018 by Boater Sam
added more

[Dr Bob]

26 minutes ago, Boater Sam said:

The glow plugs are dissipating about 48 watts each, but the wiring and connections between the battery and the plugs is dissipating 100 watts, that's too much, and something will be getting warm. You may be able to feel a hot connection after the plugs have been energised for a while.

 

Ah, a job for the infrequent red thermometer!

[Chunk]

Thanks for the suggestions I'll give them a try today

[Sea Dog]

Check your manual Chunk.  Whilst 15 secs isn't an unusual glow plug heating time, I'm pretty sure my Beta 42 says no more than 10 secs.  Your 1505 may well be different, but it's worth a look so you don't roger them.

[Jen-in-Wellies]

1 hour ago, Sea Dog said:

Check your manual Chunk.  Whilst 15 secs isn't an unusual glow plug heating time, I'm pretty sure my Beta 42 says no more than 10 secs.  Your 1505 may well be different, but it's worth a look so you don't roger them.

It is 10s in the Beta 43 manual. Mind you a 43 in reasonable condition will start from cold without them, just a little more smokey. 

Better to check the resistance with a multimeter through the chain of switch, relay, plug/socket first to find the area of poor contact that is reducing voltage to the plugs. Confirm if necessary, or investigate further with the system energised for the shortest times possible and double check with voltage readings. You'll need two people ideally for voltage readings. One on the key switch and the other working the meter.

Jen

[Sea Dog]

2 hours ago, Jen-in-Wellies said:

It is 10s in the Beta 43 manual. Mind you a 43 in reasonable condition will start from cold without them, just a little more smokey. 

 

This is indeed true. Can't remember when I last used my heater, certainly not yesterday. Thanks for not being pedantic about my 42/43 error Jen - I did know what engine I had really! 

[Dr Bob]

28 minutes ago, Sea Dog said:

 Thanks for not being pedantic about my 42/43 error Jen - I did know what engine I had really! 

Ah but it did not go unnoticed

[Sea Dog]

5 minutes ago, Dr Bob said:

Ah but it did not go unnoticed

The engine was definitely noticed yesterday as it made noises and we moved. I did think it might be about 1HP down though, hence why I wrote 42,  but it was just shallow water effect and the engine is running as sweetly as ever. That's my excuse and I'm sticking to it.

[Chunk]

Disconnecting and reconnecting the multi plug has increased the voltage to over 10 at 36 amps and with the circuit fused at 40 amps I guess it couldn't take much more? We'll see if it improves things.

One comment I'd make is the multi plug has no latching device to hold it together an isn't exactly a tight fit, also I don't have the manual and can't find the exact one online so unsure of max glow time, maybe someone with a bv1505 could chime in?

thanks for the advice

[ditchcrawler]

Dont know if this Kubota info helps http://www.kubota.com.au/wp-content/uploads/2015/10/D905.D1105.V1505.D1105-T.V1505-T.pdf

 

Just found this from Beta http://betamarine.co.uk/wp-content/uploads/downloads/operators_manuals/1680-75105-HEKC-SOM-0414.pdf

Edited April 11, 2018 by ditchcrawler

[Boater Sam]

We see lots of these multi plugs on Betas held together with Zip ties......................wonder why?

[Chunk]

Thanks Ditchcrawler and Boater Sam,

I'll limit to 15 seconds and whip out some cable ties

[Jen-in-Wellies]

2 hours ago, Chunk said:

One comment I'd make is the multi plug has no latching device to hold it together an isn't exactly a tight fit, also I don't have the manual and can't find the exact one online so unsure of max glow time, maybe someone with a bv1505 could chime i

It is a very common for them to come apart while cruising from the vibration. Thwe engine carries on running just fine, but the rev counter and instruments go off and the electric stop solonoid doesn't work so you have to know which bit of the engine to poke to get the engine to stop. As Boater Sam says, zip ties get used a lot. Mine is wrapped in insulating tape to hold it together.

Jen