Shibaura Engine running generator

[zzjea]

While under the genset, I can access the starter via a trap door (panel) that can be removed. It gives me limited access to the starter and with difficulty, the 2 solenoids tucked up and hard to get to. I noticed the starter was engaged into the flywheel sprockets and I turned the starter sprockets and the flywheel turned also. Surprised me as I did not expect it to be engaged while not active and that I could turn everything by just my fingers. I thought there would be a lot of compression or other resistance involved.

It will take another try to see if the starter will run at a continuous speed when jumped. It has never done that even when I could get it to start. It was always a hit and miss trying to coax the starting process to work. Like I said before, if I can get the thing to start, it runs perfectly and powers a 7.5kw generator flawlessly.

 

[zzjea]

At this point, I would not be concerned if it starts. I would want to see it turning over at a nice speed.

You are not jumping it to start at the starter. Just feeding it there. Normally the B+ goes from the battery to the starter. So you go straight to the starter. Same idea with the ground.

I don't understand how t he flywheel can be easy to turn even with the starter engaged. Please explain.

You sure you didn't get a 24 volt starter or something like that?

Any diesel I know of has a good amount of resistance to crank it, even before hitting compression. The fact, that that flywheel jumps 90 or so degrees so effortlessly leaves me puzzled.

Doing some reading. It's a nice engine, sought after in that generator.

The new starter is an OEM from Generac. Same part number and labeling as the original, 12v.

 

[WranglerX]

"....The starter is trying veeery hard to turn the engine over and acts like it is low on amps. I have put 2 new starters in it thinking that was the problem. I have also put in a new starter solenoid and they are connected to 4 6v batteries in series near the rear of the MH. The MH with an ISB Cummins (300hp) has 2 12v batteries to start that engine. The crossover switch to connect all 6 batteries does not help with starting the Shibaura. I have not tested the amp draw at the battery yet as it is a little difficult to do. The batteries (4 6v) are charged up and produce 12.5-14v if plugged in to shore power (120vac) via the converter. However, obviously I want to be able to run the generator when not on shore power.>>>

This statement really confuses me, is the MH system 24 volt being a diesel? ........ Is generator 12 of 24 volt.....It is not really clear to me... But sounds like it is also 24 volt.....

Starter sounds like you are trying to crank it with 12 volts and its a 24 volt starter...... . But then I am new to diesels.... IF just trying to jump it with 12 volts and its a 24 volt starter, you are just wasting your time....

Dale

 

[zzjea]

"....The starter is trying veeery hard to turn the engine over and acts like it is low on amps. I have put 2 new starters in it thinking that was the problem. I have also put in a new starter solenoid and they are connected to 4 6v batteries in series near the rear of the MH. The MH with an ISB Cummins (300hp) has 2 12v batteries to start that engine. The crossover switch to connect all 6 batteries does not help with starting the Shibaura. I have not tested the amp draw at the battery yet as it is a little difficult to do. The batteries (4 6v) are charged up and produce 12.5-14v if plugged in to shore power (120vac) via the converter. However, obviously I want to be able to run the generator when not on shore power.>>>

This statement really confuses me, is the MH system 24 volt being a diesel? ........ Is generator 12 of 24 volt.....It is not really clear to me... But sounds like it is also 24 volt.....

Starter sounds like you are trying to crank it with 12 volts and its a 24 volt starter...... . But then I am new to diesels.... IF just trying to jump it with 12 volts and its a 24 volt starter, you are just wasting your time....

Dale

All systems on the motorhome are 12v including the generator circuits. Also, sometimes I have gotten it to crank but not consistently.

 

[searcyfarms]

you have either a bad connection or a low power situation, those shibaura motors a golden !!!! i would have unhooked those cables coming from the back and hooked up some jumper cables to it and see how it spins with a known good battery/ground then u have solved your issue of proving the power/ground then just work on those two things. My 16hp 3 cyl shibaura only used a 360cca 12 volt battery for starting and it had glow plugs - no reason it should be horribly difficult to start you are just not getting enough power/amps to spin it

 

[Gem99ultra]

Even a weak battery in your series will knock down the staying power of the set. Even though all the batteries may test out to be a full 6.0+ volts, at least one probably has one or more dead or weak cells. Lots of work to pull those batteries for testing, but I sure think that's where your problem lies.

 

[zzjea]

Even a weak battery in your series will knock down the staying power of the set. Even though all the batteries may test out to be a full 6.0+ volts, at least one probably has one or more dead or weak cells. Lots of work to pull those batteries for testing, but I sure think that's where your problem lies.

I jumped the genset directly from a running car battery (14v) with same results. No house batteries were used or MH wiring from batteries. A direct connection was used via a heavy duty jumper cable set.

 

[zzjea]

Can a solenoid work properly at times or is it either good or bad period? Could the starting solenoid only be allowing partial amperage to get to the starter? Really hard for me to test this.

 

[grsthegreat]

What size cables are running from the batteries. The voltage drop during starting is way too much. The amperage draw from the starter may not be available from the batteries if cabling is too small. My dodge diesel had some starting issues before I replaced factory cables with aftermarket 2/0 cables. Then it started like a dream. But it takes 2 - 750 amp batteries to fire it up. I personally think that a 12 volt run over 30 feet is the issue. Even cheap jumper cables can prevent a diesel from starting. My jumper cables are also at least a 1/0 or 2/0 copper wire... and there only 12 feet long.

After glow plugs run their cycle, I generally only see a 1 volt or so loss of dc voltage during start cycle. If your dropping down to 8 ish you not allowing enough volts to starter. As voltage drops, the amperage increases and wires arnt allowing it to pass.

 

[zzjea]

What size cables are running from the batteries. The voltage drop during starting is way too much. The amperage draw from the starter may not be available from the batteries if cabling is too small. My dodge diesel had some starting issues before I replaced factory cables with aftermarket 2/0 cables. Then it started like a dream. But it takes 2 - 750 amp batteries to fire it up. I personally think that a 12 volt run over 30 feet is the issue. Even cheap jumper cables can prevent a diesel from starting. My jumper cables are also at least a 1/0 or 2/0 copper wire... and there only 12 feet long.

After glow plugs run their cycle, I generally only see a 1 volt or so loss of dc voltage during start cycle. If your dropping down to 8 ish you not allowing enough volts to starter. As voltage drops, the amperage increases and wires arnt allowing it to pass.

The house battery cable is about 1/2" thick with copper wire about 3/8" thick, don't know the gauge. My jumper cables weigh about 20# and thickness of copper is at least 1/4". If the glow plugs are pulling too many amps, that would leave less for the starter.