Genset Question

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boodaghost

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I upgraded boats back in November to a boat with a 5kw Kohler genset.
Not at all familiar with the operation of a genset and am wondering what the minimum amount of fuel the tanks can have and the thing still run.
It fired off fine when I cranked it and then went dead after about 30 seconds and wouldn't crank again. The boat (Chris Craft 328) only has about a quarter of fuel in each tank.

I guess that I'm asking what the average minimum would be for one of these to run. I may be answering my own question by saying that I would think that a quarter tank would be a good measure of safety to get you home on.
Anyone???
 
Silvertip

Silvertip

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Re: Genset Question

Get you home on? The genset does not push the boat so that's rather odd fuel quantity question. The engine should run with 1/4 tank. It should also run until the tank goes dry. It probably has a fuel shutoff located somewhere close to the tank in the fuel line. The engine ran 30 seconds until it used the fuel in the carb and quit. Use a fuel system treatment like SeaFoam or Stabil in EVERY tank of fuel and by all means, exercise the generator often.
 
B

boodaghost

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Re: Genset Question

Very well aware that the genset doesn't push the boat.
The question is all anbout the genset, not the engines. The same tanks that feeds the I/O's also feed the genset.
If the genset is allowed to run until the tanks are empty, then you have no fuel for the engines. I think that it's pretty standard for a boat with a generator to have that generator's fuel pick up installed in a way that keeps you from running the tanks/tanks dry.

Roughly, how low does the fuel level in the tank get to that the genset quits picking up fuel? Is there a "standard"?
 
R

rbh

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Re: Genset Question

The ones that we have been looking at just tee off the mainline.
umm, does your genset have a sea **** that needs to be turned on so that the gensets impellor can pull water in to cool it and remove exhaust?????
Just like your boats motor it must have a supply of water going to it or stuffs going to happen. :eek:
 
seabob4

seabob4

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Re: Genset Question

The pick-up on your fuel tank for the genset will be the same depth as the ones for the motors. The manufacturer, in this case Chris Craft, does not determine how long YOU can run your genset. That is up to you to know your remaining fuel quantities and run the genset and your motors accordingly.

Did you do the obvious like check the shut-off valves on the pick-up(s)? Since you said "tanks", I'm assuming you have 2 tanks, and the genset can draw off either. Do you have a fuel manifold that allows either motor or the genset to draw off either tank? If you do, you need to see where the position of the shut-off and cross-over valve handles are. It may just be a case of a valve that's closed...
 
B

boodaghost

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Re: Genset Question

RBH, Yea, I've opened the sea-**** and the water was a pumpin' fine.

SEABOB4, You may be onto something with shut off valves that feed fuel to the thing. I thought about water flow but not fuel flow. This might explain it only ran for only a few seconds. I could understand that it would use up the fuel this side of the shut off valve in about the time that it did. Not sure of the fuel manifold though. I'm still in the process of learning exactly how the thing works.

I'm still wondering about the pick up line that feeds it though. When we were shopping for the boat, we looked at a 2000 Sea Ray 290 that was very low of fuel. The genset wouldn't run. We were told that the genset fuel line was installed in a way that would prevent it from completely draining the tank (could have been a line of BS, don't know). Alas, fuel to get home on. If we're dealing with a Tee'd fuel line to the engines. Then what you say would be exact.

HUGE THANKS for all input!
 
seabob4

seabob4

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Re: Genset Question

Booda,
Look around your engine room and see if you can find a series of shut-off valves grouped very close together and mounted probably vertically, with a number of fuel lines coming in and going out from them. That would be your fuel manifold. A good builder will allow each engine AND the genset draw off of either tank. When I was at Stamas Yacht, we had an option for a third tank, and with twins and a genset, you about needed a road map to figure out all the valves. We labeled all the lines and valves, but it was still confusing to the layman...;)
 
R

rbh

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Re: Genset Question

+1 on sea bob idea,
as well could there be a petcock mounted to the genset around the carb??
 
seabob4

seabob4

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Re: Genset Question

rbh said:
+1 on sea bob idea,
as well could there be a petcock mounted to the genset around the carb??
Click to expand...

RBH,
Not to say there isn't one, but I've done too many Kohler installs to speak of, and never have I heard nor seen of such an animal...once again, not to say there ISN'T one...

We switched over to Westerbeke a few years ago, as today's Kohlers have a cat converter coming off the exhaust elbow that adds about 18" to the end of the elbow. Exhaust configuration would have been a nightmare! Not to mention, Westerbeke's are so quiet, you don't need a sound shield, which can eat up valuable real estate as well...
 
smokeonthewater

smokeonthewater

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Re: Genset Question

My Carver has one pickup for the engine that reaches all the way to the bottom and one pickup for the genset that only reaches to about 1/4 tank

My Wellcraft has one pickup for each engine that reaches the bottom and a third for the genset that only reaches to about 1/4 tank

My old motorhome had two tanks the engine could empty either but the genny could only draw the aux tank down to 1/4

These are the only vehicles with gensets I have ever owned.... if the 1/4 limit being common thing is bs then I need to buy a lottery ticket or get life ins or something
 
B

boodaghost

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Re: Genset Question

Well done all!
I gave the fuel lines the once over this afternoon and as best I can tell, carb, metal line, rubber line with filter, and straight into the starboard tank. No from of cut-off. As this boat has L/R tanks, I suppose that it's possible that the p/u line goes to the bottom of the tank.

SMOKEONTHEWATER, however, seems to validate what I was told. If I have time tomorrow, I'm going to take a five gallon tank of fuel (fuel dock is closed when I leave work) and load it in the starboard tank. Both tanks are showing right at a quarter. Hope that it will be enough.
I'll post my finding.
 
seabob4

seabob4

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Re: Genset Question

smokeonthewater said:
My Carver has one pickup for the engine that reaches all the way to the bottom and one pickup for the genset that only reaches to about 1/4 tank

My Wellcraft has one pickup for each engine that reaches the bottom and a third for the genset that only reaches to about 1/4 tank

My old motorhome had two tanks the engine could empty either but the genny could only draw the aux tank down to 1/4

These are the only vehicles with gensets I have ever owned.... if the 1/4 limit being common thing is bs then I need to buy a lottery ticket or get life ins or something
Click to expand...

Smoke,
I have only been in the boat building business for 16 years (Wellcraft. Hydra-sports, Intrepid, Stamas, Proline) and have never heard of such a thing...I even deal with RDS Aluminum on a personal level...

Learn something new everyday...
 
smokeonthewater

smokeonthewater

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Re: Genset Question

well the dates here MAY be the key. You have been in the business for 16 years and the newest example I gave is 21 years old.... this may be a failsafe feature that has fallen by the wayside in recent years in favor of less expensive manufacturing practices...
 
seabob4

seabob4

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Re: Genset Question

Smoke,
When we get our tank from RDS, let's say for a 35 Express with triple engines and a genset, there will be plugs in 2 of the pickups, as the standard boat comes with twins and no genset. We pull out the plugs and install fuel barbs, 3/8" for the third engine, 1/4" for the genny. There is no particular pickup they specify is for the genny. Maybe it is an old practice that should be reinstituted...
Shruggingshoulders.gif
 
L

Lyle29464

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Re: Genset Question

The pickup on my generator is about one inch above the engine pickup. I thought all boats were like this. It is a great fool proof notice that your low on fuel.

Anyway most all generators have at least 3 sensors that will let the engine start and run a few seconds. Then anyone one of the 3 will shut the engine down if the exhaust gas is too hot, the oil pressure is too low or the engine overheats. A bad sensor will do what your is doing. You can look in the manual and fine the wire that kills the engine. just unhook it for a minute to test engine. But I would check the gas supply first.
 
B

boodaghost

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Re: Genset Question

I added 5 gals tonight to no avail. Time allowed me to remove the rubber fuel line that was attached to the metal line that was an oem part of the genset.
There was no fuel in it.
Had I been using my head, I could have blown into it and listened for any girgling within the tank. I hope to try this tomorrow. I'll assume that girgling means that I might have a bad fuel pump or other.
Whatever the case, I plan to hit the fuel dock this weekend and, hopefully, settle the debate over how deep the fuel pick-up goes, in at least, this particular vessel.
 
smokeonthewater

smokeonthewater

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Re: Genset Question

most pickups I have encountered have spring loaded check balls so blowing may not work... the best test is to unscrew the pickup from the tank and measure it
 
B

boodaghost

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Re: Genset Question

I finally managed to fuel the boat today. Genset still doesn't run.
Again, I unhooked the fuel tube at the genset and it was dry.

I have about three feet of tubing that starts at the genset, then what appears to be a fuel filter, then another eighteen inches of the same type fuel tubing into what is some kind of three inch long brass fitting that is attached to the elbow that has the actual pick-up line down into the tank.

I think that I'm dealing with some kind of clog via fuel filter or three inch brass thing or the fuel pump is giving me the finger.

Had I known at the time to do it, I was told to put my finger over the fuel pump inlet and turn the engine over. If I felt any suction, then the fuel pump wasn't the issue. I ran out of time today or I would have tried it.
 
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