Generators again - this must be daft, please tell me why!

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Morpheous

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So after my last thread on the chances of resurrecting a Panda 4, I'm looking at all the possible options.

On ebay you can buy a 6.5 KVa portable diesel generator with electric start. Surely it would be possible to take one of these out of its frame, remove the fuel tank and stick it where the panda will exit.

This must be daft because other wise everyone would be doing it - please enlighten me :-)

I have a manual start button on my fuse board so not too worried about auto start. Noise I suspect could be an issue?
 
Noise would be pretty horific. You would need sound insulation and baffling. Vibration may also be a problem - you will need very compliant feet - I mean the generator will anyway. Otherwise go for it.
 
vibration - big issue, noise suppression, put it in a box full of sound deadening, then you will need to keep it cool, and finally vent the exhaust safely.
 
WhiteMischief said:
exhaust not a problem.
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Are you sure? It will be very noisy due to not exhausting underwater and the exhaust fitting will be very hot where it exits the hull (potentially, multiple 100s of deg C). And you wont be able to fit a sound box because you need airflow over the rad to cool it. Might be better to get a small petrol unit for now?
 
jfm said:
Are you sure? It will be very noisy due to not exhausting underwater and the exhaust fitting will be very hot where it exits the hull (potentially, multiple 100s of deg C). And you wont be able to fit a sound box because you need airflow over the rad to cool it. Might be better to get a small petrol unit for now?
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OK. Fit a small Jabsco pump and exhaust elbow to inject water and cool the exhaust. Use a silencer from Halyard or Vetus. Make a baffled sound box. This means air can get in and out but the baffling reduces the noise. If it is a water cooled unit, a small heat exchanger could be used and then you would only need a silenced air intake for the engine itself.

Next problem?;)
 
I assumed I would use the same exhaust as the panda 4, no idea if that is below the water. A little petrol is a possibility, just don't think it would be man enough for the hob
 
Bassplayer said:
OK. Fit a small Jabsco pump and exhaust elbow to inject water and cool the exhaust. Use a silencer from Halyard or Vetus. Make a baffled sound box. This means air can get in and out but the baffling reduces the noise. If it is a water cooled unit, a small heat exchanger could be used and then you would only need a silenced air intake for the engine itself.

Next problem?;)
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Yup, I agree you could do all that (though I'm not sure I would!). I don't think such a soundbox would make much difference to the noise and a seawater heat exchanger would be better with a more sealed soundbox. I was really just questioning the "exhaust no problem" statement!
 
Those framed generators are air cooled, the panda and others would have been liquid cooled, much quieter, the water jacket absorbs alot of noise. Was the panda a 1500 rpm unit? the framed gensets are usually 3000rpm - noisier still.

Cooling would be a big concern
 
I read the link from latestarter, but to be honest FP do make good sets but not in the marine world.

I have at home a 12kv unit from a bbc outside broadcast van that is water cooled everywhere and sits in a case the same as the marine versions, but the whole of the exhaust is stainless steel and shows no signs of corrosion, I bought it with a view to fitting a heat exchanger as its been cooled with a roof mounted radiator and pumped with a central heating pump, it has a 4 cylinder kubota engine, it would be ideal in a barge or narrow boat as it could be very easily keel or tank cooled and will never rot away.

I see the main cause of failure is sea water and little else, my advise is to buy a closed cooled unit next time.
 
These cheap units for sale on fleabay and other retail outlets working on price, work on price for a reason, they are often cheap and nasty, have a short lifespan, and very poor regulation.

Much better to save the pennies a little longer and get a reputable brand which will cost twice as much, last ten times longer, and save yourself lots of hassle.

One other alternative is to build your own, alternators are readily available as self exciting, self regulating units and simply need connecting to a diesel engine.
 
volvopaul said:
I read the link from latestarter, but to be honest FP do make good sets but not in the marine world.

I have at home a 12kv unit from a bbc outside broadcast van that is water cooled everywhere and sits in a case the same as the marine versions, but the whole of the exhaust is stainless steel and shows no signs of corrosion, I bought it with a view to fitting a heat exchanger as its been cooled with a roof mounted radiator and pumped with a central heating pump, it has a 4 cylinder kubota engine, it would be ideal in a barge or narrow boat as it could be very easily keel or tank cooled and will never rot away.

I see the main cause of failure is sea water and little else, my advise is to buy a closed cooled unit next time.
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FP from 2004 do have closed cooling, however the mind set of the numpties who designed such a crazy system is still the same. They were utter junk, now just junk.

MOD did, and possibly still do purchase FP gennies all on price rather than technical merit, however their life is measured in hundreds of hours not thousands of hours of the reputable brands.
 
You will already have 2 large gennies on board, both diesel, normally pushing your boat forward or reverse. These have sufficient alternator power to charge your batteries, and at idle are probably quieter than most stand alone diesel gennies. Why not bung on a couple more domestic batteries, with a low voltage alarm, and start one or both engines when they need a top up? This route will save a few quid, save a lot of hassle with the installation, and give you reliable power. You might then augment with a smallish petrol gennie which you stow in the anchor chain locker at the sharp end, which I think vents straight out ot atmosphere, rather than the bilge, eliminating any danger of petrol fumes....................or have I missed something?
 
I think you have a good idea and probably the idea of taking the genny out of the frame, is a bit of lateral thinking.
I would look at Mobos with diesel generator fitted, and what steps were taken to ensure minimal noise and vibration. Copying what is known to work is not plagiarism, it is good common sense
 
rafiki_ said:
You will already have 2 large gennies on board, both diesel, normally pushing your boat forward or reverse. These have sufficient alternator power to charge your batteries, and at idle are probably quieter than most stand alone diesel gennies. Why not bung on a couple more domestic batteries, with a low voltage alarm, and start one or both engines when they need a top up? This route will save a few quid, save a lot of hassle with the installation, and give you reliable power. You might then augment with a smallish petrol gennie which you stow in the anchor chain locker at the sharp end, which I think vents straight out ot atmosphere, rather than the bilge, eliminating any danger of petrol fumes....................or have I missed something?
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This is definitely my plan B if the P4 is not repairable. The only thing I have found in the past is that the engines need to run a long time to catch up with domestic usage, probably because they should also charge the starter batteries.

Adding another domestic battery will be a must.
 
WhiteMischief said:
This is definitely my plan B if the P4 is not repairable. The only thing I have found in the past is that the engines need to run a long time to catch up with domestic usage, probably because they should also charge the starter batteries.

Adding another domestic battery will be a must.
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You could also up spec one or other of your engine alternators, if you are concerned about the recovery rate. You can also fit a gismo that improves the efficiency of the std ones, a lot cheaper as well.
 
Albert, do you have an endless supply of old worn records? Some of us like our toys. If you take your point to first principle, chop in your raggie for a coracle!
 
Until recently my boats had no toys at all, although I did splash out on a tacktic. Now swmbo comes along we need fridge, heating, kettles etc. Ah well, life moves on
 
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