Westerbeke 8.0 gen-real gph?

Any actual readings available?

no of cylinders? Displacement? 1800 rpm?

Full load around 1gph, but it is rare for any boat to run the gennie at full for any length of time. Typical boat load averaged out would be more like 2-4kW where it would burn about 0.3 to 0.5gph.

Ski in NC said:

Full load around 1gph, but it is rare for any boat to run the gennie at full for any length of time. Typical boat load averaged out would be more like 2-4kW where it would burn about 0.3 to 0.5gph.

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Corresponds with my results. However, Bay Pelican was set up to load the generator by using two chargers for a shorter period of time.

Agree with SKI with my old WB 8BTD. Rarely run more than a few hours per day so the fuel tank levels barely moved.

I had an 8KW Westerbeke I always figured 1gph and was never disappointed because it burned less.

Thank you for your responses. I’ll use 1/2 gph for my calculations

meridian said:

Thank you for your responses. I’ll use 1/2 gph for my calculations

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That's a scary underestimation if you are travelling a long distance.

24 gallons a day versus 12 gallons a day (24 hour running) could mean a lot when traversing longer distances. Not to mention running to an area for cheaper fuel.

I have always used 1gph on my 8.0. I only have 330 gallons usable and I burn 5 gph for both engines without the genny and 6 total when running it.


Rather have and not need than need and not have.

Ski in NC said:

Full load around 1gph, but it is rare for any boat to run the gennie at full for any length of time. Typical boat load averaged out would be more like 2-4kW where it would burn about 0.3 to 0.5gph.

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+1

Ski in NC said:

Full load around 1gph, but it is rare for any boat to run the gennie at full for any length of time. Typical boat load averaged out would be more like 2-4kW where it would burn about 0.3 to 0.5gph.

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Real close to my experience also.

I run an 8kW Kubota/Onan ex-marine unit as my shop/house hurricane back-up gennie. I'm at the "end of the line" when it comes to power line, so last to get power back after a storm.

Last fall's hurricane Flo we were out of power for over two weeks. We ran the gennie continuously and it burned about 10-12gal a day. Right at 0.5gph. Two 55gal drums with dipstick to measure. Pretty accurate. Ran two 24kBtu/hr AC's, but they did not run continuous, cycled as normal. Had to turn off AC's to run water heater (4.5kW), but would only do that once a day for like an hour.

I figure about 5kW when both AC's are on. We had quite a few guests staying upstairs so that unit ran quite a bit. Amazing how many friends you have when you have AC and they do not!!

Once weather cooled down we would shut it off at midnight, then back on at sunrise. Got down to about 5gal/day as AC's did not come on as much. Modern fridge did not like it, though.

So I have a fair amount of data regarding what a 8kW will burn!! The Westy 8 with Mitsubishi motor will burn about the same.

Ski in NC said:

I run an 8kW Kubota/Onan ex-marine unit as my shop/house hurricane back-up gennie. I'm at the "end of the line" when it comes to power line, so last to get power back after a storm.

So I have a fair amount of data regarding what a 8kW will burn!! The Westy 8 with Mitsubishi motor will burn about the same.

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How did you cool the engine and generator ???

Small radiator from a Geo Metro with an electric fan. Back of manifold blocked off with steel plate with nipple for dry exhaust via muffler to outside of shop. Sea water pump removed and port blocked off. HX removed. Welded a steel frame to support radiator.

Ski in NC said:

Small radiator from a Geo Metro with an electric fan. Back of manifold blocked off with steel plate with nipple for dry exhaust via muffler to outside of shop. Sea water pump removed and port blocked off. HX removed. Welded a steel frame to support radiator.

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Problem solved, thanks

I monitor the burn on my Kohler 8KW as best I can by keeping track of hours run between fill ups. It pulls from the port side tank, as does the port engine. The Stb engine pulls from the Stb tank, and I always run both motors. So, in theory, the fuel difference between the port tank and stb tank is what the gen-set burned. I know it's far from perfect, but over time I think it averages out to be pretty accurate. I almost always burn just over .25 gph, right at .3 gph. I allow for .5 gph just to be safe. I've never seen it at 1 gph.


In the summer we generally put about 8 hours per day on the generator, since we run the AC at night. Less in the cooler months.

A pretty reliable formula is that you will burn 1 gal for every 10kwh generated, or 1 gph per 10kw of load.