Bio-Diesel

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TBOT422
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Joined: Sun Jun 26, 2011 5:36 pm
Location: Clearwater, FL

Bio-Diesel

Post by TBOT422 »

Is anyone running bio-diesel in their engines? I had a discussion this weekend with the owner of a Catalina 31 with a Universal 26 engine. He claims he is mixing 10% bio-diesel in with regualr street diesel fuel and it makes the engine run much smoother. He said that before he started using the bio-diesel the engine had a very rough idle (as many of us have encountered). After mxining in about 10% bio-diesel he said the engine smoothed out and ran like a sewing machine. He even dropped his idle RPM from the recommended 1000-1200 RPM for his engine down to 900 RPM, and it still purred like a kitten. I found this interesting because I have had rough idle problems with the M-35 in our C350 and found that by increasing the RPM about 100-150 RPM to around 1100 RPM the engine smoothed out and the helm floor quit vibrating. Hopefully that also reduced the wear and tear on the other components that seemed to be deteriorating due to vibration (fuel filter bracket, heat exchanger brackets, fuel lift pump, etc.) Possibly bio-diesel is a better solution? Does anyone know the difference between street diesel, marine diesel, and bio-diesel?
Gary & Janet
The Best of Times (Hull #422)
wolfe10
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Re: Bio-Diesel

Post by wolfe10 »

Best advice, you don't want our opinions on this. I am saying that as the guy who presents the Caterpillar RV Diesel Engine Maintenance Seminars around the country.

You should contact Westerbeke and/or Kubota.

Most manufacturers have specs on maximum percent bio-diesel.

And we are talking about bio-diesel-- there are mil specs for it. NOT homemade french fry oil.

And different years may have different tolerances to bio-diesel. I know Caterpillar does.

Also, be aware that bio-diesel often breaks loose any dirt/debris in the fuel system. So, yes, I guess it could clean a clogged injector, but not sure it would do a thing for an engine that is OK (maintained; run under load, not just at or slightly above idle, etc) Switching to bio-diesel means check the fuel filters often for the first 25 or so engine hours.

Brett
Last edited by wolfe10 on Sun Mar 18, 2012 9:13 pm, edited 1 time in total.
Brett Wolfe
C350 #180
"Vindaloo"
Ft Myers FL
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TBOT422
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Re: Bio-Diesel

Post by TBOT422 »

Thanks Brett,

I knew I could count on your opionion. I thought it was a bunch of hoey. Although if I have time, I might contact Westerbeke and see what they have to say. I'm not really sure where I could buy any bio-diesel in the first place if it really did make any sense.
Gary & Janet
The Best of Times (Hull #422)
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TBOT422
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Location: Clearwater, FL

Re: Bio-Diesel

Post by TBOT422 »

Just for the record here was the response from Westerbeke:
Westerbeke Corporation neither approves nor disapproves of the use of Bio-Diesel with our marine diesel products. We donot recommend a mixture greater than 10%. We are not aware of any maintenance scheduale changes from those listed in the Operator’s Manual for the M35B when using Bio-Diesel.

Any engine operating issues that might result from the use of a Bio-Diesel mixture you would need to approach the Bio-Diesel manufacturer.

Kind Regards,
Westerbeke Corp.
My guess is that using Bio-Diesel in a diesel engine is similar to using bio-fuels (Ethanol) in a gasoline engine - all sorts of seals, etc. may have future problems.
Gary & Janet
The Best of Times (Hull #422)
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