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post #1 of 2 Old 06-04-2014 Thread Starter
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Rough running

Our boat has a Westerbeke 20B30 diesel. Has been well maintaned, starts easily, never smokes and generally runs well.

Buy it certainly has speeds where it seems to run better than others and I wonder if this is normal. It runs wonderfully at 1000 rpm, but gets pretty lumpy at 800, which is where the idle was set. I turned the idle screw up to 900 and that seems OK.

But as power it up ( in neutral) it runs smooth to maybe 1700 rpm, then is lumpy from 1700 to 2000 rpm, but then smoothed back out and runs good from 2100 on up.

Is this normal? What might be the cause? I don't have very much diesel experience so don't know where to start.

When I say, 'lumpy', I mean it sounds rougher and certainly bucks around a bit more on its mounts too. I thought maybe it had to do with prop shaft alignment but since it happens in neutral as well as in gear, that seems unlikely.


Thanks for your help.

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post #2 of 2 Old 06-04-2014
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Re: Rough running

sounds like my b20.been told its normal. I try not to run it at thosr certain revs. if all else is good, as you ssaid; like me ...learn to live with it. iirc, they arr all tractor motors .never. met a tractor motor that don't have lumps


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'80 Watkins 27
North East, MD
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