jrudge
Well-Known Member
Before you do any long legs on a boat you need to know it's proven fuel burn and adjust that taking into account the weather ( rough seas use more fuel ) and state of the hull / props.
Identicial Volvo Penta TAMD63P with different fuel burn rates
- Thread starter Ariane
- Start date
Bandit
Well-Known Member
Firstly running a trip where your reserve margin is only 200l is very marginal. I run same engines in two boats. It sounds like props are not matched or Gearbox ratios different. I de pitched a prop when I hit a tarpaulin so other engine fuel burn increased significantly.
Check engine oil level for both engines has one increased which could indicate hosing.
Check both props are they damaged, are they the same pitch and diameter?
Check rpm indecently from gauges.
Start with the basics and don’t jump to conclusions.
Check engine oil level for both engines has one increased which could indicate hosing.
Check both props are they damaged, are they the same pitch and diameter?
Check rpm indecently from gauges.
Start with the basics and don’t jump to conclusions.
Sticky Fingers
Well-Known Member
@Elessar your 74Ps report different fuel burn per side I recall.
DavidJ
Well-Known Member
I think @Chris_d point is worth pursuing
I remember having a problem with one engine and increasing the revs on the other to compensate and noticed an increase in temperature on the harder working engine. (and presumably greater fuel consumption). What I didn’t feel is a difference in steering. I guess we instinctively correct the wheel to go straight due to variables of tide, wind etc so in the same way we probably won’t notice the correction we make with engine to engine power difference.
As for me the problem was in fact with the other engine (turbo was my problem) not the higher temp/higher fuel consumption engine.
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jrudge
Well-Known Member
Every now and then I un intentionally have mismatched rpm ( the system will match RPM but only if the levers are close to each other) and other than looking at the dials there is nothing you would notice handling wise.
I have no idea as to the physics behind this but the props are close together and at speed I suspect you would need a gross mismatch to notice much. The sea is dynamic with waves, wind etc so neutral rudder would not glee a straight line passage and you are always making corrections.
I have no idea as to the physics behind this but the props are close together and at speed I suspect you would need a gross mismatch to notice much. The sea is dynamic with waves, wind etc so neutral rudder would not glee a straight line passage and you are always making corrections.
kashurst
Well-Known Member
Sounds like one engine is working harder than the other. The engine that used less fuel is getting an easy ride either because:
The hard working engine has a more fouled prop or a tighter water seal/stuffing box
Or the easy ride engine is not getting enough air or fuel.
My kamd300s would do this when the starboard engine fuel filter became more blocked than the port one. (Boat and kamd specific scenario)
I had similar on a pair of 63p but never really solved it completely.
The hard working engine has a more fouled prop or a tighter water seal/stuffing box
Or the easy ride engine is not getting enough air or fuel.
My kamd300s would do this when the starboard engine fuel filter became more blocked than the port one. (Boat and kamd specific scenario)
I had similar on a pair of 63p but never really solved it completely.
gordmac
Well-Known Member
How do you know the steering was exactly central?