lack of performance!!

flipper1

New Member
Joined
8 Mar 2004
Messages
10
Location
Surrey, UK
Visit site
My parents have a Fairline Targa 30 down in the med with Volvo Kad32 duoprop engines. It was only taken there last year and was nearly new then, prior to that they had never tried it prior to buying it over in the UK. Problem is a total lack of acceleration. The boat just feels v.v. sluggish and needs full throttle to get anywhere near the plane. The engines have been serviced and will rev freely out of gear. Any ideas whether this is most likely to be a problem of fuel, air, temperature, wrong props or something else. I would assume the boat was performing satisfactorily in the UK before my parents bought it. I know it could be any of these but the lack of performance is very marked. Has anyone experienced simialr problems and solved them?

<hr width=100% size=1>Harvey White
 
What's the hull condition andn are the props clean? I would lookthere first if you are (what sounds like) 10 knots down on performance and the engine revs freely out of gear.

<hr width=100% size=1>
 
hull was spotless, props perfect condition, top speed prob only 5kts below what i seem to remember was exoected

<hr width=100% size=1>Harvey White
 
Injectors?

We were told by volvo that the first sign of an injector needing attention is not being able to make top revs under load.

Does each engine reach the same amount of revs? Or is one lagging?

<hr width=100% size=1>Alex

boat2.jpg

<A target="_blank" HREF=http://www.mad-als.com>http://www.mad-als.com</A>
 
We did injectors which increased the rpm to the required level but as we did prop repitch at the same time it is impossible to determine the precise effect of either procedure.

Nick

<hr width=100% size=1><A target="_blank" HREF=http://arweb.co.uk/argallery/Nick2>http://arweb.co.uk/argallery/Nick2</A>
 
You say the hull WAS spotless,has it been sitting in the water for a while?

<hr width=100% size=1>No dear,the water goes in the other one.
 
Hi Harvey, welcome to the forum. How long has the boat been in the water? If more than 6 months it will need a scrub, weed grows all year round in med. because of the temp. I had the same problem. Also check fuel filters, as engines will rev freely without load, but sludge/growth in fuel will starve engines under load. Regards David.

<hr width=100% size=1>Sea water is for boating on, not swimming in.
 
Just a thought....

If boat was supplied for UK waters, then your olds choose to ship it down to the med, did it keep the same DP propellers???

The reason for asking is because in the med the ambient air temp is so hot, so the engine air temp is hot and as such the engine can loose some performance. As such the next size down props would be fitted in order to maintain close to the original performance. So say the boat has A7 fitted in UK, you may need to consider changing to A6 in the Med.

However... As no doubt other posters have mentioned, I know I should read it all first, if the boat's bottom is slightly dirty or worse still really dirty, you will loose performance by the truck load.


<hr width=100% size=1>
 
bottom was def. spotless. engines only done 150 hrs, so would have hoped the injectors werent shot, so maybe props if the answer. just need one size down to make up for the v. hot weather?

<hr width=100% size=1>Harvey White
 
Check for diesel bug. We lost performance drastically on one engine under load due to blocked filters, but it would make max revs off load, like DavidBunn said. Quite why we didn't lose both is a mystery...

<hr width=100% size=1><-- insert witty sig file here -->

<A target="_blank" HREF=http://www.fairlinetarga29.info>Buy my boat!</A>
 
Surely, if it's pulling the revs and the bottom is clean, and it's trimmed correctly and not overloaded, that's the definition of top speed?

<hr width=100% size=1>
 
exactly!

and changing the props down will (or should) resolve the out of the hole performance but will not give you more speed than currently if you are pulling full revs with the higher pitch.

Loading could welll be a factor but 5 knots on a boat that size? Loaded plus a months growth but surely not on a clean hull.

Seems to me you need to establish if you have a problem first before looking for solutions - log the revs/speed against loading and discuss with the manufacturer; they will tell you straight away if you are 'within tolerances' or have a problem to be resolved.

<hr width=100% size=1>
 
Top