Phil Symonds is struggling to find out why the engine revs on his yacht keep falling away. PBO's Stu Davies has the answer

I’ve had the ownership of a lovely 2008 model Jeanneau Sun Odyssey 42DS for the past four years.

I’m delighted with the boat, she is roomy and beautiful to sail.

However, like all things man-made she has little technical niggles that crop up from time to time.

I was out sailing recently about 30 miles from home when the wind died and I needed to motor back.

The 50hp Yanmar is a really good, clean engine with very few hours. She performs best around 5.5 knots at 2,500rpm, but the throttle would not hold or stay at that rpm.

A throttle handle on a boat which delivers engine revs

The Teleflex throttle control lever on Stu Davies’s own yacht

Instead, I coaxed 1,800rpm which only gave 4 knots. I could not get the engine to stay at the required revs.

I looked online to see if anyone else has had the same experience and while many had, none referred to Jeanneaus in particular or the control mechanism.

I believe the controls are Teleflex/Morse but the model I cannot say.

I emailed Jeanneau and got a quick reply, but despite giving all the details saying that I needed to find a way to tighten up the friction on the cables or mechanism, Jeanneau suggested I should take the boat to my nearest Jeanneau dealer, which in my case is either Lisbon or Huelva – a minimum of 100 miles .

Are you aware of where the friction mechanism might be?

Some are on U-shaped friction plates on the engine – mine definitely doesn’t have that – or on the control lever itself on the cockpit bulkhead?

Although it’s not urgent, any advice would be helpful to me and I suspect other Jeanneau owners, especially those who live miles from their nearest dealer!

Phil Symonds

Stu Davies replies:

The control on Phil’s boat is a Teleflex 700 series, used in lots of boats including mine.

I have had mine apart to replace the little red knob sticking out and at first it was a bit of a puzzle as to how it came apart.

Basically, there is an Allen grub screw at the bottom of the handle which is loosened and then the lever can be gently wriggled off its splined shaft.

The square plastic cover can then be flipped off with a screwdriver – it’s only held on with some plastic tags.

Continues below…

A careful perusal of the boss that the splined shaft comes through reveals a grub screw which can be tightened to apply some friction onto the shaft to address the looseness issue.

While it’s apart, some lubrication of the sliding components and cables wouldn’t go amiss.

Reassembly of the unit is then quite straightforward and the job is done.

Enjoyed reading Engine revs sliding away: PBO’s engine whisperer has the answer!?

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