Volvo Penta 2003 throttle sticking

[eebygum]

The throttle on my Volvo Penta 2003 is not throttling back after accelerating ?

The boat is a Beneteau 35s7 with a single morse lever in the cockpit. The engine starts fine and I can engage neutral, forward and reverse but as I increase the revs and throttle back the engine remains reving at the maximum point reached. I can go down into the engine bay and manually pull the lever on the engine to throttle back.

So the problem seems to be that the accelerator cable can increase the revs but not decrease, the lever on the engine which controls the revs is not retracting when powering back.

What are the mechanics by which the lever on the engine reduces the revs ? Is it the cable movement. There is a small spring on the end of cable which looks like it should be pushing back the lever against the force of the cable ? (I've tried lubricating and the spring on the cable moves freely but maybe it needs replacing ? ). I'm assuming the problem is at the engine connection rather than the morse lever, is that a valid assumption ?

I'm away from the boat now but hope to return next weekend to fix so any ideas gratefully received.

If it helps here is a picture of the cable connection at the engine.

Thanks in advance.

 

[Gwylan]

Look forward to seeing what the replies are. We had a similar problem.

Then one day leaving the pontoon something happened. Basically the cable broke at the Morse end - no engage gear or revs control. We were left being pushed by the wind and tide onto a neighbouring boat. That's what fenders are for. Could have been a lot worse.

Turns out it is a stiff wire rather than a cable - well ours is.

Give it a good looking at and carry a spare so you can effect a replacement relatively quickly - just need to disassemble the helm - and thread the new cable etc.

Cost us best part of day, finding and engineer, the spare and fitting.

Await others input.

 

[sailorman]

The throttle on my Volvo Penta 2003 is not throttling back after accelerating ?

The boat is a Beneteau 35s7 with a single morse lever in the cockpit. The engine starts fine and I can engage neutral, forward and reverse but as I increase the revs and throttle back the engine remains reving at the maximum point reached. I can go down into the engine bay and manually pull the lever on the engine to throttle back.

So the problem seems to be that the accelerator cable can increase the revs but not decrease, the lever on the engine which controls the revs is not retracting when powering back.

What are the mechanics by which the lever on the engine reduces the revs ? Is it the cable movement. There is a small spring on the end of cable which looks like it should be pushing back the lever against the force of the cable ? (I've tried lubricating and the spring on the cable moves freely but maybe it needs replacing ? ). I'm assuming the problem is at the engine connection rather than the morse lever, is that a valid assumption ?

I'm away from the boat now but hope to return next weekend to fix so any ideas gratefully received.

If it helps here is a picture of the cable connection at the engine.

Thanks in advance.

Change the Morse cable yours is all bent up

 

[Tranona]

It is either the cable or the mechanism behind the Morse control lever that needs cleaning and greasing.

 

[VicS]

Change the Morse cable yours is all bent up

On the top arm ? That's the stop "cable".

 

[alahol2]

Check the clamps that hold the outer sheath of the morse cable, both ends, on the engine and at the throttle lever. Also check the attachment of the inner cable at both ends. Sounds like the lock nut on the inner has screwed back from the attachment point allowing the cable to pull but not push.

 

[Skipper_Christoph]

+1

 

[BabaYaga]

I'm assuming the problem is at the engine connection rather than the morse lever, is that a valid assumption ?

As I understand it on this engine increasing the revs is by a pulling action of the cable, so it seems far more likely that something is wrong at the morse control connection.

 

[pvb]

I suspect the cable needs replacing; I had to do the one on mine a couple of years ago. The cables don't last forever and aren't repairable. Be sure to measure the cable carefully before buying a replacement. Replacement cables are easily obtainable from VP dealers, marine engineers, etc.

 

[2copplane]

In the photo the morse cable is attached to the lower lever and has shiny stainless washers and bolt. The top lever and cable is the engine stop. Get someone to move the morse control back and forth and see if that lower lever moves accordingly.
If not then it maybe that the outer sheath of the cable isn't clamped properly, or perhaps the cable is snapped so can only push and not pull, or not attached properly at the morse control.
I'd suggest you consider changing both morse cables for throttle and gear change as it must be one of the most common reasons I see for breakdowns in yachts and not very expensive.

On my old 2003 i had an issue that when cold it was sometimes really sluggish to rev. I did open the throttle body up once and inside was some kind of guide with return springs that I suspected was getting stuck, never did fix it, just let the engine warm a little.

 

[Andrew G]

I too suspect the cable may be broken. With "somone" watching the control lever in the cockpit see if you can move the throttle (the lower lever with the shiny washers and black insulating grommets in your pic.) forward. If it moves relatively easily and without the control lever moving the cable is broken (as 2copplane suggests). Easy to replace once you have the new ones (there will be a third one going to the gear box). Andrew

 

[DJE]

My 2002 did the same thing and your photo looks like the problem I had. Basically there was a bit of corrosion where the throttle lever passes through the casing into the engine. A mechanic friend of mine took off the cover plate where the two levers are mounted, dismantled the levers cleaned and lubricated everything and re-assembled it all. Then slapped me round the head and told me to give the lever pivots regular sprays with WD40. It's been fine since. Your photo looks a bit dry and corroded around the lever pivots. Try dribbling some light oil around there and working the levers backwards and forwards.

 

[pvb]

My 2002 did the same thing and your photo looks like the problem I had. Basically there was a bit of corrosion where the throttle lever passes through the casing into the engine. A mechanic friend of mine took off the cover plate where the two levers are mounted, dismantled the levers cleaned and lubricated everything and re-assembled it all. Then slapped me round the head and told me to give the lever pivots regular sprays with WD40. It's been fine since. Your photo looks a bit dry and corroded around the lever pivots. Try dribbling some light oil around there and working the levers backwards and forwards.

I'm surprised by this, because the Teleflex cable is a positive push/pull force. If, as in the OP's case, the throttle setting won't reduce, but he can move the engine connection manually, surely it would point to a cable problem?

 

[DJE]

I'm surprised by this, because the Teleflex cable is a positive push/pull force. If, as in the OP's case, the throttle setting won't reduce, but he can move the engine connection manually, surely it would point to a cable problem?

To clarify, the problem with mine was somewhat different to that described by the OP. The engine would respond to the controls when opening and closing the throttle except that it would not return fully to idle. It wouldn't run at less than 1000 to 1200 rpm. I suspect that the spring at the end of the throttle cable was compressing due to the resistance in the lever pivot.

 

[pvb]

To clarify, the problem with mine was somewhat different to that described by the OP. The engine would respond to the controls when opening and closing the throttle except that it would not return fully to idle. It wouldn't run at less than 1000 to 1200 rpm. I suspect that the spring at the end of the throttle cable was compressing due to the resistance in the lever pivot.

So, a different fault.

 

[DJE]

So, a different fault.

Maybe a different fault. Maybe the same fault to a different degree.

 

[jonrarit]

The engine would respond to the controls when opening and closing the throttle except that it would not return fully to idle. It wouldn't run at less than 1000 to 1200 rpm.

My 2003 does exactly this too (fast idle)..... not got to the bottom of it yet but have found a quick "blip" (with the neutral button pressed) brings the idle back down to normal

JR

 

[alahol2]

My 2003 does exactly this too (fast idle)..... not got to the bottom of it yet but have found a quick "blip" (with the neutral button pressed) brings the idle back down to normal
JR

I had this problem on a different engine. I think it comes down to a worn control lever box. A simple and cheap fix is to add an extra return spring to the throttle lever on the engine. I just used a coil spring I had lying around one end attached to the engine throttle lever the other to the engine bay frame. Has been working for the last eight years.