Volvo Penta 2001 engine speed control

[Yara]

Vintage diesels- dont you love them!
I have been pottering over Covid lock downs, but now is the time to actually sail the boat. Engine starts easily, but idles slowly, bouncing around. Worse, when put into gear, the bouncing makes the shaft knock, not a good feeling. I have bought a rev counter, and next time on the boat will check the actual idle revs compared to the manual recommendation of circa 800 RPM.
Now here is the problem: the idle screw is pretty much screwed all the way in. So much so that the PO has moved the lock nut to an impossible position on the far side of the bracket. I am thinking of getting a longer screw, but also that something must be sloppy for this situation to happen. Of course, access to the control quadrant is impossible as it is hard up against a bulkhead. I have glimpsed an ephemeral exploded parts drawing on the internet, but could not establish what the connection between the control quadrant and the actuating shaft is. Hopefully there is some dear PBO reader out there who has pulled one of these VP2000 series apart, and can give me an insight into what the likely cause of the problem is.

 

[penfold]

It's a single cylinder engine; they dance the watusi at idle even when everything is exactly as it should be. That said engine mounts are worth looking closely at for general deterioration or oil contamination-related perishing.

 

[Stemar]

Download the workshop manual here: https://avdhoeff.home.xs4all.nl/zei...enta-Type_2001-2002-2003T_Workshop-Manual.pdf

If the "something sloppy" is due to internal wear which, given the age of the engine must be a possibility, I doubt it's worth the investment, even if you can get the parts, so I'd be inclined to get that longer screw and start saving for a replacement.

Do check the engine mounts, though - a new set would be worth doing if they're knackered

 

[[70521]]

Vintage diesels- dont you love them!

We sure do. Far less to go wrong with them and what does go wrong is mechanical and fixable. Some of the modern common rail stuff is a nightmare.

Delighted owner of a 40 year old VP2002 here.

 

[Yara]

We sure do. Far less to go wrong with them and what does go wrong is mechanical and fixable. Some of the modern common rail stuff is a nightmare.

Delighted owner of a 40 year old VP2002 here.

Hi Sandy,
Good to hear that you are happy with your engine. I have the workshop manual but it does not clearly show the quadrant details. The 2002 speed control is the same as the 2001. So if you can get access to the side of the control quadrant, does it look like it attaches to the shaft with a spline, square end or something like that?

 

[[70521]]

Hi Sandy,
Good to hear that you are happy with your engine. I have the workshop manual but it does not clearly show the quadrant details. The 2002 speed control is the same as the 2001. So if you can get access to the side of the control quadrant, does it look like it attaches to the shaft with a spline, square end or something like that?

I am down at the boat this week and will try and get some pictures.

The VP2000 range is basically the same engine, but with one, two or three pots.

 

[Dantp]

As suggested above Check the mounts and the alignment.
Ours was out of alignment and after realigning and tightening all the mounting bolts it was much much smoother.
(I was surprised how far out it was as the last time I checked it was perfect with no adjustment)
(We have a VP 2003)
If you want to check the engine speed there are apps for your phone. I used acoustic tachometer (android). Agreed nicely with my rev counter.

 

[Yara]

Turns out that there is a lever for the speed control, and the floppyness is sideways. There is a kind of spring circlip, but it is too weak to hold the arm in place. The nut the PO put on the end of the adjustment screw is to pick up the arm when it is out of alignment. Adjusted the idle rpm to around 850 as per manual, but there is still a prop shaft knock as I put her into gear and the revs drop. Guess next is replace engine mounts.