Volvo MD 2030 experts Help please!!

Natterjack

Natterjack

Member
Joined
29 Dec 2011
Messages
41
Location
Isle of Wight
www.dibbensremovals.co.uk
Hi all,

I've been trying to sort out an engine problem for nearly a year now without success.

I now suspect the problem may lay with the regulation system located behind the timing cover

For the experts out there I’ll try to explain as fully as possible

Symptoms are as follows

1. At correct idle speed, engine stalls when fwd or rev is engaged (instantly reduces rpm by 200rpm and then continues to reduce until stalled)
2. At correct engine idle setting, engine won't start. (does start easily if throttle is increased)
3. When running at idle there is very little or no increase in engine speed for the first part of the throttle range. i.e. pushing the throttle arm on the engine against the spring.
4. Acceleration appears to be slow in neutral from idle to WOT
5. Acceleration is slow in gear
6. Max rpm in fwd gear around 2,000 - 2,200 tied up, and 2,500 - 2,900 under way

Observations

1. With engine set to approx' 1000 - 1050rpm, engine starts as it should, does not stall when fwd is engaged (rpm drop by approx 100rpm in gear)
2. Engine speed has been checked with laser tacho.
3. Engine does not smoke including at WOT, in gear

Entire fuel system cleaned, exhaust elbow and back pressure checked, injectors and lift pump replaced and high pressure pump repaired.

Any advice or known common faults with the regulation system would be greatly appreciated!!
Thanks in advance, Dan
 
Looking at your location I'd be tempted to get an engineer out to diagnose the problem. If you explain at the outset that you're intending a DIY resolution they'll understand. You pay them an hourly rate which compares well with the motor industry!

Years ago I used RK marine to diagnose a problem. They were great. Even suggested a cheap radiator shop to get the exchanger stack tested.
 
Ruffles said:
Looking at your location I'd be tempted to get an engineer out to diagnose the problem. If you explain at the outset that you're intending a DIY resolution they'll understand. You pay them an hourly rate which compares well with the motor industry!

Years ago I used RK marine to diagnose a problem. They were great. Even suggested a cheap radiator shop to get the exchanger stack tested.
Click to expand...

Thanks, I have had a VP mechanic have a good look and he was stumped! (It was on his advice injectors/Injector Pump were tested & replaced).
I have also contacted a couple of local engineers but there is busy until end May/June!
 
The symptoms you describe sound very much to me like a governor issue.

The governer is not compensating for increased load on the engine, and consequent drop in revs, by giving it a bit more fuel to maintain constant revs.

Similarly that's why it's not starting at the idle setting.

As the governor is normally sealed with wax to prevent tampering, and is normally factory set it's something best left to a competent VP dealer or engineer. May need dismantling or adjustment.
VolvoPaul of this parish would be a good start.
 
Kylema 2 said:
Hi all,

I've been trying to sort out an engine problem for nearly a year now without success.

I now suspect the problem may lay with the regulation system located behind the timing cover

For the experts out there I’ll try to explain as fully as possible

Symptoms are as follows

1. At correct idle speed, engine stalls when fwd or rev is engaged (instantly reduces rpm by 200rpm and then continues to reduce until stalled)
2. At correct engine idle setting, engine won't start. (does start easily if throttle is increased)
3. When running at idle there is very little or no increase in engine speed for the first part of the throttle range. i.e. pushing the throttle arm on the engine against the spring.
4. Acceleration appears to be slow in neutral from idle to WOT
5. Acceleration is slow in gear
6. Max rpm in fwd gear around 2,000 - 2,200 tied up, and 2,500 - 2,900 under way

Observations

1. With engine set to approx' 1000 - 1050rpm, engine starts as it should, does not stall when fwd is engaged (rpm drop by approx 100rpm in gear)
2. Engine speed has been checked with laser tacho.
3. Engine does not smoke including at WOT, in gear

Entire fuel system cleaned, exhaust elbow and back pressure checked, injectors and lift pump replaced and high pressure pump repaired.

Any advice or known common faults with the regulation system would be greatly appreciated!!
Thanks in advance, Dan
Click to expand...

What are you saying the correct idle speed should be? I have the Perkins Perama version of this and as far as I am aware the idle speed should be around 950-1000 revs.My engine loses 200 revs when I engage gear and causes a lot of vibration due to low revs until I rev it up.This I put down to slack in the throttle cable ie not increasing revs when load comes on engine.But this doesnt seem to answer your problem of engine revs decreasing.
 
The maximum revs you can achieve shows lack of fuel rather than drag on the prop or blocked air supply, both of which would cause black smoke at full throttle.

Have you checked the simple things like part blocked fuel pipe? We all tend to go for the more expensive and complicated causes first.

But tbh it sounds very much like a problem with the pump / high pressure pump / rack etc even though you have had these repaired / serviced. You need a really competent diesel guy not me.
 
Kylema 2 said:
Hi all,

I've been trying to sort out an engine problem for nearly a year now without success.

I now suspect the problem may lay with the regulation system located behind the timing cover

For the experts out there I’ll try to explain as fully as possible

Symptoms are as follows

1. At correct idle speed, engine stalls when fwd or rev is engaged (instantly reduces rpm by 200rpm and then continues to reduce until stalled)
2. At correct engine idle setting, engine won't start. (does start easily if throttle is increased)
3. When running at idle there is very little or no increase in engine speed for the first part of the throttle range. i.e. pushing the throttle arm on the engine against the spring.
4. Acceleration appears to be slow in neutral from idle to WOT
5. Acceleration is slow in gear
6. Max rpm in fwd gear around 2,000 - 2,200 tied up, and 2,500 - 2,900 under way

Observations

1. With engine set to approx' 1000 - 1050rpm, engine starts as it should, does not stall when fwd is engaged (rpm drop by approx 100rpm in gear)
2. Engine speed has been checked with laser tacho.
3. Engine does not smoke including at WOT, in gear

Entire fuel system cleaned, exhaust elbow and back pressure checked, injectors and lift pump replaced and high pressure pump repaired.

Any advice or known common faults with the regulation system would be greatly appreciated!!
Thanks in advance, Dan
Click to expand...

One of the many makers settings on a diesel engine is the fuel volume limit. This limits the amount the fuel pump can overfuel in order to get ecceleration without overload and smoke . It looks like the setting on your engine may be incorrect and I would have thought a Volvo engineer would know where it was in order to correct this. On some of the older engines this was a wire locked screw near the governor which limited rack movement.


Mind you the same symptoms can be experienced by a common fault that develops in some of these engines where they are installed in yachts as replacements but not fitted with a high rise exhaust . This allows a small amount of water to flow back into number 3 cylinder every time the engine stops. This causes corrosion around the valves and bores with a drop in performance. This has happened to a couple of boats in our marina! This may not be your problem if it was apparent from day 1.
 
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Kylema 2 said:
I have replaced all rubber fuel lines, cleaned tank (Dreaded BUG!) filters etc.
I ran the engine from a separate tank direct to the lift pump just to be sure
Thanks to everyone for your input!
Click to expand...
VPMD engines come with a micro inline filter in the final banjo fitting onto the lift pump. Check if it is there, remove and lob over your shoulder. Item 4A in this exploded view.
 
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Engine problems

I too have a Perkins Perama M20 ( like the Volvo MD2020 ) and I had some very odd random revving and faltering problems -After all kinds of testing I assumed it was the governor/injector pump/ prop etc. But it was down to AIR. I too fed the injector pump with a separate fuel supply from a can and still had the symptoms. I eventually traced it to a minute leak in the unions to the secondary fuel filter(which was still in the circuit) I found the problem by putting the whole filter assembly in a bucket, pumping air into it and watching for bubbles! I replaced the pipes and banjo unions and been running fine ever since!
 
Bilgediver said:
One of the many makers settings on a diesel engine is the fuel volume limit. This limits the amount the fuel pump can overfuel in order to get ecceleration without overload and smoke . It looks like the setting on your engine may be incorrect and I would have thought a Volvo engineer would know where it was in order to correct this. On some of the older engines this was a wire locked screw near the governor which limited rack movement.
Click to expand...


It was mentioned, but was told its factory set and shouldn't need adjusting

Bilgediver said:
Mind you the same symptoms can be experienced by a common fault that develops in some of these engines where they are installed in yachts as replacements but not fitted with a high rise exhaust . This allows a small amount of water to flow back into number 3 cylinder every time the engine stops. This causes corrosion around the valves and bores with a drop in performance. This has happened to a couple of boats in our marina! This may not be your problem if it was apparent from day 1.
Click to expand...

Thanks, I'll bear that in mind, I did intend to do a compression test soon so that should pick that up (Volvo guy has agreed to lend me the equipment required to do this)
 
Has anyone fiddled with the factory set settings on the governor?
Or did you buy the boat with the engine running like this?
Has the engine ever run correctly in your ownership?
Have a look at my post regarding the problems I had with a Yanmar 1GM10, in particular this one:

http://www.ybw.com/forums/showthread.php?t=312212

Is there a possibility that your engine has something like this that may be causing your problems?
 
mickywillis said:
Has anyone fiddled with the factory set settings on the governor?
Or did you buy the boat with the engine running like this?
Has the engine ever run correctly in your ownership?
Have a look at my post regarding the problems I had with a Yanmar 1GM10, in particular this one:

http://www.ybw.com/forums/showthread.php?t=312212

Is there a possibility that your engine has something like this that may be causing your problems?
Click to expand...

The governor/max fuel delivery screw hasn't been touched since I've had it, can't say if previous owner has messed with it. it still has a cap on it.
Filters are the screw on type, so no elements to mess with.
engine has never run correctly, but has got slightly worse over time.
At first I adjusted the idle screw to counter stalling in gear at idle, which worked for a time. this left the screw was fully wound in.
 
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So from your reply, it would be safe to assume that you bought the boat with this problem?
Was this why the original owner was selling it?

I'm surprised that the VP engineer hasn't checked the engine compressions, probably one of the best tests you can carry out on a undiagnosed fault.
How easy/difficult is the engine to turn over by hand? If weak compression, you'll be able to turn the engine over fairly easily by hand on the flywheel or on a starting handle.
Has anyone checked the valve clearances? Also have the timing marks been checked for correct alignment? I'm assuming the diesel pump is driven by a gear off the main crankshaft?
If the injection pump has been removed at some time and then refitted in the incorrect position in relation to crank/piston positions, you could experience the problems mentioned.

When the engine does run, are there any unusual mechanical noises coming from the engine? Any knocking/metallic clunks, tapping (other than normal diesel engine knock)
Could the engine have been hydraulically locked up at some stage and the con rods bent, reducing compression and making more noise?
Clutching at straws, but if you haven't thought of the above issues, it may be worth checking.
 
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