Volvo D series failures

[MapisM]

I have to disagree with Volvopaul regarding is comments regarding lack of displacement.

Fairenuff, but could you explain us what do they know exactly at VP that allows them to sell 80hp/liter engines for streamline production boats, whilst no other competitor goes much above 60hp/liter? I really don't think that Cat, Deere, MTU and so forth have so much to learn from VP in terms of "robust nature of the base motor components".

And these days, it doesn't take rocket science to squeeze more power from an engine, either.
Seatek builds diesels approaching 100hp/liter, but at least they have the common sense to recommend them for offshore boats.
And even the 80hp/liter (same as the D6-435!) of the same block, is still classified as a high performance engine, with a suggested 1000 hours TBO. It takes the 60hp/liter version to get a sensible 3000 h. TBO.
And mind, we're talking of a block whose reliability has been proven by many military boat applications, in various Countries.

 

[ulyden]

Fairenuff, but could you explain us what do they know exactly at VP that allows them to sell 80hp/liter engines for streamline production boats, whilst no other competitor goes much above 60hp/liter? I really don't think that Cat, Deere, MTU and so forth have so much to learn from VP in terms of "robust nature of the base motor components".

While MTU sell 60hp per liter of fast passenger (20000series) boats even they offer 70hp/l to pleasure craft.

Remember that volvo has sold 286hp from 3.6 liter kad 300 for a long time (10yers) without major problems.

While D6 435hp has a cylinder performance at 79hp per liter, it has only 60hp per liter of continuous [/COLOR]power. (10% speed reduction is about 75% engine power (2.5 curve)). KAD 300 had a continuous power on 254hk or 70hp per liter! Volvo claimed only 200rpm speed reduction on these! This represents approximately 89% engine power!

Not before a 510hp version of the D6 will have similar continuous-liter performance as the old kad300 engine! Let us hope that the world moves forward!

Expected life time is 5000hours for the D6. That means 500h full power and 4500h 75% power. If you use it 300h pr year you have the engine 16 years.

Its not possible to buy bigger pistons or new liners the engine block have to be replased!

 

[MapisM]

Mmmm... If your reply was addressed to my question "what do they know exactly at VP...", well, I'm still missing the answer.

Besides, what has the continuous power to see with what we were discussing?
Btw, according to what you're saying, if you keep a D6 at 90% of its max RPM, you can use it as a 320HP continuous unrestricted engine.
Now, I really don't think so.
In fact, aside from the fact that even VP class ANY version of the D6 block as rating 4/5 (which already says it all, really), it takes not less than the D12 to get a 300hp (not even 320!) proper rating 1 engine (at 25hp/liter!).

The point is, the only honest answer to my question above would be that what they actually know is that there's a market demand for engines like the D6-435, and decided to fullfill it, whilst other builders didn't.
Which is ok, as long as they (or you, or anyone else for that matter) don't pretend to convince us that Volvopaul statement was wrong.

 

[spannerman]

Interressting!
To bend this conrod its nessasary with 900bars. This is not possible by combustion! Did they explain?

This happened not because of cylinder overpressure, but because the excess of diesel from the damaged injector washed the oil off the bores and the piston seized at high rpm, this will throw the rod out of most engines.
I saw the engine in the shop and it wasn't pretty.
We also had two D 6 engines that dumped all their oil in the bilges because of overpressure in the sump, this wasn't noticed by the owners until red light came on and the engine shut down but by then it was too late the engines were beyond saving.

 

[ulyden]

Mmmm... If your reply was addressed to my question "what do they know exactly at VP...", well, I'm still missing the answer.

Besides, what has the continuous power to see with what we were discussing?
Btw, according to what you're saying, if you keep a D6 at 90% of its max RPM, you can use it as a 320HP continuous unrestricted engine.
Now, I really don't think so.
In fact, aside from the fact that even VP class ANY version of the D6 block as rating 4/5 (which already says it all, really), it takes not less than the D12 to get a 300hp (not even 320!) proper rating 1 engine (at 25hp/liter!).

The point is, the only honest answer to my question above would be that what they actually know is that there's a market demand for engines like the D6-435, and decided to fullfill it, whilst other builders didn't.
Which is ok, as long as they (or you, or anyone else for that matter) don't pretend to convince us that Volvopaul statement was wrong.

My only opinion of these new engines is "Ive seen it coming for a long time" as they are tested at the factory on clean road spec fuel I also think 435 hp is too much for the design and block capacity. Enough said .....


Point is! Volvopaul says 435hp is to much for this block!

Volvo has experience with this high power for the KAD300 engines fore over 10years!

Is the new engine weaker than the old? Strange!

Continues rating. Volvo says. 75% of full load continues power but only for 300h? pr year!

That means if you exceed 600h after 2 years you are out of warranty!

If you buy an engine for unrestricted use, you can use it at full power 24h a day!

3000h TBO means nearly 3 overhauls pr year if you do that!

I work with such engines! Normal TBO is 25-30 000h with full load! That means overhaul every 3 or 4 years with 8600h pr year! Cylinder power is down to 20-25hp/liter

This is meaningless for pleasure boats!

You also have to remember that if you compare engines litre power is not a good measure.

If you multiply brake mean effective pressure in bar with the piston speed in m/s you will find most of the engines operating in 200 area! A D6 has a BMEP of 20 and a piston speed of 12.7m/s 254 bar m/s

A KAD300 have 18.4bar bmep and 12m/s piston speed or 220bar m/s

The engines I work with has 26bar and 10m/s or 260bar m/s But this is continues rating!

The litre power is 25hp

That means that you can’t compare litre power with bigger engines!

If the big engines in the container ships( B&W or Sulzer) should have 60hp pr litre the power had been up to 12times higher than today! (5hp/liter)

Volvo sells these engines to the pleasure marked. 300h/year is enough! The warranty period is 600hours and most owners are pleased! They don’t offer these ratings as base load!

Fiat have the same A1 rating 300h pr year! Full throttle 10% of the time 90% engine speed rest! If you go to B rating you can run the engine 1500h pr year! Then the power is 10% lower! The numbers is from Fiat N60 370hp version!

The question is : Why is these engines braking down in Norway? Even the D6 310hp version are failing. Strange thing is that the D6 435 and D4 300 have not been troubling with this failure!

 

[ulyden]

Interressting!
To bend this conrod its nessasary with 900bars. This is not possible by combustion! Did they explain?

This happened not because of cylinder overpressure, but because the excess of diesel from the damaged injector washed the oil off the bores and the piston seized at high rpm, this will throw the rod out of most engines.
I saw the engine in the shop and it wasn't pretty.
.

The picture I showed was from a damaged engine! Problem is if you have a seizer the force is highest at max piston speed! Problem at max piston speed the crank is 90 deg on the crank shaft! A 900bar cylinder pressure would give a torque of 40Kn or 40times the normal torque!

(900kg/cm^2 *10.3cm^2*3.14/4=74990kg =Force. 0.055m is the arm! Torque is then 74990kg*0.055m= 4124kgm or 40 461Nm)


Then the engine stops instant and the crankshaft brakes if it has not 40times over capacity in torque!!

The friction power should heat the piston quite rapidly! The power is speed multiplied by force sp at 90deg atdc the speed is 26m/s and the force is 750KN. This is 20 000KW or 20MW power! This is unthinkable when you look at the picture of the piston! 20MW is heating up a 103mm bore piston quite rapidly!

Most of the engines caped running after this event! Stopping on cooling water fault or stopped by the owner! The owners only felt a knoking sound of the engine black smoke and bilge pump alarm!

So I don’t thick Volvo is telling You the truth!

 

[spannerman]

Whatever... I don't think most of us are really too interested in piston vmax, the fact is the engines used to fail and now they don't, so whether its water in the fuel, bad norwegian diesel on the west coast or because the wind was out of the east who cares. They seem to have nailed the problem and thats what most owners are interested in.
All I know is that the tiny ball in the injector that looked like the surface of the moon after water contamination and caused the injector to misfire now survives and we haven't had one failure since and we live in the failure hotspot on the westcoast of norway.
So I think owners of D4 and D6 engines can sleep better at night. I will try to find out at what serial number the new injector was introduced so owners can check what engine they have.

 

[DAKA]

Do you know if Volvo Penta recalled all the east coasters with original engines and replaced 4/6 injectors, even if out of warranty you would think this constitutes a design fault and repairs following sheered crank shaft/con rod could be touch and go engine write off.

Do you think UK boaters will need to consider taking an injector out to view the ball bearing as a precaution during annual maintenance, new injectors will be expensive but not as bad as a new engine.

 

[ulyden]

Whatever... I don't think most of us are really too interested in piston vmax, the fact is the engines used to fail and now they don't, so whether its water in the fuel, bad norwegian diesel on the west coast or because the wind was out of the east who cares. They seem to have nailed the problem and thats what most owners are interested in.
All I know is that the tiny ball in the injector that looked like the surface of the moon after water contamination and caused the injector to misfire now survives and we haven't had one failure since and we live in the failure hotspot on the westcoast of norway.
So I think owners of D4 and D6 engines can sleep better at night. I will try to find out at what serial number the new injector was introduced so owners can check what engine they have.

Yes I am starting to understand that simple logic and mathematics does not fit in here!

Volvo should at least tell the penta owners that they can relay their engines also on the west coast!

 

[Ronde]

Hi,
I am new to this forum and would like some help

It seems that i have now this same problem with injectors. I have a volvo penta D6 310-a Without any notice my starboard engine blew. The VP service will take the engine out next week and I will got more details after that. But all the symptoms refer to a melted piston (s) and a injector problem..

I talked with the previous owner of the boat and back in 2007 the same motor had a total breakdown. He was not 100% shure and VP-service never told the exact reason for the breakdown. But they thought it was the injectors. But anyway they changed the block, head, injectors etc. The engine was tested in dyno and everything was ok. The engine has been maintained every year By VP. After this the engine has done little bit more then 230 hours. And now again....

The rebuilt was 39K€ and it lasted for 230 hours. I would rather not spend 40K€ for 230 hours....

So my question how did VP solve this was it the injectors?. Did you have any more problems after you had it rebuilt? Did Volvo have any comments to this?



What seems strange is that the port engine has never had a problem but this has happened 2 times to the starboard engine???? So it can´t be the diesel...

 

[aquapower]

Hi,
I am new to this forum and would like some help

It seems that i have now this same problem with injectors. I have a volvo penta D6 310-a Without any notice my starboard engine blew. The VP service will take the engine out next week and I will got more details after that. But all the symptoms refer to a melted piston (s) and a injector problem..

I talked with the previous owner of the boat and back in 2007 the same motor had a total breakdown. He was not 100% shure and VP-service never told the exact reason for the breakdown. But they thought it was the injectors. But anyway they changed the block, head, injectors etc. The engine was tested in dyno and everything was ok. The engine has been maintained every year By VP. After this the engine has done little bit more then 230 hours. And now again....

The rebuilt was 39K€ and it lasted for 230 hours. I would rather not spend 40K€ for 230 hours....

So my question how did VP solve this was it the injectors?. Did you have any more problems after you had it rebuilt? Did Volvo have any comments to this?



What seems strange is that the port engine has never had a problem but this has happened 2 times to the starboard engine???? So it can´t be the diesel...

I would be checking for an installation fault, unles you are very unlucky I wouldn't expect this twice.

 

[Ronde]

The problem is that it´s now att the same service shop where it was built the last time... So I don´t think they will step up and say they did something wrong the last time....

 

[Latestarter1]

The problem is that it´s now att the same service shop where it was built the last time... So I don´t think they will step up and say they did something wrong the last time....

Suggest you re-read aqapowers note, suggested installation NOT the base engine should be checked.

Long time ago now, however Spannerman posted link to pictures of failed D6 engine which if I remember correctly had pressurised coolant via split copper injector sleeve.

We do not know exactly what your failure mode is from your original post, however we can only assume engine failed due to injector 'hosing' i.e. injector stays open washing lube oil off the bores leading to catastrophic piston pick up.

Bosch common rail injectors of the type used in your engines have excellent reliability/durability track record across a number of manufacturers not just Volvo and if your failure mode IS due to injector 'hosing' there can only be one cause which is contaminated fuel, generally water.

I would be having fuel samples from main tanks primary and 'last chance' on engine filter independently lab tested.

If you post pictures here of your filtration set up that would be helpful. Comments made here by VP people would suggest that Volvo is poor at policing new production installations and returning to aquapower's comment I would also agree that your engine may be victim of its operating environment.

Volvo do not help themselves putting the WIF sensor on the 'last chance' filter, I would refer to this as more of a 'too late' sensor. I also have an issue with Bosch core software which cannot detect a stuck open injector. I know that Cummins patented the 'Unintended fueling algorithm' for common rail systems, however Bosch were talking about developing their own system over ten years ago, looks like somebody has gone to sleep.

 

[spannerman]

This would appear to be true, however VP do give very specific filtration specs in their installation manual, its just that boat manufacturers fit whatever water separator filters they feel like, over which Volvo has no control. Hydrolift don't even fit a water separator on their boats the engine filter is the only one in the system!

 

[Ronde]

I will try to take pictures of the instalation for you... I´m not professional but what i can´t understand is why the other motor has been ok, all the time... It has old injectors and it uses the same tank.. And its running like a clock... And this happends the second time to the other one...