Volvo penta d6 catastrophic fail at 200 hours - hole in piston - oil spilled in bilge

[Rgadala1]

HELP! HELP ! HELP!

I recently bought (august 2015) a Cruisers Yachts Cantius 48 with twin Volvo Penta 600 IPS. When I bought the boat i had my local (miami) Volvo dealer go out and perform an engine survey. All seemed to check out and after a full service performed by the Volvo Dealer in NY, i bought my boat and had the Volvo Mechanic, who is also a captain, bring the boat down from NY to Miami (about 4 days at sea) - after that we serviced the engines and drives again and i have been enjoying ever since.

During Memorial day weekend last month after going down to Islamorada (about 65 miles) and returning to Miami we headed out to Bimini (Bahamas) (90 miles) for another 5 days, where we mostly stayed at the marina. The day before returning to Miami i topped off fuel and went out for a day trip. Next day I headed back to Miami. Up to now all has been perfect... but then... as we were reaching Miami (4 miles out) my STBD engine lost power. I put engines on idea and tried to go again in hopes that it may have been something simple. As I tried to rev up the engine it was evident that it had no power, so i reversed hoping that i might have caught a line on the props. Then tried to go again and no power. I turned both engines off and opened the engine hatch.

and here we go... STBD engine oil was all over the bilge, so obviously i left engine off and returned home on my PORT engine only.

Volvo came out and basically said that my engine When Volvo came to diagnose they found several pistons with low or no compression. They opened up the engine and found that one of the piston heads had a hole on it. So im looking at a rebuild.

We had the engine pulled from the boat and Volvo has disassembled it and found 20 bent valves and an injector failure (in the open position).

Diagnosis: Not my fault, the timing gear slipped for no apparent reason and has caused all the damage.

I need help - this engine only has 210 hours and the boat cost me over $500k. I am now looking at a full rebuild and no idea of why this happened and if it can happen again or to my other engine.

Any feedback is appreciated.

 

[spannerman]

Sorry to hear about your bad luck, the D6 doesn't have timing gears in the normal sense. It has a gear driven from the crank which then drives a chain up to the camshafts, so the failure has two possibilities either the gear or the chain broke. I have never come across this failure yet in a D6 but there is always a first time, the chain sprockets are bolted to the cams so it could have come apart there, I think your other engine should be fine as in all the years I've been with Volvo I have never seen this failure. Seen plenty of injector faults and replaced dozens of them! I can only speculate that the blowby from the hole in the piston affected the lube system i.e. blew the oil out so the engine collapsed.

 

[Portofino]

Sorry to hear this too .
Oil pressure guage + oil temp guage ? --- any thing happen before the "power loss" ?
Where did the oil escape from , exactly which part /hole ?

Or other alarms ? Fuel line pressure issues at a injector ? to identify faulty injector before piston melts ?

It's a bit chicken and the egg which came 1st ?
Unlikely to be a timming gear failure 1st unless you thrashed it ? And /or you del skipper has too ? Previous to you getting it ? If it was you are very unlucky -I believe you make your own luck -----

That leaves Load -excess load is a boat diesel engine enemy .
Is your boat heavey ?
What rpm have been running at ?
How fast was cruise ?

Without a EGT guage you don,t really know how near you ( and previous skippers ) were to close to - damaging by overheat the valves /piston(s)
Exhaust Gas Temperature =EGT .

Thing is chicken + egg
Loss of oil -rapide overheat of the rings -loss of power rpm as they expand -fuelling stays high rpm drops -EGT risers valves
Melt -thermal stress become poor fitting tight -drops , piston hits some -valve gears teeth jump /snap .
But what alarmed off ?

Or Valve gear fails (unlucky ) in which case BANG and stop as valves hit piston s -but no overheat symptoms or oil spillage

We are back to load I,am afraid

 

[TQA]

Sounds to me like you had a valve head come off in one cylinder, the engine would keep running but at low power output and damage to the piston crown is certain.

The engine running with a holed piston would cause the oil to be blown out.

The damage in the combustion chamber then jammed the other valve in that chamber which stressed the whole valve train and something in the train slipped or jumped a tooth which bent the other valves when they hit their respective pistons. At this point the engine would normally stop of it's own accord.

But you say you stopped that engine so maybe the valve gear failure occurred when someone attempted to start it again. This is not unusual.

Did you cause it to fail by running at high speed for long periods ? A diesel sold for marine use is normally rated for continuous use at WOT. What does your manual say? I have come across identical engines with slightly higher RPM limits when sold as recreational use, commercial users get a lower setting on the governor because they often run longer at WOT. NB Bimini to Florida is not 'longer'!

 

[volvopaul]

Sounds to me like you had a valve head come off in one cylinder, the engine would keep running but at low power output and damage to the piston crown is certain.

The engine running with a holed piston would cause the oil to be blown out.

The damage in the combustion chamber then jammed the other valve in that chamber which stressed the whole valve train and something in the train slipped or jumped a tooth which bent the other valves when they hit their respective pistons. At this point the engine would normally stop of it's own accord.

But you say you stopped that engine so maybe the valve gear failure occurred when someone attempted to start it again. This is not unusual.

Did you cause it to fail by running at high speed for long periods ? A diesel sold for marine use is normally rated for continuous use at WOT. What does your manual say? I have come across identical engines with slightly higher RPM limits when sold as recreational use, commercial users get a lower setting on the governor because they often run longer at WOT. NB Bimini to Florida is not 'longer'!

As far as I'm aware no Volvo is rated for continuous use, Volvo state open to max throttle and reduce by 200 rpm , that is your continuous use rating.
Sound to me like an injector has seized causing the piston crown to fail hitting the valves and destroying the valve head which has jammed and snapped the chain.

 

[Portofino]

Here some clues ?
http://volvoforums.com/forum/penta-37/piston-problem-volvo-penta-d6-310a-16723/

 

[Trundlebug]

I'm surprised you didn't notice (at the very least) any excessive smoke before the ultimate failure.
There would have been early warning signs other than just loss of power, like smoke, rattling, coughing, noises, did you not see or hear anything unusual at all before it failed?

 

[TQA]

As far as I'm aware no Volvo is rated for continuous use, Volvo state open to max throttle and reduce by 200 rpm , that is your continuous use rating.
Sound to me like an injector has seized causing the piston crown to fail hitting the valves and destroying the valve head which has jammed and snapped the chain.

I am curious. Why would a seized injector cause piston crown failure? Is there some mechanical part that sticks out and clobbers the piston. I don't remember ever coming across an injector that would do that.

 

[Portofino]

Siezed , the sence stuck open ,spraying too much fuel in - it does not "clobber " anything .
Over fuelling
is a term loosely used for any condition during which too much fuel is injected for the amount of air available and normally results in black smoke and abnormally high EGT's.

The only type of "overfuelling" which can result in engine seizure without due up-front warning is when an injector or injectors fail catastrophically. This will normally produce cylinder washing as well as crown flaming (fuel lying on the piston crown burning with a slow, hot flame burning all lubrication off the cylinder liner ) This will induce piston skirt seizure (normally in the trust plane, 90 degrees to the gudgeon pin).
Depending on the metal can burn a hole in the crown = blowby ,Oil pipe gasket bursts = oil in the bilge
And /or burn the valve s = drop off /snap at the stem = clobber piston -and /or loose piece jamming a not knackered valve = shock force transmitted back to the timming gear = sprocket fracture / gear tooth snapped -which is what we have here .

The biggest cause of such sudden injector failure is presence of water - this causes the complete injector tip to fail resulting in a constant stream of diesel being pumped into the engine causing the results indicated above.

Also -excess water ( chicken / egg) causes spalling -this is where the hydrogen is released on breakdown of the water ,into microscopic cracks in the piston surface ,it starts to degrade the metal via a combination of direct combustion Of the metal and cavitation = leading to a hole

Filtration issue -Op Said he topped up in Bahamas before setting off .
WIF ? Water In Fuel -alarms are there any fitted ?
EGT - guages ? - ". " ". ". ". ?
What other error codes /alarms in the D6 set up re fuel pressure issues ?

Rumour has it batch of faulty Bosch tips ? --- nice cop out me thinks

It's either water getting through to the tips = inadequate filtration set up ?

Or in the absence of water ( explains why some failures have tested the tips and they were fine ) Overloading = excessive EGT = dropped valve (s)

 

[aquatom]

I've seen this happen 3 times now and in all cases there was a very neat hole cut into the piston crown. All 3 boats had been chipped to give extra hp.

 

[Latestarter1]

Siezed , the sence stuck open ,spraying too much fuel in - it does not "clobber " anything .
Over fuelling
is a term loosely used for any condition during which too much fuel is injected for the amount of air available and normally results in black smoke and abnormally high EGT's.

The only type of "overfuelling" which can result in engine seizure without due up-front warning is when an injector or injectors fail catastrophically. This will normally produce cylinder washing as well as crown flaming (fuel lying on the piston crown burning with a slow, hot flame burning all lubrication off the cylinder liner ) This will induce piston skirt seizure (normally in the trust plane, 90 degrees to the gudgeon pin).
Depending on the metal can burn a hole in the crown = blowby ,Oil pipe gasket bursts = oil in the bilge
And /or burn the valve s = drop off /snap at the stem = clobber piston -and /or loose piece jamming a not knackered valve = shock force transmitted back to the timming gear = sprocket fracture / gear tooth snapped -which is what we have here .

The biggest cause of such sudden injector failure is presence of water - this causes the complete injector tip to fail resulting in a constant stream of diesel being pumped into the engine causing the results indicated above.

Also -excess water ( chicken / egg) causes spalling -this is where the hydrogen is released on breakdown of the water ,into microscopic cracks in the piston surface ,it starts to degrade the metal via a combination of direct combustion Of the metal and cavitation = leading to a hole

Filtration issue -Op Said he topped up in Bahamas before setting off .
WIF ? Water In Fuel -alarms are there any fitted ?
EGT - guages ? - ". " ". ". ". ?
What other error codes /alarms in the D6 set up re fuel pressure issues ?

Rumour has it batch of faulty Bosch tips ? --- nice cop out me thinks

It's either water getting through to the tips = inadequate filtration set up ?

Or in the absence of water ( explains why some failures have tested the tips and they were fine ) Overloading = excessive EGT = dropped valve (s)

Voice of reason at last!

Water and common rail fuel injection is catastrophic, self induced by inadequate filtration practices.

Bosch DID have an issue with faulty common rail CRIN 1 injectors, same as D4/6 however IVECO copped for most of them and that was in 2002, nothing whatsoever since and CRIN 1 now replaced with CRIN 3.

 

[volvopaul]

I've seen this happen 3 times now and in all cases there was a very neat hole cut into the piston crown. All 3 boats had been chipped to give extra hp.

Whoever is selling chip mods to fit D series motor needs taking off the planet, dont they realise props move boats not engines

 

[superheat6k]

When looking at a catastrophic machine failure the investigation needs to try to work out what happened first, often a far from simple task.

Once metal debris starts flying the secondary damage can be very dramatic and extensive, but only by understanding the likely root cause or possible causes can the problem be understood, so preventing recurrent failure.

In this case was the hole in the piston a smashed hole, e.g. dropped valve head, or melted, e.g. over fueling / overloading.

If the camshaft was held by a jammed valve the slip would soon see the rest of the damage as the other pistons in turn clouted their valves and bent their rods. The extensive secondary failure could literally occur within a few revolutions, and indeed would have to as the engine would loose all power as soon as the slip occurred so only its momentum would remain.

In view of the damage a replacement engine might be the more effective option, certainly the crankshaft and camshaft have been subjected to forces never intended.

 

[Latestarter1]

When looking at a catastrophic machine failure the investigation needs to try to work out what happened first, often a far from simple task.

Once metal debris starts flying the secondary damage can be very dramatic and extensive, but only by understanding the likely root cause or possible causes can the problem be understood, so preventing recurrent failure.

In this case was the hole in the piston a smashed hole, e.g. dropped valve head, or melted, e.g. over fueling / overloading.

If the camshaft was held by a jammed valve the slip would soon see the rest of the damage as the other pistons in turn clouted their valves and bent their rods. The extensive secondary failure could literally occur within a few revolutions, and indeed would have to as the engine would loose all power as soon as the slip occurred so only its momentum would remain.

In view of the damage a replacement engine might be the more effective option, certainly the crankshaft and camshaft have been subjected to forces never intended.

Trevor, I agree with your comments absolutely regarding the importance of getting to the root cause of an an engine failure in order to prevent re-occurrence, however forensic failure analysis is extremely interesting and not over complex.

Having specialised in failure analysis on both slow speed and high speed diesel engines and at one was a warranty adjudicator of a major engine manufacturer following the path of a failure gives immense satisfaction.

Like many modern engines the Volvo D6 has no provision for repair, although parent bore there is no provision for an oversize piston, bore damage requires a new block, people in the U.S. have tried boring and fitting repair sleeves with only limited success and the very fact that a valve has been taken out means that head is scrap as well.

I would be interested to see the report from the V.P engineer who came to the conclusion that the gear had 'slipped', real dangerous territory that one, would have the manufacturing plant doing 100% inspection of crankshaft surface finish and if crank comes into the plant with already gear fitted I cold see plant inspectors descending on supplier auditing everything.

Chain drive on a medium duty diesel engine has certain benefits such as noise and cost, however is a poor compromise when it comes to durability, the bit that let down Gardner legendary durability.