Yanmar V Volvo

[Farmer Piles]

I suspect that this thread may divide opinion.
I have only been a member for about a year but I have noticed that I can only remember one Yanmar engine thread but there seems to be a continuous trickle about Volvo engine problems.
Is it a numbers game in that there are many times the number of Volvos out there compared with Yanmars? Or are they on the whole more prone to breakdown or the need for a higher level of maintenance and repair?
I do like Whys and Wherefores, it brings out the nerdy side of me. A bit like More or Less on Radio 4.

 

[Mr Googler]

Those with yanmar’s are too busy crying into their cornflakes after ordering a few parts ???

 

[ari]

There are WAY more boats with Volvo Penta than Yanmar, so yes, I'd say it's mostly a numbers game, although VP has had a few problem products, the original D3, the composite outdrive, etc. That said, many Yanmars were paired with Mercruiser Bravo outdrives, which I believe were known in the trade as 'grenades', although technically it was the Mercruiser legs that were grenading, rather than the Yanmar bits.

 

[Portofino]

It is a numbers game on one hand but inho Volvos are are theses days poorly engineered .
Initially in the 70 s with outdrives ( made of AL) they were fitted on small boats mainly used in lakes .
Even in Scandinavia they lifted them out in the winter and today the manuals still have a chapter on “ winterisation “ and dry storing etc .
So the corrosion protection for the bolt on bits was in there mind kinda covered by the usage patterns in the day .Same for the dangly outdrives , indeed whats dangly when it’s dry stored in a warm shed or sat on a boat lift outside a villa in Florida .

So today with bigger boats as the Hp increased and IPS developed to meet the extra Hp , boats are dunked year round .
The riser material , turbo exhaust flanges , elbows are still basically cast iron as per 70;s tech and rot away .
Even the sundry items bolted on have iron bolts which have a light blow of green paint .Looks great at a boat show but 3 years down the line the paint flakes off and rust appears .

Oily bits are oily so they are fine out of sight .

Further more in the power grabbing 90 s they came upon a cross roads re power .You can’ t argue with “ there is no substitute for cubes “ in terms of power and longevity.Volvo did ! They supercharged the 41 B block .
More belts , clutch , Y valves , flap , pipe work and extra ECU hassle squeezing more Hp out of 3.7 L .More to go wrong and fill up this forum .

A Yanmar none SC 6 L has gotta be a better option .

In terms of packaging the ECU is mounted on the engine = vibration + heat soak .
Also the strainer is over the alternator = it risks a wetting - not good .
The clue is the details .Like no rocker box gasket on the KAD 300 - urgh .

The later D series i understand have throw away blocks , no liners and the D3 sequential turbos , which stick if not used .


I suspect the 6 series Yanmar or any other series have been thought through by the Japanese carefully. Bit like there car engines. 15 yrs ago there was iirc a valve spring or something issue with a 6 series variant , a duff set from a duff supplier got out .This is history as there was a recall .

If you are contemplating ending up with a VP boat ( except the D12 which is from the road vehicles) then its gonna be a hands on relationship and you need to be mechanically minded , on top of them hands on .

You might like that .They do say 50 % of the enjoyment of owning a mobo boat is fixing things and the other 50 % sailing in it .

I had all the well documented VP woes with KAD 300s boat putting on 600 hrs .Risers , turbos , oil leaks rocker box , rusty fuel pipes , rusty pulleys , belts breaking at sea , rusty elbows , block spray heads on the elbow , leaky water pumps , dodgy temp reading = diagnosed as dodgy loom , various SC pipage leaks .

In the same hrs approx 600 over 6 seasons with MAN s I have only had one sensor let go , which was not a show stopper .
The paint does not flake off the expose bolts do not rust , the pulleys are made of marine environment suitable metals .
The one belt is massive , but the alternator is about the same size physically.
Each rocker box has a nice gasket , a duel metal + rubber affair that sits on a groove = can be reused even with zero leaks .Howzat for German engineering ?
The KKK turbos are miles away from seawater by design so aren’t silently corroding way .

The “numbers game ” masks the poor engineering on here .

Folks just seem to adopt a British stiff upper lip and grin and bear it …….living with a VP boat .

And I am not referring to outdrives or IPS , those woes are EXTRA on top .

 

[oceanfroggie]

Those with yanmar’s are too busy crying into their cornflakes after ordering a few parts ???

Yanmar engines are used in millions of Toyota land cruisers so parts are inexpensive relatively speaking.

 

[ari]

Yanmar engines are used in millions of Toyota land cruisers so parts are inexpensive relatively speaking.

I'm not an expert so stand to be corrected, but my understanding is that it's the other way around, Toyota don't fit Yanmar engines, certain models of Yanmar engines use Toyota blocks (4.2 litre straight 6 I think).

But many Yanmar engines do not use that block, plus there is more to a marine diesel than just the block.

 

[ctva]

Having only recently looked at a Volvo in a friends boat, the thing that struck me was the complexity and bespoke nature of the various components of the Volvo. Where a simple rubber pipe would do, the Volvo had a special molded and shaped 'thing' which cost a packet but more importantly could not be replaced without a Volvo part ordered from a main distributer. Both my boats have been Yanmar, simple agricultural, easily fixed and they just work.

I also don't like the green colour.

 

[petem]

It is a numbers game on one hand but inho Volvos are are theses days poorly engineered .
Initially in the 70 s with outdrives ( made of AL) they were fitted on small boats mainly used in lakes .
Even in Scandinavia they lifted them out in the winter and today the manuals still have a chapter on “ winterisation “ and dry storing etc .
So the corrosion protection for the bolt on bits was in there mind kinda covered by the usage patterns in the day .Same for the dangly outdrives , indeed whats dangly when it’s dry stored in a warm shed or sat on a boat lift outside a villa in Florida .

So today with bigger boats as the Hp increased and IPS developed to meet the extra Hp , boats are dunked year round .
The riser material , turbo exhaust flanges , elbows are still basically cast iron as per 70;s tech and rot away .
Even the sundry items bolted on have iron bolts which have a light blow of green paint .Looks great at a boat show but 3 years down the line the paint flakes off and rust appears .

Oily bits are oily so they are fine out of sight .

Further more in the power grabbing 90 s they came upon a cross roads re power .You can’ t argue with “ there is no substitute for cubes “ in terms of power and longevity.Volvo did ! They supercharged the 41 B block .
More belts , clutch , Y valves , flap , pipe work and extra ECU hassle squeezing more Hp out of 3.7 L .More to go wrong and fill up this forum .

A Yanmar none SC 6 L has gotta be a better option .

In terms of packaging the ECU is mounted on the engine = vibration + heat soak .
Also the strainer is over the alternator = it risks a wetting - not good .
The clue is the details .Like no rocker box gasket on the KAD 300 - urgh .

The later D series i understand have throw away blocks , no liners and the D3 sequential turbos , which stick if not used .


I suspect the 6 series Yanmar or any other series have been thought through by the Japanese carefully. Bit like there car engines. 15 yrs ago there was iirc a valve spring or something issue with a 6 series variant , a duff set from a duff supplier got out .This is history as there was a recall .

If you are contemplating ending up with a VP boat ( except the D12 which is from the road vehicles) then its gonna be a hands on relationship and you need to be mechanically minded , on top of them hands on .

You might like that .They do say 50 % of the enjoyment of owning a mobo boat is fixing things and the other 50 % sailing in it .

I had all the well documented VP woes with KAD 300s boat putting on 600 hrs .Risers , turbos , oil leaks rocker box , rusty fuel pipes , rusty pulleys , belts breaking at sea , rusty elbows , block spray heads on the elbow , leaky water pumps , dodgy temp reading = diagnosed as dodgy loom , various SC pipage leaks .

In the same hrs approx 600 over 6 seasons with MAN s I have only had one sensor let go , which was not a show stopper .
The paint does not flake off the expose bolts do not rust , the pulleys are made of marine environment suitable metals .
The one belt is massive , but the alternator is about the same size physically.
Each rocker box has a nice gasket , a duel metal + rubber affair that sits on a groove = can be reused even with zero leaks .Howzat for German engineering ?
The KKK turbos are miles away from seawater by design so aren’t silently corroding way .

The “numbers game ” masks the poor engineering on here .

Folks just seem to adopt a British stiff upper lip and grin and bear it …….living with a VP boat .

And I am not referring to outdrives or IPS , those woes are EXTRA on top .

Porto, do you have any evidence that heat is a cause of ECU failure?

 

[petem]

It wouldn't surprise me if Volvo outsold Mercruiser 100 to 1 in the UK so you're bound to hear more stories of 'green' issues.

The ubiquitous AD/KAD series of engines are also relatively easy to repair and find parts for so people often get good advice from asking questions.

It maybe that Mercruiser engines are more reliable but if you get a problem with one then there's far less knowledge out there to help you. And due to lack of scale, less pattern parts.

 

[Hambleite]

Gotta love this thread:

Q - What's best - Volvo vs Yanmar?
A - MAN

On the basis that the question refers to VP and Yanmar, that would imply that the interest level is with boats in the 30ft to 40ft range. I'm pretty sure that zero MANSs were fitted to boats in that range and therefore a somewhat 'left field' answer!

However, I do also believe that large CC, unstressed engines are the way to go, it's just this wasn't (and therefore isn't) an option on a lot of boats.

 

[Portofino]

Porto, do you have any evidence that heat is a cause of ECU failure?

Indirectly due to insulation of the loom deterioration, the heat soak effect over many cycles and of course years .
In my boat my French tech told me he was seeing a lot of spurious symptoms, which resulted in a parts throwing fest at the engine before the loom / ECU issues were diagnosed. A rare honest guy .

It comes up on here a few times = “ pull the plug and clean the ver d gris of the connectors “ = sometimes you get lucky , sometimes you don’t.
They should be mounted separately in a weather proof box remote from the engine and connected via an umbilical .
That s what they do in the auto industry, place the ECU somewhere dry , damp free and vibration free and un susceptible to heat soak cycles .

In marine those unbiblical s need to be up to the job with rubber gaskets and sufficient sized brass ( or what ever metal ) pins
So’s not to deteriorate and start sending spurious voltages around the shop .

Further more resorting to potting compound is a nightmare as eventually it deteriorates .Talking decades but my old KADS will be coming up to 20 yrs .

If I went down the car auctions today in search of a 95 Lexus LS 400 I don’t think the ECUs will be sat on top of the engine .
Nope mounted remotely behind a bulkhead ……crucially the engine still works and despite any high milage issues I would have confidence to drive away with it = only worth a few hundred quid in the ring ,
Not thousands btw .

As I said the Japanese and from experience in marine the Germans just think things out from basic engineering .

I mean take an alternator , no one makes there own they buy off the shelf from Bosch , Denso , Merelli etc .
Why place it where it risks a soaking every time the strainer is checked ?
Then why on Earth choose a cast iron pulley that corrodes in a marine environment? The others choose a none ferrous metal more suitable for sea salty air .Same with the bolts and studs.

 

[Portofino]

Gotta love this thread:

Q - What's best - Volvo vs Yanmar?
A - MAN

On the basis that the question refers to VP and Yanmar, that would imply that the interest level is with boats in the 30ft to 40ft range. I'm pretty sure that zero MANSs were fitted to boats in that range and therefore a somewhat 'left field' answer!

However, I do also believe that large CC, unstressed engines are the way to go, it's just this wasn't (and therefore isn't) an option on a lot of boats.

Wrong conclusion, just relaying experience.
Pretty sure Yanmar are built in a Japanese mindset .I had a 1 GM in a sail boat many moons ago but it’s tiny .
Btw I have a Yanmar powered geny which like my 1 GM I have spent zero on bills excluding oil / filters / and one belt .
Its paint is not peeling and it’s bolts not rusting , even got a S Steel exhaust manifold .

As far as 30-40 ft range there are the Pershing 37 with CAT 3208 ‘ s V8 s old school CATs or newer Yanmar 480s straight 6 litre .
Itama 38s older with a range inc CATs and the newer 40 with MAN the smallest 8.3 L and lately Cummins 450-550 hps .
Also if you care to stroll around genoa plenty of other small boats without Volvos , Nanni etc .Baia used to do none Volvo boats the B 1 etc .
You can get Yanmar Baia 43s and even Yanmar Superhawk 43 s as well , come with Arnesons.But a better prospect than outdrives going fwds …..literally.

Take this brand Eg Positano .
Shafts as well ,

 

[petem]

Indirectly due to insulation of the loom deterioration, the heat soak effect over many cycles and of course years .
In my boat my French tech told me he was seeing a lot of spurious symptoms, which resulted in a parts throwing fest at the engine before the loom / ECU issues were diagnosed. A rare honest guy .

It comes up on here a few times = “ pull the plug and clean the ver d gris of the connectors “ = sometimes you get lucky , sometimes you don’t.
They should be mounted separately in a weather proof box remote from the engine and connected via an umbilical .
That s what they do in the auto industry, place the ECU somewhere dry , damp free and vibration free and un susceptible to heat soak cycles .

In marine those unbiblical s need to be up to the job with rubber gaskets and sufficient sized brass ( or what ever metal ) pins
So’s not to deteriorate and start sending spurious voltages around the shop .

Further more resorting to potting compound is a nightmare as eventually it deteriorates .Talking decades but my old KADS will be coming up to 20 yrs .

If I went down the car auctions today in search of a 95 Lexus LS 400 I don’t think the ECUs will be sat on top of the engine .
Nope mounted remotely behind a bulkhead ……crucially the engine still works and despite any high milage issues I would have confidence to drive away with it = only worth a few hundred quid in the ring ,
Not thousands btw .

As I said the Japanese and from experience in marine the Germans just think things out from basic engineering .

I mean take an alternator , no one makes there own they buy off the shelf from Bosch , Denso , Merelli etc .
Why place it where it risks a soaking every time the strainer is checked ?
Then why on Earth choose a cast iron pulley that corrodes in a marine environment? The others choose a none ferrous metal more suitable for sea salty air .Same with the bolts and studs.

That'll be a 'no' then. I do recall someone saying that the ECU is attached to the fuel filter to get some cooling from the fuel. I'm not sure if it's true or not.

 

[julians]

just want to debunk a few of these statements below that appear as absolutes (in red in the quote below) - I think the general thrust of it that volvos are not as well engineered as they could be probably has some truth to it, But some of these statements phrased as black and white are not correct. I've never owned a yanmar engine , so I cant really compare the two. I think you probably have to look at each specific engine versus the other engine, dont think you can just compare at a brand level. I'm no volvo fanboy, but to be fair to the volvo engine in my boat, its been fine on the whole.

It is a numbers game on one hand but inho Volvos are are theses days poorly engineered .
Initially in the 70 s with outdrives ( made of AL) they were fitted on small boats mainly used in lakes .
Even in Scandinavia they lifted them out in the winter and today the manuals still have a chapter on “ winterisation “ and dry storing etc .
So the corrosion protection for the bolt on bits was in there mind kinda covered by the usage patterns in the day .Same for the dangly outdrives , indeed whats dangly when it’s dry stored in a warm shed or sat on a boat lift outside a villa in Florida .

So today with bigger boats as the Hp increased and IPS developed to meet the extra Hp , boats are dunked year round .
The riser material , turbo exhaust flanges , elbows are still basically cast iron as per 70;s tech and rot away . I have a windy 25 with a d4 engine and dph outdrive, its been in the salt water pretty much 365 days per year since 2007. The exhaust elbow rotted this year, I dont think 14 years is too bad a lifespan for an elbow on any engine. and the drive itself has been fine in terms of corrosion - ie no sign of any corrosion issues.
Even the sundry items bolted on have iron bolts which have a light blow of green paint .Looks great at a boat show but 3 years down the line the paint flakes off and rust appears . No idea what my bolts are made off , but they havnt rusted

Oily bits are oily so they are fine out of sight .

Further more in the power grabbing 90 s they came upon a cross roads re power .You can’ t argue with “ there is no substitute for cubes “ in terms of power and longevity.Volvo did ! They supercharged the 41 B block .
More belts , clutch , Y valves , flap , pipe work and extra ECU hassle squeezing more Hp out of 3.7 L .More to go wrong and fill up this forum .

A Yanmar none SC 6 L has gotta be a better option .

In terms of packaging the ECU is mounted on the engine = vibration + heat soak . Not with the D4, ecu mounted on boat bulk head - dont think you can just make blanket statements like this without caveats
Also the strainer is over the alternator = it risks a wetting - not good . Not with the d series, again blanket incorrect statements
The clue is the details .Like no rocker box gasket on the KAD 300 - urgh .

The later D series i understand have throw away blocks , no liners and the D3 sequential turbos , which stick if not used .


I suspect the 6 series Yanmar or any other series have been thought through by the Japanese carefully. Bit like there car engines. 15 yrs ago there was iirc a valve spring or something issue with a 6 series variant , a duff set from a duff supplier got out .This is history as there was a recall .

If you are contemplating ending up with a VP boat ( except the D12 which is from the road vehicles) then its gonna be a hands on relationship and you need to be mechanically minded , on top of them hands on .

You might like that .They do say 50 % of the enjoyment of owning a mobo boat is fixing things and the other 50 % sailing in it .

I had all the well documented VP woes with KAD 300s boat putting on 600 hrs .Risers , turbos , oil leaks rocker box , rusty fuel pipes , rusty pulleys , belts breaking at sea , rusty elbows , block spray heads on the elbow , leaky water pumps , dodgy temp reading = diagnosed as dodgy loom , various SC pipage leaks .

In the same hrs approx 600 over 6 seasons with MAN s I have only had one sensor let go , which was not a show stopper .
The paint does not flake off the expose bolts do not rust , the pulleys are made of marine environment suitable metals .
The one belt is massive , but the alternator is about the same size physically.
Each rocker box has a nice gasket , a duel metal + rubber affair that sits on a groove = can be reused even with zero leaks .Howzat for German engineering ?
The KKK turbos are miles away from seawater by design so aren’t silently corroding way .

The “numbers game ” masks the poor engineering on here .

Folks just seem to adopt a British stiff upper lip and grin and bear it …….living with a VP boat .

And I am not referring to outdrives or IPS , those woes are EXTRA on top .

 

[Portofino]

That'll be a 'no' then. I do recall someone saying that the ECU is attached to the fuel filter to get some cooling from the fuel. I'm not sure if it's true or not.

It’s a madness position from 1 st principals Pete .Will and does bite customers on the arse .
Its a Yes surly by the amount failing compared to other brands who engineered it out .

 

[petem]

just want to debunk a few of these statements below that appear as absolutes (in red in the quote below) - I think the general thrust of it that volvos are not as well engineered as they could be probably has some truth to it, But some of these statements phrased as black and white are not correct. I've never owned a yanmar engine , so I cant really compare the two. I think you probably have to look at each specific engine versus the other engine, dont think you can just compare at a brand level. I'm no volvo fanboy, but to be fair to the volvo engine in my boat, its been fine on the whole.

You're wasting your breath Julian.

It's also worth noting that ECU's fail on all kinds of vehicles and appliances.

 

[Portofino]

just want to debunk a few of these statements below that appear as absolutes (in red in the quote below) - I think the general thrust of it that volvos are not as well engineered as they could be probably has some truth to it, But some of these statements phrased as black and white are not correct. I've never owned a yanmar engine , so I cant really compare the two. I think you probably have to look at each specific engine versus the other engine, dont think you can just compare at a brand level. I'm no volvo fanboy, but to be fair to the volvo engine in my boat, its been fine on the whole.

Great to hear they are learning ……eventually.

 

[petem]

It’s a madness position from 1 st principals Pete .Will and does bite customers on the arse .
Its a Yes surly by the amount failing compared to other brands who engineered it out .

Do you have any statistics of failed ECU's by brand?

 

[Portofino]

The Ops asking for whys and wherefores .

Not just - buy a Yanmar .

 

[petem]

The Ops asking for whys and wherefores .

Not just - buy a Yanmar .

That'll be another 'No' then'. So to summarise....

You don't have any proof that heat is a contributing factor to ECU failure. And you don't have any proof that KAD ECU's fail any more frequently than those of other brands.