Yanmar 315HP 6LPA STP

Thank you for your interest. The original engines were twin 290 H.P. General Motors Detroit 8V 53N, 4 valve heads, High Speed diesels 2,800 rpm. After 38 years I sold them to a boat builder in Liverpool. He intended to install them in a new boat. You could say built to last but expensive to run. Based on my Yanmar experience to date they were relatively cheap!! I will get back to you on the points you raise in the morning. I hope my old Yanmar engine serves you well!
 
CliffordGuernsey said:
Thank you for your interest. The original engines were twin 290 H.P. General Motors Detroit 8V 53N, 4 valve heads, High Speed diesels 2,800 rpm. After 38 years I sold them to a boat builder in Liverpool. He intended to install them in a new boat. You could say built to last but expensive to run. Based on my Yanmar experience to date they were relatively cheap!! I will get back to you on the points you raise in the morning. I hope my old Yanmar engine serves you well!
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No I didn't buy it I know where there of a few 6lps , 2800 rpm is about right for an older heavy boat where your yanmars are much higher.
 
volvopaul said:
As the motors were supplied by an eu country I'm sure you should be covered by eu law and the 6 year warranty that so many people don't ask about when parts fail prematurely, I recently helped a Volvo owner with a 4 year old targa get new steering rams and a pump due to water ingress in the whole system. So I'm sure your legal team will be on the facts over this one.
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Many people misunderstand warranty, which is a contract between two parties and fail to acknowledge owners responsibilities.

Running contaminated fuel through your engine is akin to purchasing a new car kerbing the front wheel then expecting to claim under warranty.

If a manufacturer becomes aware of a product problem for example Volvo steering rams, normal that you set up an account in which you accrue policy payments which eventually become loaded on to the manufacturing cost of an engine or product. For example Yanmar set aside several million $$ to cover policy settlements on the 6LP valve issue which included additional warranty packages to re-assure the customer base.

On the basis of the evidence not sure why the Yanmar distributor paid for the first failure, either they had some of the accual money left in the valve failure pot OR they are less than sqeaky clean.

In paying for the first engine failure without establishing the root cause cause one could argue that the Distributor even contributed to the second failure, or as Spannerman pointed out yet another failure. Paying for the first engine has certainly not left them with a satisfied customer and may have left them with a soft underbelly, however OP is being misled by his experts and just like the Light Brigade charging the wrong guns at the moment.

Just wait until this outfit starts selling Mercruiser diesel engines all over again!
 
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The angle of the boat is not an issue as she gets up on the plane at about 12knots and the trim tabs keep her fairly level. You ask about the filters.The actual units are 38 cm high and 14 cm diameter. I cannot see a maker reference. The filters themselves are 11cm diameter and 12cm high. They were Micron 30 giving 2040pm when both engines failed. We put in 5 Micron with the new engine and these have not been a problem. I have worked out that the current filters have done 350 miles (say 30 running hours) and still look OK. I have been recommended to put in 10 Micron for next season. How does this sound to you? The internal diameter of the fuel pipe is about 1 cm.
You mention the engine was supplied by an EU country. This is true of Barrus but Guernsey is outside the EU and does not have a Sales of Goods Act. This does not of course mean I have no legal case here.
 
6LPA Problems

Reading over this thread, I have failed to find anything posted as to actual engine loading. This where I think we need to focus.

1) Has our poster verified maximum RPM that could be reached with the vessel equipped & fueled as he uses it?

2) Has our poster verified cruise RPM's under the same conditions?

3) Has our posted verified pyrometer temperature and boost readings at his cruise and WOT RPM's to see if they are within Yanmar specification and not being exceeded?

4) Does our poster even KNOW the MINIMUM RPM Yanmar requires these engines be able to reach under actual operating conditions?

5) And, has our poster verified true RPM on these non-adjustable Yanmar tachometers that are known to be inaccurate.

Maybe our poster can answer the above quires and eliminate my suspicions listed below without dwelling on other aspects. Just a few simple questions, please..



Seems that all is centered on a VE fuel pump issue and in all my years of driving diesels on the road ( millions of miles) , I just cannot link a possible VE pump issue to a dropped valve in an automotive diesel that has been "hot-rodded" to over 70 Horsepower per liter..

My money is split between two separate and non-related issues--Overloading and contaminated fuel and must be looked at 100% separate issues.

The only common denominator I see is the ignorance of the operator willing to accept "hog-wash" input by so called experts and then feed that to the insurance companies and lawyers.

And last........ I think this needs to be put into perspective. This repower replaced 8-53 Detroit's rated at around 280HP at 2800 RPM. The vessel went from approx 8 liters of iron per engine (maybe 3000 lbs) making a maximum of 35 HP per liter to a light weight automotive diesel with 1/3 as much iron rated at twice the HP per liter, and one that needs to see an honest 3950- 4000 RPM at WOT under working conditions and will not tolerate overloading in anyway shape of form. Remember the 8-53 was very forgiving as to over loadings as any "NA" Detroit is. Do you think we could be looking a some the common denominator here?? Seems to me we have a awful lot of boat here and not enough engine.



Fishing Fool
 
Not sure I like to be described as ignorant! You clearly have strongly expressed views and may well be correct but relying upon experts opinion should not be regarded as an ignorant thing to do. Misguided maybe! That aside I will attempt to reply to your questions.
1. Maximum revs when fully loaded is I think a bit around 3950. I will have to check when out tomorrow.
2. We cruise at 3300/3400 and get some 17 knots
3. No I have not. I have assumed that sea trials would have verified these were correct.
4. It is my understanding the WOT should be within 3950 and 4050. On sea trials it was certainly 3950 or possibly higher. She was light and recently anti fouled.
5. I do not think it unreasonable that I assumed the tachometers are accurate. Why would I assume otherwise. Now I know this of course raises other issues.
 
Strong Views

Clifford,

Yes, I do have strong views.

As to ignorant--I fall into this too..

g·no·rant/ˈignərənt/
Adjective:


Lacking knowledge, information, or awareness about something in particular: "ignorant of astronomy".




I consider myself as such in most subjects, but not this one.
 
Verification of Data

Clifford,

Spend some time and effort and eliminate my concerns:

1) Get yourself a photo tach. Very inexpensive in this country ( under $50 USD) . Test your tachs at the dock in neutral at 3400-3500 RPM steady state, engine warm.. Do it 2-3 times.. Then BUMP WOT, no load, and take a quick reading, or two.. Actual should be right at 4200 +/- 25-ish. Write all down and then compare your tachs to the actual.. Good time & $$ spent and would certainly make me eat some humble pie. That has shown me more than once it's good for my diet.

2) Get yourself a pair of pyrometers and boost gauges get them installed & working.. Search around the web site, "boatdiesel.com", for some suggestions on who is happy with what. At 70 hp+ / liter and wanting to use it all would certainly make that part of your "due diligence" as an operator.

3) Don't know much about the fuel over there, but here, using the USA blend of ULSD does not cause VE pump issues.. You might consider reading up on upgrading your fuel delivery system to insure that contamination was not the base issue of the pump and / or injectors... That fuel system will not tolerate even the most miniscule about of free or dissolved water. Remember, their is much more to fuel filtration than a Racor when dealing in this environment.


Fishing Fool
 
Thank you for this advice. I will follow up on it. I do hope the engines are OK for the boat as she is a very fine classic. Only two owners in 44 years. I have just spent £38,000 having her re-painted in Awlgrip, replacing the foredeck and fitting a bow thruster. Not sure I can attach a picture but will try.
 
In my opinion the installation ticklist should have been carried out to yanmars specs for warranty, if they have not been carried out then the supplying dealer is to blame.

Id agree with fishing fool ref the choice of engines, they would certainly not have been my first choice.

Fishing fool. is he the usa version of our latestarter?, or chief bod at yanmar usa.
 
CliffordGuernsey said:
I have checked and I can confirm that the tick list was done at sea trials and everything was O.K.
Click to expand...

So whats your thoughts over the failure then, do you think someone is not telling you the truth as both motors have failed in the same installation? there must be common ground somewhere as to the reason of failure.
 
volvopaul said:
In my opinion the installation ticklist should have been carried out to yanmars specs for warranty, if they have not been carried out then the supplying dealer is to blame.

Id agree with fishing fool ref the choice of engines, they would certainly not have been my first choice.

Fishing fool. is he the usa version of our latestarter?, or chief bod at yanmar usa.
Click to expand...

Fishing Fool pops up on various boat websites and certainly NO friend of Yanmar. Suspect he is the Yanmar moderator on Boatdiesel.com, and he takes no prisoners there. However he does have a huge following with boat owners who have been shafted like the OP. Working in the US for many years leads one to have what one might regard as a somewhat direct approach.......But it gets the job done!

We have been told sea trial numbers were OK....Comment drives me nuts, every time I am told this I go crazy, let us SEE the numbers. The answer to this mess is buried in the numbers somewhere. 'Not one of us is as good as all of us'.

I did comment in earlier post that I considered usining Yanmar 6LP's for this vessel a marginal call, which is why I asked OP to post displacement, which has never been replied to.
Power is heat, when you are pulling a LOT of heat out of one pot, over 70 Hp/liter. The Yanmar LP is a basically sound motor, however it is 'living life on the edge' in this application, everything has to be 100% correct. In the OP's case there is at least one factor which has been overlookerd, just a matter of nailing that factor?factors.

There were pretty much three options when the Detroits came out.

Cummins QSB 5.9 liters
Volvo D6 5.5 Liters
Yanmar 6LY2 or 6LY3 5.8 Litres

Somebody made a back of a fag packet calculation and advised that the 4.2 Yanmar LP would work in this application. That is where OP's problems started, condemned him to living .life on the edge'. OP has paid for what he thought was best advice and he has not had it. Worst of all still trusts the very people who slung him under a bus!
 
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Seatrial Numbers

Latestarter,

I think in general, "Day of Seatrail" numbers are mostly meaningless to the average vessel owner after the dust really settles.. I cannot think of ONE new or repowered planing hull that was powered, or repowered, for performance reasons ( that's what this repower was all about) that ever moved as easy as it did on seatrial day.


Can you?

It's always downhill from that perfect seatrial day as the days, weeks, and months pass. Somewhat like the hill you are climbing at 60 MPH in your car keeps getting steeper and needs more & more throttle pedal to maintain the same speed.


If the word typical applied, loosing 100-300 RPM at WOT as the vessel is outfitted & put into the working condition mode, bottom and running gear that only gets dirtier, etc etc, that this would be more likely. Yes, our poster has come back and said all was "Gucci" (at least on seatrial day) , but what does that mean with so much missing here after the fact, and with issues that really are not connected in the normal sense on this type of engine design?


Fishing Fool
 
I have not come back sooner as I have now taken the boat out and checked the WOT. It is 4000 on the starboard engine and a fraction under on the port. Say 3990. She is full of fuel (1400 litres) but no water on board and has recently been anti fouled. When sea trials were done after the original installation, and after fitting both replacement engines, she was low on fuel.

I thought I had replied about the displacement. 10 tons. Draft 3ft. Ray Hunt deep V hull.

I have checked with Marine Power who replaced the first failed engine and they also confirm that the tick list on sea trials was OK.

Are you saying that if the engines are the wrong ones for my boat this may have caused the injection pumps to seize? I assume there is a connection with viscosity and heat. On the second failure we had been running at cruising speed for about six and a half hours but on the first occasion the engines were cold.
 
CliffordGuernsey said:
Yanmar paid for the first engine to be replaced but are not interested in contributing to the second engine as it is out of warranty! At 315 hours it is hardly run in. Anyone buying a new engine needs to consider the manufacturer's attitude when things go drastically wrong. I find myself on average needing to replace a Yanmar engine every 150 hours.
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just as an extra separate route to follow..............

Guernsey adopts many English laws and it is worth you checking on your consumer protection laws.
In England an engine should last at least 6 years and some manufacturers provide a 6 year warranty (cummins being one).

Just because the warranty has expired doesnt mean the engine manufacturer can just walk away, assuming your engines are 3 years old and half worn out you should be able to fit a new one and request 50% (3/6 ) back from the manufacturer .

Get an estimate for replacement and send it to Yanmar stating that a marine engine should last at least 10 years and as yours has destructed itself in 3 you expect them to contribute 7/10 of your estimate (also include cranes,transport, hard standing etc).

You will need to include an engineers report as the the exact nature of the failure, in particular one that includes you have maintained the engines in accordance with manufacturers guidelines.
You really dont want to admit that the engines were wrong or have been installed incorrectly unless of course they recommended and installed them .


Hopefully they will recognise it will be cheaper to provide you with the repairs at their cost.
 
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CliffordGuernsey said:
I thought I had replied about the displacement. 10 tons. Draft 3ft. Ray Hunt deep V hull.

I have checked with Marine Power who replaced the first failed engine and they also confirm that the tick list on sea trials was OK.

Are you saying that if the engines are the wrong ones for my boat this may have caused the injection pumps to seize? I assume there is a connection with viscosity and heat. On the second failure we had been running at cruising speed for about six and a half hours but on the first occasion the engines were cold.
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My gut reaction is that the engines are simply too small for the weight of boat; 10t of deep-V takes a lot of pushing. They may well have performed adequately when first installed with everything clean and working properly, but once a bit of growth starts on the props/hull or the coolers get a little claggy adequate rapidly becomes inadequate.
 
Tach Readings

Clifford,

So, you are 100% sure your TACH readings have been verified against a photo tach and you personally confirmed that? If they are, then you will have the first ones I have ever seen that did't read about 125-150 high at the top end..

Fishing Fool
 
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