This is a follow up to my earlier thread: "Engine Replacement Advise".
Approximately 2 weeks ago, my 2004 Volvo
(I have had since new) suffered a complete failure and requires either a replacement or a rebuild
. The engine
has about 750 hours on it. It has been maintained to a very high standard (oil and filter changed at least as often as the owner's manual states) and all parts
used have been OEM. The oil
level is checked religiously prior to each use and the engine has never been operated with a low oil
level. As a matter of fact, the engine did not have any oil leaks
, nor did it show any evidence of using oil, and prior to the failure, it ran quite smoothly. I have never experienced anything getting wrapped around the prop, etc.
The engine has been examined by the mechanic
working on it, as well as an independent technical expert hired by my insurance
carrier to determine the cause of failure. They agree on the cause. I have sent their information (as well as Volvo's theory of what happened) to another mechanic
, complete with photos, and he states: "I'd have to agree with the insurance
The report I received from the independent technical expert is as follows:
"Bottom end of failed connecting rod and bearing shows evidence of mechanical deformation and grinding due to pounding of the connecting rod on the crankshaft during operation. The bearing land on the connecting rod is not blued from extreme heat, which would have occurred had the bearing been starved of oil. The connecting rod did heat up as a consequence of pounding and failure of the hydrodynamic oil film, which resulted in lubricating oil 'cooking' onto the external surfaces causing the discoloration. The other rods and bearings show no evidence of oil starvation. The mechanic who disassembled the engine reported that he inspected the main bearings and found them to be undamaged.
The bearing cap shows evidence that the nut on the left was loose and came adrift prior to the failure as lubricating oil has cooked onto the surface where the nut would contact the bearing cap. The nut on the right side remained securely in place as the contact surface is clean. When the nut loosened, the normal bearing shape and clearance was disrupted causing failure of the oil film resulting in metal to metal contact. Once again, no bluing of the clean surface is evident.
The crankpin for #1 cylinder shows evidence of galling whereby metal to metal contact between the bearing and pin occurred as a result of the hydrodynamic oil film failing due to the bearing cap loosening. The crankshaft shows no bluing.
In my opinion, the engine failure is consistent with loosening of the connecting rod nut as demonstrated above."
Both the mechanic and the insurance technical expert agree that the cause of failure is that one of the nuts on the connecting rod for cylinder #1 came off which resulted in the engine failure. They both feel that this is the result of faulty workmanship or improper torquing of the nut during engine assembly.
I submitted all of this information to the Technical Support Manager for Volvo Penta Canada
. He has come to a completely different conclusion. He states that:
"Both the crankshaft and connecting rod are blue/black. The
only reason for this to occur is that the rod was either overloaded or
starved for oil and the rod bearing failed. If the rod nuts had just
come loose there would no signs of the blue/black colour.
The rod bearing failure would have been caused by a loss of oil or a
possible overloading. The top of the bearing becomes hammered from the
overloading and this leads to an eventual failure like this. If you
exam the other rod bearings you should see signs of this occurring in
the upper shells. If it was caused by being starved for oil the other
shells would show signs of wiping of the soft bearing material.
I am sorry to say that for these reasons we will not be offering any
kind of compensation for the repairs
The other rod bearings and connecting rods (except cylinder #1), as a matter of fact all other bearings, are in great condition, and Volvo has been told this to no avail.
I tried to post 3 photos to go along with this information, I hope they work because they clearly show the story.
Anyway, I am meeting a professional engineer
who deals with engine failure analysis tomorrow, and if he agrees with the mechanics and the independent technical expert, I am considering small claims court.
Sorry for the long post, but I felt this was important information for everyone to be aware of, especially if you are in the market for a new boat or a repower
. My advise is: AVOID VOLVO PENTA
PRODUCTS, because in my experience, they do not build a quality product, nor do they stand behind it.
However, for economic reasons, I am forced to rebuild
this engine, although if I could afford it, I would repower
with a Yanmar!