Analysis of DD 6V53 oil samples

Appreciate some feedback on these oil samples, compared to maximum allowable, and in consideration of the engine hours. Not sure if these are souped up J&Ts, but they are 400 hp and 2500 hours. Unfortunately there is no feedback on how the previous owner has operated them, but I've often read that at full levels, if run to the pins, it's unlikely to get much over 2000 or 2500 hours life out of them. The wear levels don't seems bad, so perhaps they've been run more moderately.

Just looking for some feedback. Thanks.

Hours on the oil? Port and starboard same hours on the oil?

As above, need to know the number of hours on all of the oil samples.

Several numbers jump out at me without even knowing the hours.

First one is the soot on the starboard transmission. Shouldn't be seeing soot in a transmission unless there's a serious problem.

Second is sodium in the generator. Typically, sodium is salt that is most often associated with transmission cooler leaks. A raw water cooler (in saltwater) can weep salt into the transmission oil (had that problem once). Usually replacing the transmission cooler and several oil changes fixes the problem, unless it's been going on for a long time or a lot of water. In a generator, sourcing the problem may be more difficult as lube oil and raw water usually aren't in a cooler together.

The lead number in the generator is VERY troubling. Lead is often from the main crankshaft bearings. I would expect to see 0 to 3, not 14.

In general, my guess is that generator went a loooong time between oil changes based on the elevated numbers.

I tend to be a pessimist (optimist with experience) when it comes to one off oil numbers. You may be able to spot problems, but you can also dramatically obscure problems with two oil changes within a few operating hours before oil sampling.

Ted

"irst one is the soot on the starboard transmission. Shouldn't be seeing soot in a transmission unless there's a serious problem."

I would suspect a typo since the port engine has no soot number reported.

Appreciate the feedback. I don't have the hours between oil change unfortunately.

The genset is strange as it has low hours, is original to the boat, yet the analysis (lead, iron, pretty much every other metal) indicates that it's in sorry shape internally.

The soot in the marine gear does not appear to be accompanied by high levels of metals, but I'm wondering if it could be an indication of a worn-out clutch pack. Also, this boat has electronic shifters and I often see operators abusing the quick-shift capabilities when docking. Some iron in there, so perhaps some water mixing in the oil cooler. Are those TD's seawater or freshwater cooled?

It's been my understanding that oil samples work best at showing trends, so you need at least a few of them. I'm unclear what basically snapshot is going to tell you unless it's maybe something really wrong. Looking at the one you have, the numbers on the 2 engines look close to each other and the same with the 2 gears. The generator has some numbers that are higher than the engines but maybe that just means there are more hours on the oil.

Mako said:

The soot in the marine gear does not appear to be accompanied by high levels of metals, but I'm wondering if it could be an indication of a worn-out clutch pack. Also, this boat has electronic shifters and I often see operators abusing the quick-shift capabilities when docking. Some iron in there, so perhaps some water mixing in the oil cooler. Are those TD's seawater or freshwater cooled?

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Many clutch packs have copper discs. Would expect to see copper if there was a clutch problem. With soot, I would expect to see something burnt, like oil. Maybe an issue in the hydraulic pump on the transmission.

I would consider talking to the lab that did the analysis. While I only have experience with Blackstone, I would assume that most will talk you through the analysis that they produce. Blackstone certainly does.

Ted

I like 6V53 JT 400hp engines. They are hot rods. Usually you find these in 25+kt boats and fast is fun!

They are fairly inexpensive to overhaul which is a good thing because getting 1.25hp out of a cubic inch of displacement is a recipe for short life. 2500 hours out of a 6v53/400hp is a good goal but be prepared for less. On the other hand diesel engines wear out by the gallon not the hour so if the excess HP is not used these babies will live for ever.

I just have no fear of these engines. I see nothing catastrophic in the sample, tHats the best I can come up with from one sample with no know time on oil. I did not say these engines are good. All I said was fast is fun and I am prepared to pay for fast.

But! What do I know, I drive a Ferrari that’s fast and fun!