Help With Oil Analysis

[markpj23]

So we just competed the engine survey on our (hopefully) soon to be new boat, a Marine Trader Med Yachts 62. Has J&T 6-71 TIBs 435 HP.


Oil analysis all came back 'good' but I noticed a REAL difference in the port transmission sample as compared to STBD. Specifically, the fine particles counts and the metals indications.


I've asked the surveyor to explain / comment but have not heard from him yet.



Hoping that some of you oil & engine gurus might take a look and advise if I should be concerned? I've posted the engine samples also.



Many thanks in advance....

 

[O C Diver]

First question would be if the oils in the 2 transmissions were changes at the same time? If they're vastly different hours on the two, that could be part of the difference. Copper I believe can also be clutch plate wear. The lead would be a concern as I believe that's relative to bearings. Sodium is also one to watch as a significantly elevated level can indicate a transmission cooler going bad (Sodium as in salt from saltwater).

For oil analysis to be more helpful, you need to see a number of tests over time (trends) with known intervals and oil changes.

I would change all oils to establish a baseline and reanalysis the transmissions after 100 or 200 hours. Personally I prefer Blackstone for oil analysis as it's easier to compare multiple samples of the same engine or transmission. Also, they're very receptive to calls about their testing if you have concerns.

Ted

 

[Comodave]

When we bought a previous boat some of the analysis numbers looked out of line. But like Ted said it was one sample and I didn’t have a history to compare it to. So we bought the boat anyway and never had any issues with it as far as engines and transmissions.

 

[Barking Sands]

Any past history on oil/fluid changes or samples available? Without knowing the last fluid changes its tough to know or extrapolate.

If you are moving forward with purchasing this boat, once it is in your possession I would change the oil/fluid in everything that will be sampled at one time. Operate for some number of hours whether it be 100 or some other number, then carefully take new samples and send out again. If they are all acceptable I would then make these my baseline samples. All future comparison would be measured against this and monitored for change. Keep in mind if the previous owner did not change fluids at regular intervals, or out of phase intervals...the sample after the sample described above could actually come back lower yet again. If that happens use the latest best sample as the baseline.

 

[tiltrider1]

The oil analysis states that both oils had 25 hours of use. The analysis also states that the elevated copper appears to be leaching from the heat exchanger. My guess is the port heat exchanger failed and was replaced. It now appears to be time to replace the starboard heat exchanger.

 

[O C Diver]

The oil analysis states that both oils had 25 hours of use. The analysis also states that the elevated copper appears to be leaching from the heat exchanger. My guess is the port heat exchanger failed and was replaced. It now appears to be time to replace the starboard heat exchanger.

I would need to verify the hours on the oil. Not sure I believe a surveyor pulled all the oil samples, researched the oil hours and sent them off for analysis. Also, were those engine oil hours or transmission oil hours? Could see the engine oil changes logged, but most people do multiple engine oil changes for each transmission oil change. 25 seems a nice easy number for someone to pick. 27 seems more like someone actually researched it. Amazing how both engines have the exact same hours (to the tenth) on the oils for both the engine and transmission. Also seems like a lot of lead for 25 hours.


Finally, it would seem like a fair amount of wear metal for only 25 hours on each engine. Where I'm going with this is that I don't think the 25 hours on the oils is real. While the wear metals in the one transmission are concerning and it may be time to change that transmission cooler, interpreting wear metals usually requires absolutely knowing real engine oil hour numbers and use patterns.

Ted

 

[SteveK]

Total engine hours are same used for trans hours. All 4 are shown as 25 in use.
I would change the port cooler and trans oil. Also check condition of zincs if any

 

[markpj23]

Thanks for the replies.


Seller reported the hours since last oil change, so that was the basis. Reportedly all components had oil changed at the same time.


Interesting that the seller says the port transmission oil cooler was replaced about a year ago, and that is the one leaching copper. Is that significant or normal for a 'new' cooler?

 

[O C Diver]

Interesting that the seller says the port transmission oil cooler was replaced about a year ago, and that is the one leaching copper. Is that significant or normal for a 'new' cooler?

I don't know about leaching. Maybe some manufacturering dust /granules? If it was lead soldered, maybe that explains the high lead content?

It's difficult to interpret wear metals on low hour oil. When an oil change is done, not all of the oil comes out. If the engine wasn't run quite a long time there may be residue in the pan. When new oil is added, the wear metals may be higher as the new oil may pick up the residue.

A final thought, if sampling through the dipstick, the sample tube may have gone to the bottom of the transmission and picked up some old residue. This is why I oil sample and change oil after long runs. Residue should be thoroughly suspended in the oil for both sampling consistency and removal with oil change.

Ted

 

[psneeld]

I had a bit higher than my usual copper in my last oil samples...and research revealed copper leaching is typical in marine engines.

Also had a bit higher in iron.

Both can be explained by the engines sitting longer than normal and oil samples taken at vastly different oil sample frequency according to my research.

But that's for an engine, not a tranny.

 

[Slowmo]

The analysis indicates different lubricant formulations are in the two transmissions. No brand or hours are provided. This combined with vastly different wear metals suggests strongly that the starboard transmission has had much more recent oil change. Without knowing operational hours it is difficult to interpret the wear metals analysis. The Ca and Mg levels clearly give away that the formulations are different. These are the detergent package, these don't go away with time. The additive metals have some hallmarks of Chevron Oronite additive technology. This could suggest Chevron Delo but of different ages. However as Oronite sells to many oil marketers around the world the lubricant brand could be another...though in the US I'd lean to Chevron Delo.

 

[Island Cessna]

I don’t know what material is used for clutch disk facing in these Capital gears. Some oil flooded clutches use paper-like fiber material, but some use sintered soft metal. If the latter I would add clutch disk wear to the list of possible sources. The elevated fine particles would point to wear rather than cooler metal corrosion.

Does this gear perhaps have a trolling valve? If so clutch slippage and associated wear may be normal. If it has a trolling valve an external oil filter is often installed, and overlooked when servicing.

 

[C lectric]

Copper leaching can be higher from many causes including new.

I have attached an article below about high copper in oil.

I remember also someone here wrote that they were having high copper problems, warnings. The post was fairly recent. He finally figured out it was caused by his oil changing system which used brass/bronze gears which have high parts of copper in their construction.

Some systems use brass/bronze gears and some use a rubber impellor.

I do not remember who it was and of course I did not bookmark the thread.

 

[psneeld]

Copper leaching can be higher from many causes including new.

I have attached an article below about high copper in oil.

I remember also someone here wrote that they were having high copper problems, warnings. The post was fairly recent. He finally figured out it was caused by his oil changing system which used brass/bronze gears which have high parts of copper in their construction.

Some systems use brass/bronze gears and some use a rubber impellor.

I do not remember who it was and of course I did not bookmark the thread.

That was one of the articles I read in my research... The avearges chart sure made me relax a bit more.

 

[SteveK]

The analysis indicates different lubricant formulations are in the two transmissions. No brand or hours are provided. This combined with vastly different wear metals suggests strongly that the starboard transmission has had much more recent oil change. Without knowing operational hours it is difficult to interpret the wear metals analysis. The Ca and Mg levels clearly give away that the formulations are different. These are the detergent package, these don't go away with time. The additive metals have some hallmarks of Chevron Oronite additive technology. This could suggest Chevron Delo but of different ages. However as Oronite sells to many oil marketers around the world the lubricant brand could be another...though in the US I'd lean to Chevron Delo.

Are you saying two types? Like ATF, gear, engine oils different.

another possibility to consider is that the samples were mislabeled and reversed.
I actually found that after purchase and doing my own tests. The OP says port has a new cooler which suggests the starboard cooler needs to be changed. OR the port cooler was changed but not the oil before the tests.

 

[markpj23]

I don’t know what material is used for clutch disk facing in these Capital gears. Some oil flooded clutches use paper-like fiber material, but some use sintered soft metal. If the latter I would add clutch disk wear to the list of possible sources. The elevated fine particles would point to wear rather than cooler metal corrosion.

Does this gear perhaps have a trolling valve? If so clutch slippage and associated wear may be normal. If it has a trolling valve an external oil filter is often installed, and overlooked when servicing.

No trolling valve. Interesting to note that while in neutral at idle, the port shaft would spin at (estimated) about 5 rpm while the stbd shaft was stopped. Engine surveyor said that was nothing to worry about.


Just more port transmission questions though in my mind...

 

[psneeld]

What type of stuffing box?

Traditional would mean one is tighter than the other.... could also be a touch of misalignment or cutlesd bearings.

 

[markpj23]

What type of stuffing box?

Traditional would mean one is tighter than the other.... could also be a touch of misalignment or cutlesd bearings.

Dripless seals. Cutless bearings redone about 3 years ago and are tight.

 

[psneeld]

Still doesn't mean there is a serious issue that one shaft turns more freely.

 

[jleonard]

Still doesn't mean there is a serious issue that one shaft turns more freely.

I had a Chris Craft single inboard that the shaft turned at start up when the oil was cold. Even with a new cutlass and tight packing it still turned a little.
Sometimes all the stars line up.

 

[hfforeman]

Transmission Oil (regarding the fine particle count)
Typically, the spin-on filters for Engine and Hydraulic are rated at 25-microns.
So, all the little fine particles smaller than 25-microns will stay in the sump.

The thought is, that changing the oil SHOULD have removed much of the fine particles in the transmission oil.

**IF** it has only been 25-hours since oil change, then there is only a few reasons that would cause this.

Sludge - Perhaps they did not get the oil hot and stirred up before pumping out. Then they would have put new oil on top of the old sludge.
Poor Sampling - Somebody mentioned that previously. Sample should be taken with equipment at operating temp and in case of transmission or engine, from the same spot each time and while machinery is running. (ideally a petcock off the pressure line somewhere easily accessible).

I am just guessing, but I would 'guess' that the boat sat for a long time, with not much full throttle operations, the sludge built up, and the oil was changed when the engine was cold.

To remove -
a - There are many products and techniques out on the market that can 'flush' the system and then allow you to drain off the old (warm)oil with most of the small contaminants.
b - On major ship and drill rigs, we use a centrifuge to constantly take out those smaller particles that the pleated paper filters cannot. Ours were big units, but CAT and other engine manuf re-sell these lube oil bypass filters for their engines. For the smaller guys, like diesel trucks and boats, they sell smaller 'by-pass' systems that centrifuge a portion of the oil flowing through the systems to clean it up. The expense only makes sense if you have a HUMONGOUS amount of oil to change out, like 2,000 gals of DTE32.

Bottom line - Much easier to use the Flush additive/technique before changing oil.

 

[Steve DAntonio]

Copper is a natural wear metal for hydraulic transmissions, the wet clutches are made from sintered bronze which contains copper.

The common saw about needing to compare an analysis against a series of previous analyses is simply incorrect. A sample that indicates the presence of coolant, sodium or other contaminants, or excessively high wear metals can be definitive, provided the sample is taken properly, and the results are analyzed by someone who is trained to do so, a tribologist. I've never met a surveyor, hull or engine, who had such training. I'm not faulting them, it's simply not the sort of training they consider worth paying for. If you have questions about the sample report, I would contact the lab.

Above all else, the computer axiom, 'garbage in, garbage out' applies to fluid analysis. The samples must contain all relevant information, especially and including accurate 'lube time', i.e. how many hours are on the oil, as well as "unit time', hours on the gear. This is critically important, because oil with 10 hours on it has a far lower threshold for contaminants and wear metals than an oil with 500 hours. If the lab isn't provided this info, then they may apply an arbitrary number, or zero, as if it were new oil, in which case thresholds would be very low.

Does the oil on both transmissions really have only 25 hrs? Sampling errors can also account for erroneous readings, i.e. dragging the suction tube across the bottom of the gear housing will dredge up years of wear metal, as will reusing sample tubes. There are many ways to take a fluid sample incorrectly, and only one way to do it right.

More here....

https://vimeo.com/sdmcinc

https://stevedmarineconsulting.com/oil-analysis-3/

https://stevedmarineconsulting.com/wp-content/uploads/2014/03/FluidAnalysis143_Final.pdf

 

[Steve DAntonio]

Transmission Oil (regarding the fine particle count)
Typically, the spin-on filters for Engine and Hydraulic are rated at 25-microns.
So, all the little fine particles smaller than 25-microns will stay in the sump.

The thought is, that changing the oil SHOULD have removed much of the fine particles in the transmission oil.

**IF** it has only been 25-hours since oil change, then there is only a few reasons that would cause this.

Sludge - Perhaps they did not get the oil hot and stirred up before pumping out. Then they would have put new oil on top of the old sludge.
Poor Sampling - Somebody mentioned that previously. Sample should be taken with equipment at operating temp and in case of transmission or engine, from the same spot each time and while machinery is running. (ideally a petcock off the pressure line somewhere easily accessible).

I am just guessing, but I would 'guess' that the boat sat for a long time, with not much full throttle operations, the sludge built up, and the oil was changed when the engine was cold.

To remove -
a - There are many products and techniques out on the market that can 'flush' the system and then allow you to drain off the old (warm)oil with most of the small contaminants.
b - On major ship and drill rigs, we use a centrifuge to constantly take out those smaller particles that the pleated paper filters cannot. Ours were big units, but CAT and other engine manuf re-sell these lube oil bypass filters for their engines. For the smaller guys, like diesel trucks and boats, they sell smaller 'by-pass' systems that centrifuge a portion of the oil flowing through the systems to clean it up. The expense only makes sense if you have a HUMONGOUS amount of oil to change out, like 2,000 gals of DTE32.

Bottom line - Much easier to use the Flush additive/technique before changing oil.

Sludge and varnish are common contaminants in crankcase oil, but not gear oil as there are no combustion byproducts.

 

[markpj23]

Thanks again for the replies.


I think at this point we have a baseline sample to use going forward. Seller hired the last oil changes done and I don't know how well he supervised the work. Like several have said, there are many ways to mess up an oil change and/or sample.



I will change out all fluids after equipment warm-up and then do another analysis after 100 hours run time (or whatever the correct interval is for 6-71s).


Thanks again to all who replied.

 

[fryedaze]

Sharing oil analysis for 1989 6BT5.9M. 6700 hrs. Run at 1500 hrs 95% of it's life. View attachment 89 MONK 42-S-220405.pdf

 

[fryedaze]

Sharing oil analysis for 1989 6BT5.9M. 6700 hrs. Run at 1500 hrs 95% of it's life. View attachment 127774

Oh well the pdf wouldn't download.

 

[SteveK]

Downloads for me. Yes a good report. Starboard engine suggests there is a Port engine, is it as good?

 

[O C Diver]

Dave, that looks like a good report! Do you have a rough idea of fuel consumption per hour at your average cruise speed?

Ted

 

[fryedaze]

Downloads for me. Yes a good report. Starboard engine suggests there is a Port engine, is it as good?

Waiting on the port email

 

[fryedaze]

Dave, that looks like a good report! Do you have a rough idea of fuel consumption per hour at your average cruise speed?

Ted

3.5 gph at 7.8 knots. 1500 rpm.
I see I put 1500 hrs in OP instead of rpm
Approx 24,000 gal burned