Mainship pilot 34 Survey

[Kuno]

I have an accepted offer on a 2001 Mainship Pilot 34 with a Cummins 6BTA 330 single engine with 3985 hours, a next gen genset and a Hurth transmission. The boat was clean and well taken care of and the survey showed it to be solid with no moisture problems. It has been a fresh water boat 99% of its life. The oil analysis was good for the engine and genset, but the Hurth transmission showed above normal small particulate 48001@ four micron, 8755@ 6 micron, 47 @ 14 micron, 19@ 21 micron, 6@ 38 micron, 2@ 50 micron. Does anyone have experience with rebuilding this transmission, or comments on oil cleanliness before I do a sea trial?
Brian

 

[DavidM]

Any oil analysis that measure to 4-5 decimal places is suspect. What do the numbers 48001, etc mean. Particles per ml, liter, ???

In any case I doubt if it is that bad. Hopefully Ski in NC will chime in. He should know.

David

 

[Beekeepergreg]

What are the other levels in the report?
Greg

 

[rgano]

The oil analyses I get from Blackstone have a column entitled "Universal Averages" which are the average for all the units of this type tested by them. Look for this on your report to get a perspective or send a sample to Blackstone.

 

[Kuno]

Mainship Pilot 34 oil analysis

I spoke to a rep at Toromont / Cat, The numbers I quoted are for oil cleanliness of transmission oil. A sample is taken in a syringe and placed into some kind of bright light spectrometer/particle counting instrument. They said the 6 & 14 micron size is most important and that it was slightly high on the 6 micron for Catapillar standards at 8755 particles in the small syringe sample. The other reading on wear for iron was 2 PPM or very low. I was told it is likely OK but to do a trend analysis over time. This type of test isn't done on engine oil because it is too dirty/dark to do. The generator had 11PPM of FE (iron) normal is 15-30, and the Cummins engine only had 3PPM of iron, or very low.
The ISO numbers were 23/20/13 on the transmission. They said the second number was slightly high, normally 18,the other ISO numbers are normal. The 20 represents 6 micron size. So I guess the transmission oil needs changing and retesting at the end of next season. Perhaps the transmission oil was rarely or never changed.

 

[Shrew]

They said ...... it was slightly high on the 6 micron for Catapillar standards at 8755 particles

'slightly high' is rarely ever on the verge of a rebuild. At what level do they suggest this be considered a serious/significant issue?

 

[Kuno]

Mainship Pilot 34 oil analysis

I have been told that these readings are all OK and that the Hurth ZF transmission is nearly bulletproof by a marine mechanic here in Ontario, so off to the sea trial.
Brian

 

[C lectric]

Those readings are a typical type of reading for industrial machinery hydraulic systems and gearboxes and are used to guage cleanliness of the oil in ISO standards. They are usefull IF the systems have a record of past tests to gauge whether the readings are increasing or decreasing. There is a two figure cleanliness rating which will indicate where things stand based on industry standards.

One thing I would say is missing is any history from the owner of previous testing which will tell a story. If the oil has been changed only infrequently or not at all for years then there will be a particle buildup. ALL MACHINES WEAR and in this case the only way to control the particle count is CHANGE THE OIL. If the oil has not been changed for to long then the readings may not be out of line.

If the oil was changed yearly then I would wonder.

A lot of people will change engine oil and totally or almost totally ignore the gearboxes/transmissions in their cars. Same for the boat.


Keep the tests. Change the oil after you get the boat. Do another test next year, do them yearly including for the engine and keep them.


Different engine, different gearbox but oil tests saved my bacon on a couple of occasions before other signs of brewing trouble showed up. Even if you don't understand them if you have them and you see a large change from year to year you can take them to you mechanic and question him.

If an opinion is wanted online then post a copy of the actual reports in PDF
so they can really be looked at. Snippets of info from posters often miss other important details/readings that can have a bearing on the opinion.

Sorry, My pet peeve about opinions of this nature.

 

[Kuno]

Mainship Pilot 34 oil analysis

Thanks for the reply C lectric. I will take your advice and continue trend analysis once yearly. I suspect the transmission oil wasn't changed very often as well. I attached the report for you to read.
Oil analysis saved my butt on a Lycoming aircraft engine when the mechanic found chromium in the oil. Came from the camshaft and one lobe was 1/3 worn through. Not a good situation on a single engine airplane.
Brian

 

[C lectric]

THe 48,000 is high as is the 8775 reading to me. Yet as said not out of line
if the gearbox has not had oil changes at engine oil change time.
If your mechanic is OK with it then good as he likely sees these things far more than I ever will.


If you go ahead with the boat purchase I would do several things to get that particle count down in minimal time.
--change the oil after a full warm up which will ensure the particles are in suspension.
--after the change run the engine in gear to stir up the new oil for 5-10 min in both fwd & rvs. Then take another test so you have a baseline of the new particle count.
-- after getting about 50 hrs on the new oil take another sample. If the particle count is similar then you should be good. A small change won't matter much as some particles may come out of hiding at this point.
--If the particle count is again rising a bunch then maybe there is a problem.

I will guess it won't be a big change. I would then do another oil change if it looks good AND take another sample for a new baseline. You want to continue dropping the particle count as quickly as reasonable..

THen do the next oil change at whatever interval you want to continue at. Most of us are yearly so do at the same time as you do the engine oil.
Each time take an oil sample and of the engine also.

Look at the link below for ISO readings as a quick guideline for their use..
https://www.machinerylubrication.com/Read/28979/iso-cleanliness-code

Good luck and happy boating.