Dave, might be something as simple as the oil change was long overdue. Can you really be sure when the previous owner changed it? I would try keeping the oil changes on them closer to 50 or 60 hours for the next couple. If the tests look clean, then increase a bit and keep increasing until you find the sweet spot.
If you set up the drain plugs and hoses on them the oil changes will be quick and easy.

 

Good points John. I know the port was changed right as I took possession, as the there was a port screw that came loose and dumped all the ATF into the bilge on our maiden voyage. But I really don't know on the starboard, just an educated guess on the PO's part.

I did start reading up on these particle counts (there is a whole field of study devoted to machine fluid analysis), and by themselves, mean very little. Basically they are good for setting a cleanliness level for your fluids and as you suggest altering the replacement schedule to meet that level, with the expectation of a better service life.

Regardless, these gears are one of the weaker components on the boat as they are slightly underspec's for the 3126, so in the back of my mind, I'm preparing for the day that they will need to be rebuilt of replaced. I just hope its not tomorrow. In the mean time, I have put a lot of time and energy into servicing the entire system this year both on the hydraulic and electrical side in the hope of a carefree season.

I now have the EZ Oil 202's and I'm waiting on a new cooler for the starboard side. I did as suggested and soaked both coolers in Barnacle Buster, and they both look to be in excellent health. I am pre-emptively replacing the starboard as Frank suggested.

If something does go tits up, it wont be from a lack of effort on my part! Ill change at 50 hrs and report back.

 

It is critical that you know what the particles are, not just the particles count.

Brass and carbon can be just normal clutch pack wear which will be high if the transmissions were not serviced regualrly before you bought the boat.

Ferrous metal count is is critical and usually means gear, shaft or bearing wear and is something you need to keep up with.

Aluminum in the lube oil comes from the transmission case and is also critical since it usually means something is hitting the case during operation and that us usually a thrust setting problem internal to the gear box.

 

Thanks Frank. Reading and interpreting these reports is part of the learning curve. Here are the transmission Oil (ATF) results. Is that information detailed on the CAT SOS? I dont see anything in the base metals that indicate anything abnormal, and the newer reports add the particle count by size, but not what it is.

 

The main difference between the first and second reports is the particle sizes are categorized and an actual count is given in size categories for the later report.
The count on the port at 6 micron and less is about 30% higher than the starboard. No past history so can't tell if that is a concern or not. Particles of this size will not be captured by the filter, consequently will remain in solution. Particulate can originate from many sources, not just metallic.
Looking at the critical metals (copper, ferrite, chromium, and aluminum) nothing is alarming to me. Note also the earlier report appears to have been sampled with only 25 hours on the gear oil and the later at 100 hours on the oil so naturally the higher use will have higher indications.
These are good gears; the only issue is the port gear runs on the countershaft when in forward and the countershafts were not well supported; some failures were happening (mine was one in the 400DA).
Change the fluids and do another analysis at 100 hours is what I would do.

 

The Cat reports are a bit confusing, but when the samples were taken is also an issue.

To satisfy yourself, I'd suggest that you run the boat at normal operating temperatures for about an hour, then as soon as you get the boat secured, pull the sample with a Cat vacuum pump from 1/2 way betweeen the bottom of the dip stick and the bottom of the gear case.

Then, drain all the fluid into a spotlessly clean container and pour the drained fluid thru a paint filter or a scrap of high count linen cloth inside a funnel. Hope you don't have anything caught in the filter, but if you do, pass a magnet thru t he solids and see what sticks to the magnet. Stuff that sticks is from shafts, bearings, gears, etc. Bright shiney metal is aluminum from the gear case, and gold is usually from the clutch pack. Ferrous metal that is magnetic is not a good sign, nor is aluminum from the gear case. There will typically be some solids (black) from normal clutch wear in the fluid, but there shouldn't be ferrous metals or aluminum.


Last, I am not sure what standard the Cat SOS samples were cpompared to. For engine oil, Cat is superb because they know precisely what metals were used in building the engines and they have a statistically accurate standard for each. Therefore, you might want to use a general lab for future sampling on the transmissions.

 

David - on my CAT SOS transmission samples, the particle counts were high for 4/6 microns - my spin-on hydraulic filters are 10 micron, so the counts above 4 and 6 were low. Twin Disk said not to worry about it...

 

Those reports are not nearly as detailed as the SOS reports I get from the CAT lab in Newington, CT. I would bet your transmission fluid had much more than the 20 hours that was reported to you. If I were you, I'd retest and change the fluid at 25 hours and then again at the end of the season. I don't think yours have cartridge filters to change and I'm not sure if your transmissions have an internal strainer, but if they do I would remove, clean and reinstall it.

 

Were and how I sampled from might be the issue. I called CAT SOS and asked if the transmission oil needed to be hot, they said no, but it was warm from a run several hours prior. Also, I likely pulled from the bottom of the casing. Another contributing factor was not knowing the exact hours on the fluids.

I kept the old filters and intend to clean them and collect any material for analysis. I'll report back on that.

I just ordered a new starboard cooler, have new filters installed, New ATF ready to go and drain tubes to be installed. I'm going to fill her up and keep an eye on it. Also adding temp and pressure probes to help keep an eye on things.

 

It is best to have run the boat just before the sample is extracted as Mr. Webster laid out so the fluid is mixed and any particulate is in suspension.

 

Since Frank mentioned an outside lab, you may want to look at Blackstone.

 

Have a goid trip ! Drink some good scotch!

 

David,

This was from post #7:

"Then, drain all the fluid into a spotlessly clean container and pour the drained fluid thru a paint filter or a scrap of high count linen cloth inside a funnel. Hope you don't have anything caught in the filter, but if you do, pass a magnet thru t he solids and see what sticks to the magnet. Stuff that sticks is from shafts, bearings, gears, etc. Bright shiney metal is aluminum from the gear case, and gold is usually from the clutch pack. Ferrous metal that is magnetic is not a good sign, nor is aluminum from the gear case. There will typically be some solids (black) from normal clutch wear in the fluid, but there shouldn't be ferrous metals or aluminum."

To save you the question "what is too much and what is normal?" here is what I found when I strained the fluid. We suspected the port transmission had the countershaft problem, it was making noise so I serviced the transmissions and washed out the filters in February, hoping I could get thru the season before having to address the issue. But after seeing what was in the port transmission, I went ahead and ordered a new ZF85-IV, painted it and had it ready to install......I made it to the end of July. I did not let the transmission fail. There came a point when we had to come home on one engine and just used the port side for docking due to the noise the transmission was making. We changed it out before it slung itself apart.

The one on the left was from the port transmission with a failing counter shaft; the one on the right is the STBD side and shows what is normal clutch debris in the gear case and filter.

This is what you DO NOT want to see:

 

Frank

Thanks..I'm going to wash the filters, see whats there. Curious how many hours you had on it when the problem showed up?

For the most part my transmissions have been pretty good mechanically, at least I haven't heard any weird sound out of them. The biggest issue has been the rare, random and sudden loss of thrust on the starboard, and I attribute that to the wrong voltage solenoids and or just old crusty electric connections. Every inch of these transmissions has been gone over this winter, both mechanically, hydraulically, and electrically. and I'm hoping I've got it fixed.

Additionally, adding temp and pressure senders to keep a better handle on things.

Man I hope all the work and planning was worth it.

 

Frank

Thanks..I'm going to wash the filters, see whats there. Curious how many hours you had on it when the problem showed up?

I first heard a whine and a rattle when we changed gears in 2010........1069 hours. We had no idea what was going on but the transmission pulled well and did not slip. We decided to do as you are doing......contine annual servicing and watch it. At about 1200 hours, we decided we didn't like being stuck within single engine distance of our home marina so we ordered a transmission and made plans to haul the boat early and change the transmissions.

 

I finally had a chance to wash the filters. As suspected, there is ferrous metal in the port filter including one rather large chunk of machined surface. The starboard was pretty clean with "clumps of black material that was black but consistency of very fine mashed potatoes.

I did notice at the end of last season a whine from the port side when pulling it out of gear. Probably not good.

A couple questions...

1. Is there any documentation on the counter shaft issue
2. Is the transmission rebuildable or is the only option replacement with a 85IV?
3. Is complete failure imminent or do I have some time to prepare? Frank mentioned "slinging itself apart"...that doesnt portend good things for things attached like props, shafts and engines.
4. What does a complete failure look like?

Port Side

Starboard Side

 

See my PM response toy your questions....particularly the part about ordering a new transmission!

I would never rebuild a ZF transmission with this much metal in it simply because there is no way to remove all the metal that has been pumped thru the hydraulic pump and valves, bearings etc. A new ZF 85-IV is a sure fix.......a rebuilt Hurth 800-IV or ZF 80-IV is the same gear case you are slowly destroying. This isn't a little job @ about $10K, so you only want to do it one time.

The only suitable replacement is the ZF 85-IV because it is the same exact exterior case, the same ratio, and is a direct bolt in replacement with absolutely nothing to change except repainting the starter and engine behind the transmission.

 

Got your pm...Thank you. I’m in complete agreement going to need a ZF85IV and some big balls or a big check to fix it...sigh.

Of course, this is a lot like old houses. Once you pull the wall apart is when you find everything else that needs to be done.

 

Dt- you have a good attitude! As I look around for the “right one” issues like these make body parts pucker!

 

I did everything in my power to identify a decent boat, and for the most part succeeded, but as they say...you pays your money and takes your chances. It could be a year old boat and something could crop up. In the end they are mechanical, and can be repaired. This is going to be a lot more than I bargained for.

I’m feeling a little down about this one as I put a lot of effort into her this winter hoping for a trouble free 2019. I guess that’s not to be.

 

After having similar issues I can understand where you are coming from..all you can do is look forward to years of happy boating after the repairs are complete.
It would seem that this port transmission issue is common with the Hurth 800 gear.

 

David - I'm still not convinced you have a problem that requires replacement at this time. There are some things I would look further into like:
Have the filters ever been changed or cleaned?
The oil sampling was inconsistent consequently the analysis and indications have no real basis to make decisions.
High Chromium is not evident which if high be indicative of the countershaft tapered roller bearing failing.
All transmissions will create some amount of ferrite particulate; pull the pan off your car and look at the magnet in it; it's covered in carbon steel particles.
If the countershaft is becoming an issue it will noticeably knock when in reverse (on the port gear) as it is unloaded or free-wheeling when in reverse. With a stethoscope listen to both transmissions while someone is putting them in forward and reverse. Remember that the port gear in forward would / should sound the same as the starboard gear in reverse...
The larger chunk of carbon steel is curious but in it's self does not indicate really anything other than a chip came off something like a gear tooth which is not uncommon.
As a last thought you might consider scoping the gear with an endoscope and evaluate from there. Also you could sweep the bottom of the case with a magnet through the drain plug to see if there is an abundance of larger carbon steel fragments.
Just my thoughts.
Tom

 

David - I'm still not convinced you have a problem that requires replacement at this time. There are some things I would look further into like:
Have the filters ever been changed or cleaned?
The oil sampling was inconsistent consequently the analysis and indications have no real basis to make decisions.
High Chromium is not evident which if high would indicative of the countershaft tapered roller bearing failing.
All transmissions will create some amount of ferrite particulate; pull the pan off your car and look at the magnet in it; it's covered in particles.
If the countershaft is becoming an issue it will noticeably knocking when in reverse (on the port gear) as it is unloaded or free-wheeling when in reverse. With a stethoscope listen to both transmissions while someone is putting them in forward and reverse. Remember that the port gear in forward would / should sound the same as the starboard gear in reverse...
The larger chunk of carbon steel is curious but in it's self does not indicate really anything other than a chip came off something like a gear tooth which is not uncommon.
As a last thought you might consider scoping the gear with an endoscope and evaluate from there. Also you could sweep the bottom of the case with a magnet through the drain plug to see if there is an abundance of larger carbon steel fragments.
Just my thoughts.
Tom

Tom

That is excellent advise. I will do as you describe. I have been fooled before with this boat onto thinking i have a larger problem, only to discover that it wasnt as big an issue as origianlly thought upon further inspection and research.

However, it is an old old boat, and something will eventually crop up. The good news is you guys on CSR help me immensly, and im not afraid to turn some wrenches.