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Podjo · 01-07-2011, 06:56

Perhaps they used this synthetic purple transmission fluid?

Royal Purple Transmission Fluid

motion30 · 01-07-2011, 08:50

My question no cooler? I cant remember seeing a boat without a trans cooler If I had those failures I would have installed a cooler long ago Seems simple am I missing something here?

Target9000 · 01-07-2011, 09:03

Have you made 100% sure the alignment with the engine is correct? Use feeler gauges. Being out of alignment can screw a lot of stuff up.

Have you checked the motor mounts? Is there any vibration from the engine? Even if you have no alignment problems "normally" a faulty motor mount can cause the engine to buck and move as you run it and the boat. These can temporarily throw you out of alignment.

Have you checked to make sure nothing is on the propshaft? Have you checked the cutless bearing? Is the bearing worn to the point the shaft can wobble? How does your prop look? Nothing wrapped around it?

Put a long stick on the shaft while its turning and hold it while having someone idle, move the boat around in forward and reverse and different speeds. Do any sort of unusual vibrations telegraph through the stick to you? Look for anything that could be causing the alignment to go off.

When you shift the transmission do you shift quickly and firmly into gear or do you generally use a slow and gradual movement? I've heard the ZF/HBW gearboxes need to be shifted quickly and firmly, not a gradual movement. You want a firm quick "THUNK" into gear. Also check the linkages and make sure you have them set correctly.

How do you leave the transmission while under sail? Do you shaft lock it or do you let it freewheel? Do you leave it in neutral or reverse? Probably not an issue, but I'd check manufactorer specs and do what they recommend, or perhaps lock the shaft even if it isn't recommended just to see if that makes a difference.

To your original question... The fluid should be clear generally and most ATF is reddish, but perhaps others colors exist. Cloudy usually means it was overheated and burned. Put a magnet into the fluid and stir it around for a while, does it come up with a lot of metallic particulate? I'd also recommend you send it off for analysis as previous poster noted.

My suspicion is that you have an alignment or wobble issue that is taking its toll on your transmissions. I'd hunt for it.

Cheechako · 01-07-2011, 09:31

My Passport 47 had an 80 + horse Mercedes in it. The Hurth Gear was only about the size of a 6 pack of beer cans. It would get so hot you couldnt touch it even very quickly. The shaft was only about 4 inches long inside the packing nut so if the engine moved alignment was bad until it returned to position. It never failed. You need to write a letter to the CEO of ZF. I've heard too much of this on this forum and hope no one buys ZF's crap... perhaps you can find an old Hurth and overhaul it...?

Target9000 · 01-07-2011, 09:34

Quote:

Originally Posted by Cheechako

My Passport 47 had an 80 + horse Mercedes in it. The Hurth Gear was only about the size of a 6 pack of beer cans. It would get so hot you couldnt touch it even very quickly. The shaft was only about 4 inches long inside the packing nut so if the engine moved alignment was bad until it returned to position. It never failed. You need to write a letter to the CEO of ZF. I've heard too much of this on this forum and hope no one buys ZF's crap... perhaps you can find an old Hurth and overhaul it...?

I haven't search the forums about it but I have heard from several mechanics that agree with you.

When we ordered our new motor we had a chance to order it bobtailed and fit it up to our existing HBW gearbox (2004 model). I spoke to many mechanics and they all told me to ditch the ZF/HBW brand and go with the new transmission that comes with the motor. Some of them were calling the ZF's "disposable" transmissions. Yikes!

sgtPluck · 01-07-2011, 09:51

Thanks for the advice all.
I did speak to ZF again, they said that oil color would suggest the clutch was overheated. They said that this is usually because the shifter is not configured to completely engage the gear. I was fully aware of this as a potential problem when I put the gear in in May, and set the shift lever up to that it over-compensated in forward and goes well beyond spec.

My flexible coupling doesn't allow for testing with a feeler gauge because the shaft coupling part nests inside the flexible coupler.

The alignment tests I did were to rest a knife on top of the shaft and put it in gear, I did not discern any vibration or movement at all.
I did not try this at higher RPMs, and the possibility that under load my engine mounts might move and create wobble did occur to me. Honestly the only test I did on that was visual, I just stared at it for a long while while underway. At least visually I could not detect any wobble. I know it's not a proper test, but I felt the alignment would need to be visually discernable for it to be the cause of problems considering the flexible coupleing.

I do shift fast into gear.
The cutless bearing is quite new and in good shape, the prop had nothing on it. I just had it taken off and re-pitched, so now it is totally clean and polished.

ZF are going to send one of their technicians to look at the installation. Although the poster who went through 5 ZF15s had them out to look at it a couple of times.

I last changed the ATF oil in Nassau, and I think I only put 5-10 hours on the transmission since then and the oil is already burned. Unless I'm wrong about the alignment, or the shifting adjustment , the only other thing I could think of was that it just candle handle the load of pushing my heavy boat around. So I am praying that my de-pitching the prop might lighten the load and spare me having to replace yet another transmission.

If it does break again I'll probably put in PRM 80.

sgtPluck · 01-07-2011, 09:58

Only saw the last two posts after posting myself.

"Disposable transmissions" oy, that is scary. I've disposed a lot of money on them. It has really hurt my cruising plans.

I'm kicking myself a bit now, because when I was in Georgetown I was concerned about trying to put a PRM 80 in there that might require some reconditioning, so I got the ZF10m again and came back here thinking I'd find someone who could tell me what I had been doing wrong and fix it. So far I haven't.

I probably could have hobbled back on the gear I had, I didn't use the engine much

Target9000 · 01-07-2011, 10:04

Quote:

Originally Posted by sgtPluck

Only saw the last two posts after posting myself.

"Disposable transmissions" oy, that is scary. I've disposed a lot of money on them. It has really hurt my cruising plans.

I'm kicking myself a bit now, because when I was in Georgetown I was concerned about trying to put a PRM 80 in there that might require some reconditioning, so I got the ZF10m again and came back here thinking I'd find someone who could tell me what I had been doing wrong and fix it. So far I haven't.

I probably could have hobbled back on the gear I had, I didn't use the engine much

I'd still look into making sure the alignment is perfect before getting too worked up about it though. The mechanics I spoke to also told me that the 2 things that killed most of them was poor alignment and poor shifting practices. You already got the shifting down, sounds like the alignment is difficult to check. But it might be worth it since you're already in with the ZF to really get someone good on that and make sure its right. I bet you can make it last a long time if you get it perfect. I'm crossing my fingers for you.

beneteau-500 · 01-07-2011, 10:06

oil should be definitely Red as it goes in and out to me with out knowing for sure it sounds as if the engine is to big for the tranny what engine is it an horse power ? and what revs do you run ?

Captain Bill · 01-07-2011, 10:15

I just looked up the ZF10 transmission and it says that you need an oil cooler under certain circumstances. Specifically when running with the shifter in the B position and exceeding 25 KW continious input(33 HP). A or B ahead is determined by whether you have a right or left hand prop. How many HP do you have and which is your ahead shifter position?

Target9000 · 01-07-2011, 10:17

Quote:

Originally Posted by Captain Bill

I just looked up the ZF10 transmission and it says that you need an oil cooler under certain circumstances. Specifically when running with the shifter in the B position and exceeding 25 KW continious input(33 HP). A or B ahead is determined by whether you have a right or left hand prop. How many HP do you have and which is your ahead shifter position?

Excellent info!

sgtPluck · 01-07-2011, 10:21

Thanks Target9000, I will double and triple-check the alignment to be sure.

The engine is a Universal 25XPB. The specs for the ZF10 say it can handle 37hp continuous duty. But the detailed ratings are confusing, they say something about max rated power at 24hp at 2300rpm. I wasn't sure if that meant output or input power, someone told me it meant input.

http://www.marinepartsexpress.com/pr...07/ZF_10_M.pdf

Anecdotally, someone at ZF and someone at Foley said to me that they thought these gears were really meant for light in and out of the harbour duty.

sgtPluck · 01-07-2011, 10:23

I have a right hand prop, run in the A position and have a 25hp engine. So in theory at least, that shouldn't be the problem.

Astrid · 01-07-2011, 10:47

Quote:

How do you leave the transmission while under sail? Do you shaft lock it or do you let it freewheel? Do you leave it in neutral or reverse? Probably not an issue, but I'd check manufactorer specs and do what they recommend, or perhaps lock the shaft even if it isn't recommended just to see if that makes a difference.

according to the manual:

Quote:

Idling position of the propeller: gear
shift lever must be in «N» (Fig. 7)
position. Use the shift position opposite
to the direction of travel for
locking the propeller shaft, otherwise
the transmission will be damaged.