ZF 63A loud whine at idle

[JediJD]

I've been going through a long checklist of items on my Carver (I know...but I was a Sea Ray guy a long time and will be back shortly), and have something I can't quite get my arms around. At idle, the port transmission has a high pitched whine. Its almost like a squeal...sounds metal to metal, not pump sucking air sounds, and I've been in the engine bay listening and can't seem to narrow it down. Engaged, seems to be fine both forward and reverse. Starboard tranny actually looks a little sloppier but quiet as a churchmouse. I'm a freak for service. I got transmission oil samples before purchase which didn't show anything out of the ordinary, and I've serviced the transmissions in the meantime, fluid levels are perfect, oil is a light red and clear. Roughly 450 hours on the engines and (presumably) the transmissions. Shafts and props seemed right, props propscanned a couple of years ago. This may have been going on for a while and I haven't noticed, or it may be getting more pronounced...hard to say, but it is definitely noticeable now. Guesses? Thanks in advance.

 

[carterchapman]

Charles - I don't know anything about Carvers - but - Try to isolate the where the sound is coming from with a stethoscope or a screwdriver held to your ear. Then drain the fluid and catch it in a clean pan. Next, remove the filter and put it in a clean bowl or pan and wash it out with mineral spirits (not lacquer thinner - you want the solvent to flow thru the filter and wash out foreign matter, not evaporate so fast that it leaves junk in the filter) , then, let it drip/air dry overnight. Last, filter the wash solvent and the transmission fluid as you pour them into a clean can or bucket for disposal. Do this with a Mr. Coffee paper filter....it takes a while but it will strain any debris out of the fluid/solvent. Do the filter wash solvent separately from the ATF. Retain and examine whatever is filtered out of the solvent/fluid. Pass a magnet thru it and see if or how much of the debris is ferrous metal (bearings, shafting, gears, etc) how much is silver (aluminum from the gear case) and how much is gold (brass from the clutch pack.
The absence of a lot of debris is a good thing, but any marine gear is going to have some crap in it from normal clutch wear, so don't get alarmed.
Noise ahead of the transmission in the bell housing is also a good thing since a new transmission is about $6500. A noise at the center top of the transmission is likely the hydraulic pump. I don't know if it is replaceable from outside the transmission on the ZF-63 gear or not. ZF usually buries them inside the transmission which means the whole shooting match has to come out of the boat to fix it.

I don't know the layout in your bilge space, but my gut feel is that the labor to remove the transmission for replacement or repair is likely going to be expensive and require pretty much disassembling the salon. On most smaller bridge boats you have to pull the engine and transmission as a unit because there is limited space to separate them.

Let us know what you find.

Best to you and the Only Mate.

 

[JediJD]

Captain Captain! How the heck are you! Thanks so much for the post. Miss seeing you about. Mi barco su barco. Thanks for the advice...gives me some direction. Fortunately, its a Vdrive, with relatively lots of access room. I say this before trying to pull it out, but I'm thinking it will only be a back breaking bear, and not require the boat to be Sawzalled in half for access...but its early. I'll start looking at pump options. I needed to learn how these things work anyway. Keep in touch! Would have been a bit easier if you had said..."sounds like the twiddle switch has emulsified, just order a new one for $50 and that'll do it" but such is rarely my destiny.

Best to you and yours!

 

[carterchapman]

Come visit us at Lake Chickamauga! We miss you guys!