gear box oil

[KREW2]

Hi
I have just viewed a 2004 Seaward 25 fitted with 2 x 125 Yanmars and, my offer has been accepted. She looks as if she has been impeccably maintained, but the gear boxes are confusing me.
Both dipsticks showed only dribble of clear fluid at the very bottom, so it is not ATF . What else I found confusing was there was only one mark on the stick, about 10mm from the end. This to me suggests that the mark shows the maximum, and the ideal level is half way between the bottom of the dip stick and the said mark, also whatever gear boxes they are they don't use ATF.
I'm sure an explanation from the owner will clear things up, however any knowledgeable advice will be appreciated thank you.

 

[Portofino]

With Twin Disk s you check when warm and ticking over in N .Not off and cold .
Pump has to pump it around a bit to get the correct levels .

It single weight oil not ATF Eg W 30 or W 40 depending on the climate .

No oil means low pressure and no mating of the disks / clutch pack so it won’t get out of N .

You should have G box oil pressure gauges on the dash or screen ? Talking 18/19 bar needed to engage the “disks “

 

[Portofino]

Twin clutch packs or “ disks “ explained here .

 

[KREW2]

Many thanks. A lot more going on than I realised in there. I will look at the video in detail later.

 

[KREW2]

You should have G box oil pressure gauges on the dash or screen ? Talking 18/19 bar needed to engage the “disks “

I am quite a long way from the boat, so just popping over and looking is not really an option. Here is a picture of the control panel. Does anything on there look like a gearbox oil pressure gauge , thanks.

 

[Portofino]

^^^ Not to me .Just a Yanmar bit showing engine temp , oil P , hrs , and rpm along with the boat builders fitted fuel gauges + trim .
Its the builder who will fit g box gauges as the engines probably supplied “bob tailed “

Builder choosing the G boxes, propulsion system ie straight shafts etc , and fitting exhaust s ……..within engine manufacturer s specs and usually sign off at hull no 1 .

I think you are over worrying .Find out what make of g box Eg Hurth , ZF , or Twin disk and Google operator s instructions/ maintenance .
I understand some small ZF do indeed have ATF , it will say in the manual .

As I said no oil or low oil = stuck in N because the clutch packs cannot compress together , there should be a pressure guard = alarm on that red LED panel to the RHS of the Yanmar instruments?

 

[KREW2]

I have asked the broker to get me the model of gearboxes.
Judging by the condition of the boat and the outward appearance of the engines, the owner has been quite meticulous. I noticed who ever did his servicing used all genuine Yanmar filters. So I cannot see them putting the wrong oil in, or not enough in both gear boxes. You are probably right I am over worrying.
Thanks again.

 

[rafiki_]

Very unlikely that you will have a gearbox oil pressure gauge in your instruments.