Normal to Top Off Transmission Fluid ?

[kfsf607]

Hi,
I have a Yanmar 3GM30F. Last checked the gear box fluid 1.5 years ago or so, and was right where it should have been on the dip stick...just under the groove. Checked again tonight, and was barely registering on the stick. Is it normal for the fluid level to drop, needing occasional top offs, or do I have a leak? No fluid visible under the box or engine. Transmission runs fine. A bit worried because have not ever changed the engine feet, and seems it vibrates a lot. Perhaps blew a seal with vibration?? Planning on replacing the feet next month during haul out. Any thoughts?

[Sunspot Baby]

Wow. I suggest a more frequent lube level check.

Do you see visible signs of a leak?

Gearboxes don't typically use oil so it is probably leaking but after 1.5 years is could be a very small loss and an occasional top up easier than fix. You need to track this and determine where it's going.

George

[GordMay]

What George said.

[Minggat]

I would think a leak that slow would not leave much teltale. Put white anything under it and maybe maybe you could see where it's coming from. But to try to eliminate it could be an exercise in splitting hairs.

[kfsf607]

Thanks for your feedback. Am religious about changing the engine oil every 75 hours, but definitely dropped the ball with the gear box. It is white and clean underneath and no streaks on the engine or shaft. Will top off and keep better track of it. Thanks for the feedback.

[PamlicoTraveler]

I change the transmission fluid every 500 hours because I heard it was wise to do that, and it's no big deal to do it. You only use one gear, so it probably should last a long time. I would fill it and check it and I bet it will never be a problem.