Capt No Slack
New member
2001 yamaha 25hp 3cylinder 2 stroke (model #25MSHZ3)
Was changing my lower unit oil and noticed only 5 ounces came out, concerning because the specs claims the gear case holds 6.8 ounces. Plus the drained gear oil was slightly cloudy/milky.
So I remove the lower unit and pressure tested it at 10psi, I noticed bubbles around the shift shaft seal/boot and the drive shaft seal. The good news it there was no leaks/bubbles around the prop shaft seal.
I am mechanically incline however I have never changed/replaced the shift shaft and drive shaft seals of any lower unit.
So I am seeking advice and how to do it.
Ive looked at the yamaha exploded parts diagram it looks like the shift rod seal/boot would be fairly easy to replace?
I removed the black plastic water pump housing, metal cup, impeller, metal wear plate and gaskets. However there is a metal base to the water pump (from the parts diagram it is listed as part number 663-44341-00-94 HOUSING, WATER PUMP) it has two dowel pins stuck in it. HOW DO YOU REMOVE THIS PART, it seems pressed in to me, I do not see any bolts or screws holding it in place?
I have attached some photos.
Can I replace the drive shaft seal and shift shaft seal myself or should I just take my lower unit to a yamaha dealer and let them do it.
any advice will be appreciated.
Was changing my lower unit oil and noticed only 5 ounces came out, concerning because the specs claims the gear case holds 6.8 ounces. Plus the drained gear oil was slightly cloudy/milky.
So I remove the lower unit and pressure tested it at 10psi, I noticed bubbles around the shift shaft seal/boot and the drive shaft seal. The good news it there was no leaks/bubbles around the prop shaft seal.
I am mechanically incline however I have never changed/replaced the shift shaft and drive shaft seals of any lower unit.
So I am seeking advice and how to do it.
Ive looked at the yamaha exploded parts diagram it looks like the shift rod seal/boot would be fairly easy to replace?
I removed the black plastic water pump housing, metal cup, impeller, metal wear plate and gaskets. However there is a metal base to the water pump (from the parts diagram it is listed as part number 663-44341-00-94 HOUSING, WATER PUMP) it has two dowel pins stuck in it. HOW DO YOU REMOVE THIS PART, it seems pressed in to me, I do not see any bolts or screws holding it in place?
I have attached some photos.
Can I replace the drive shaft seal and shift shaft seal myself or should I just take my lower unit to a yamaha dealer and let them do it.
any advice will be appreciated.