Fitting impeller - Yamy 25/4

[Luc]

Some help please.

As I was idling to the boat ramp at Scabarough, the water from the telltale reduced to a trickle.

Not crap in the telltale but still only a trickle of water when flushing at home.

So I'm up for a new impeller. I just want to know if there are any little quirkies when doing this job.

I do most service work on my ute & car so I don't anticipate any problems with the outboard.

Luc

[Willdoe]

I think there was a post on this job not so long back. I'm not sure about Yamys but I have done Mercs and Mariners several times. It not a hard job for anyone with a little mechanical knowledge.

1)Disconnect the gearshift linkage if it is up in the engine cowel. Alternatively it could be a splined connection possibly down near the gearbox, - for a splined connection the linkage shaft that runs down the leg rotates when changing gears and will part when the gearbox is removed at step 2).

2) Motor on tilt, remove the prop and split the leg just above the gearbox - usually 3 nuts . If there is a trimtab check there isnt a stud and nut under it. The lower leg should slide off.

3)Remove the pump cover, (note the lay of the impeller vanes - which direction they bend- a photograph can help ).

4)slide the impeller off - don't loose the key. If your lucky you may only have to replace the impeller but sometimes the stainless bottom plate and pump cover liner can be worn. If in doubt check with your friendly dealers mechanic.

5) Check if there should be small tefflon spacer washers either side of the impeller when at the dealers getting the impeller and any gaskets. These sometimes disappear with wear but can be important in maximising the life of the pump. Reinstall the key and slide the new impeller over it.

6) Smear rubber grease on the inside of the pump cover and gently push it on while rotating the drive shaft in the normal direction of rotation. This should lay the impeller vanes in the right direction mentioned in 3) above.

While you have the leg off you could try connecting a water hose to the water pump outlet tube in the leg (if appropriate adapters can be found) and see if you can get a flow out of your telltale.

7) Grease the shaft spline with an appropriate grease and also the water tube in the leg, and slide the lower leg back into place and bolt it on. This may take a little bit of jiggeling to line up the spline, the pump with the outlet tube and the gearshift linkage but generally isn't too difficult. If the gear linkage connection was splined it is important that the gear shifter and the gearbox is in neutral when they are joined.

8) Reconnect the gear linkage if it is in the cowel.

Note: always grease threads when reinstalling nuts. but stay clear of lubricants that contains metals such as copper coat or molydinum. I've heard they can cause corrosion and actually make parts grow together.

9) Connect up the flushing gear and give the motor a test run.

10) Stand back with a cold stubby and congratulate yourself on a job well done.

Willdoe

[Willdoe]

I think there was a post on this job not so long back. I'm not sure about Yamys but I have done Mercs and Mariners several times. It not a hard job for anyone with a little mechanical knowledge.

1)Disconnect the gearshift linkage if it is up in the engine cowel. Alternatively it could be a splined connection possibly down near the gearbox, - for a splined connection the linkage shaft that runs down the leg rotates when changing gears and will part when the gearbox is removed at step 2).

2) Motor on tilt, remove the prop and split the leg just above the gearbox - usually 3 nuts . If there is a trimtab check there isnt a stud and nut under it. The lower leg should slide off.

3)Remove the pump cover, (note the lay of the impeller vanes - which direction they bend- a photograph can help ).

4)slide the impeller off - don't loose the key. If your lucky you may only have to replace the impeller but sometimes the stainless bottom plate and pump cover liner can be worn. If in doubt check with your friendly dealers mechanic.

5) Check if there should be small tefflon spacer washers either side of the impeller when at the dealers getting the impeller and any gaskets. These sometimes disappear with wear but can be important in maximising the life of the pump. Reinstall the key and slide the new impeller over it.

6) Smear rubber grease on the inside of the pump cover and gently push it on while rotating the drive shaft in the normal direction of rotation. This should lay the impeller vanes in the right direction mentioned in 3) above.

While you have the leg off you could try connecting a water hose to the water pump outlet tube in the leg (if appropriate adapters can be found) and see if you can get a flow out of your telltale.

7) Grease the shaft spline with an appropriate grease and also the water tube in the leg, and slide the lower leg back into place and bolt it on. This may take a little bit of jiggeling to line up the spline, the pump with the outlet tube and the gearshift linkage but generally isn't too difficult. If the gear linkage connection was splined it is important that the gear shifter and the gearbox is in neutral when they are joined.

8) Reconnect the gear linkage if it is in the cowel.

Note: always grease threads when reinstalling nuts. but stay clear of lubricants that contains metals such as copper coat or molydinum. I've heard they can cause corrosion and actually make parts grow together.

9) Connect up the flushing gear and give the motor a test run.

10) Stand back with a cold stubby and congratulate yourself on a job well done.

Willdoe

[KGW3]

Go to that fishing pictures site
Look at the subject water pump (1-20) by member Hoo's ur daddy.
He has put some pics together for his Yamma ha ha ha.

As it seems that you cant post links here...

Just cut and paste the link below into your browser and remove all spaces

Or use this link h t t p :/ /t i n y u r l . c o m /36pdz7 (http://#######.com/36pdz7)

w w w . m y f i s h i n g p i c t u r e s . c o m

[blu]

While you have got the box off IMO take it (the box) to your o/board mech and get a oil change.. if you drain out the old oil it is even cheaper but dont forget to take the oil bungs with you... this is what i done on my last impeller change and it only cost me 7$$ for the oil change..

[Luc]

Hi all,

Thanks for the info and links.

I'll start the dismantling job tommorow night so I can get all the bits & pieces on Saturday. Spoke to Sundown Marine and they have all the part I need for the impeller and service. Just under $100 unless anything else crops up.

Luc

[Luc]

New impeller installed (surprised at small size) and servicing done.:P

Took around 2 hours taking it nice and easy.

Test run tommorrow;D

The job was quite straightforward:

drain gear box (no trace of water)
disconnect gear selector, for yamis this is done by loosening the coupling just above the gearbox
undo 4 bolts holding bottom of leg and remove
undo 4 bolts to remove water pump cover
ease old impeller off & fit new one
reverse disassembly steps.Once again thanks for the advice.

Luc

This is the old impeller. The reason no water was coming through was due to the remains of one of the vanes being jammed in the pump outlet.

[KGW3]

Did you find the missing pieces of rubber? If not they may be be back to haunt you.Do you ever start that motor with no water going through it ? even for 10 seconds ?