Installed impeller having issues with priming

[Jason Steele]

Hi All,
I lost a drive belt while out and replaced it and got going again.. as we headed off again she was running a little hotter still pumping water so as soon as I could I replaced the impeller.. I have a 120 Ford Lees.. these are similar to the Ford Lehman I believe.
I followed the instructions on the install and re assembled however the pump doesn’t appear to be priming.. sea coach is open etc, I also let off the sea strainer etc but still no water.. my only though is that maybe the impeller is spinning on the shaft as it looks like there should be a spline.. none was present on removal or in the kit I had.. the channel has a pin a 3rd of the way.. I looked on line and people just slid the new one in after lubing.. any thoughts would be appreciated before I call in my marine mechanic....
Cheers

 

[GregBrannon]

I don't know your specific design, but my generator raw water pump has a key in a slot on the shaft that holds the impeller in place while the shaft spins. Removing the impeller usually dislodges the key. Once the key dropped into a place - the pump inlet our outlet, I forget which - that required significant effort to retrieve requiring many 4-letter words. Getting the impeller on with the key in place is also a frustrating exercise. I haven't done it enough to give any pointers and dread having to do it again.

If installed correctly, the pump should draw water. The suction generated by the raw water pumps I've experience with is impressive.

Greg.

 

[Jason Steele]

I don't know your specific design, but my generator raw water pump has a key in a slot on the shaft that holds the impeller in place while the shaft spins. Removing the impeller usually dislodges the key. Once the key dropped into a place - the pump inlet our outlet, I forget which - that required significant effort to retrieve requiring many 4-letter words. Getting the impeller on with the key in place is also a frustrating exercise. I haven't done it enough to give any pointers and dread having to do it again.

If installed correctly, the pump should draw water. The suction generated by the raw water pumps I've experience with is impressive.

Greg.

Hi Grey, yep your a spot on, the keys missing so I’ll need to find it.. should be fine now.
Thanks

 

[Irish Rambler]

G'day Jason, Good luck finding your key. You may find it helpful to use a 'wet & dry' vacuum up the water pipe to the heat exchanger to remove any broken pieces of impeller before you fit the new one. I find that a small tube of Vaseline handy to keep on the boat as its great for easing the new impeller into place, ideal when re-assembling hand pump toilets and coating battery terminals.

 

[Pack Mule]

I always bump the motor so keyway is at 12:00 . Then I put a dab of heavy wheel bearing grease in the slot to help hold the key in the slot while installing impeller.

 

[firehoser75]

Jason,
Good advice so far, especially the tip from Pack Mule (Marty). To make impeller removal go a bit easier, take the cover off the pump. Spray the inside liberally with WD40 and bump the engine (seacock closed of course ). If the keyway is not at 12:00, spray again and bump until it is. This "lubing and bumping" breaks the "bond like" connection that sometimes occurs as the impeller 'sticks" to the pump housing. The impeller should pull right out. Find any missing impeller pieces, as you will regret it if you don't. For lubing the new impeller, I recommend using either Glycerin or KY lube They will not damage the rubber at all and will provide good initial lubrication for the dry start.