installing impellers

[Steve]

I have tried several means of installing impellers. piston ring compressors, fishing line wound around the impeller, and just trying to squeeze it in by hand. What works best for me is one or two nylon cable ties, you put them on and turn the fins in the right direction and tighten the*cable tie*compressing the impeller then lube it up with some soapy water and slide it right on in usually the ties will come off as the impeller goes in.
you may want to try it next time you have an impeller to change, it works well for me. To remove them I bought a (expensive) puller by Jabsco it cost plenty but works great.
Steve

 

[Baker]

I will have to say....and I might get slapped down for this one....but it does not matter which way the vanes go when installing an impellor...just stick the thing in there. Does one really think the vanes are gonna remain in the position in which they were installed? They are rubber and the friction of the casing will cause them to go into position. The minute the shaft begins to rotate they will orient themselves in the direction of rotation.

 

[Marin]

John--- You are right, but I've been advised to always rotate them in the direction they're going to be turning, especially with large, stiff impellers. You are correct that no matter how the vanes are oriented they will orient themselves properly as soon as the impeller starts to turn. But starting them out bent the right way is one less "stress" the blades will be subjected to. I've also been advised by the mechanics that taught me that slathering an impeller with grease or vaseline makes it a lot easier to work it into the chamber. I've found this to be true.

 

[Keith]

The wire tie trick is a neat idea... I've used hose clamps before as well. I was told not to use any kind of petroleum grease on them... attacks the rubber? I always spray mine with silicone spray. Also liberally grease the shaft with silicone plumber's grease or Tef-Gel to facilitate removal later.

And yea, that impeller puller is worth it's weight in gold if one is stuck!

 

[Jim Spence]

I use the same method that Steve does. I use the 1/4" wide tie wrap with the blades turned in the correct direction. I recently replaced both impellers on my 6-92 detroits. This was the first time I used silicon grease. I had been using vasoline. What a difference it made getting the impellers in. Next time I pull them I'm going to put some silicone in a couple of places in the housing, spin the engine over with the stop button down and see if they come out easier.

I only have 8 inches between the housing cover and a 5 inch exhaust to get them out so I have not used any of the commercial tools because in the catalogs they look too long. I highly recommend the silicone grease.

 

[FF]

Well I no longer use impellers , but for northern folks the most important point is to yank them for the winter , so the rubber\ doesn't take a set.

Good practice , as runs thru thin sandy or turbulent water can wear them out in 50-100 hours.

They were designed to pump mostly clean water , to run them in the shallows is a high risk.

FF

 

[Dougcole]

Have you seen the speedseal cover? I've been thinking of getting one of these for my stb water pump, which is a bear to reach.

http://www.speedseal.com/speedseal.html

 

[Marin]

Doug--- Several folks on the Grand Banks owners group with Lehmans have installed these and from what they say they are very happy with them.

 

[Keith]

I put a Speedseal on my Lehman 135 and love it. I keep a little kit with a pair of pliers, silicone plumbers grease, new impeller and impeller puller in the engine room. I bet I could change that thing out in 10 minutes if I was motivated! Like underway in a shipping lane. However, I change the impeller pretty often anyway, just so that doesn't happen. I did get a spare O ring for it, but have never had to use it.

 

[Dougcole]

My only hesitation on the speed seal is the access to the impeler after the cover is off. Right now, the only way to get the cover off is to remove the whole water pump, I have to lie (lay, lie, "woman, wilt thou lay with me?" whatever) on top of the engine to reach that side. No fun.
The speed seal would solve that, but I'm still not sure about the impeler removal with the pump attached, as I've never tried it.

Doug