Impeller shaft end play

[Venturian1]

The book says .002" - .023" end play, but how does one go about adjusting this? Thicker thrust bearing washer? The end play is measured without the nose cone installed, no?
Another thing.... On some impeller shafts, the part where the oil seal contacts the shaft is replaceable. It's like a collar that is pressed on. I don't see any such piece in the parts lists, so where to get one?

 

[gp1200x]

Different for different models but on a 951 155 pump for example the black housing cover controls the impeller shaft play. With cover installed and tightened the end play is then measured and if too large then you are supposed to change the anti-knock pusher. You can order new o-rings online I think at OSD marine or Ebay...or try to match at hardware store. I ordered some a month ago so I know you can get them. Make sure you oil the oring or it may catch and flatten a piece of it during install. I push the cone on squarely by hand completely and hold it there while screwing in the bolts. I always put some silicone on the other edge. I don't think you will have an end play issue unless you took the pump apart and did not reinstall it correctly. I only replaced my cone plunger once but I remove and clean it whenever I have it off....which isn't often. I do not change the pump oil every year like some. As long as mine is not leaking I may check it for water by removing the plug and sticking a thin blade down into it see what the fluid looks like. Never had any water intrusion so I only changed it like 3 times over 25 years.

 

[Venturian1]

Thanks for the info. I should have been more specific. I have a few 97's with the 717cc engine and the 140mm pump. Is the process still the same?
I do have one 2000 gti with a different species of pump... the nose cone is a larger diameter, and the impeller has rounded blades on the forward end, and the housing is different also. the center is a larger diameter than the other pumps I have, which seems like it would reduce the volume of water flowing through it. This pump, I recently had some water emulsified in the synthetic gear oil, so I replaced the shaft, bearings, thrust washer and seal, filed it up to the hole with oil, and on the 3rd day of usage, it locked up on me. I checked the oil, and there was none, only salt water, so I disassembled, the nose cone was full of black plastic, and the end of the shaft was down so far that i could barely clamp it in a vise, so I clamped a wrench in the vise that fit the shaft. The housing is now junk. It obviously got so hot it melted the plastic.
When I put the new parts in, I checked the end play, which was excessive, like .040" or more, and with the nosecone on there was none at all. It seemed to take the right amount of oil, I filled it with the pump clamped in a vise before installing it.
So, with the nosecone on the housing, with anti-rattle device installed, and impeller on the shaft, and before adding the oil, is the point where end play is measured?
And if there is none, as in my case, maybe I didn't get the anti rattle device in correctly?
Another baffling mystery to me, is, ..... when the impeller is tightened onto the shaft that's installed in the housing, and before installing the nose cone, checking shaft end play, when I push in on the impeller until it stops, what exactly is making the contact that stops it?
When riding the ski, acceleration is going to force the impeller in the forward direction, and the thrust bearing handles the load, no?
Then during the flush out process, I hear a random rattling noise. This is due to a worn out anti-rattle device, no? I always check end play after installing the nose cone, and there is always none at all, so how is this causing the rattling noise I hear when flushing?

 

[mikidymac]

Are you sure you set the bearings to the depth specified in the manual?
The large 150mm pumps don't have a spec for endplay as the pump cone anti rattle device is different. You have to make sure it releases and springs back when pressed through the fill hole with a pencil. If it is bound up you will have max preload and damage it.
And they all rattle with or without the "anti-rattle device".