thrust clearance

[4604me]

whats the deal on thrust clerance, how much is to much, and do you need that tight clerance for a mild lake cruser.

[Duane HTP]

Setting the pump up right is good for any boat. The norm for what you are doing is about .025".

[4604me]

so I install my new sholdered wear ring, and new A.T. impeller in my berk JC and I get .080 with no shims, so do I turn the shaft down .050, or cut the impeller to git a closer clerance. or am I missing somthing altogether.

[Duane HTP]

You cut the center of the impeller down some. To mess with the shaft will work, but makes it an odd duck from then on. Be sure to do it on a Bridgeport or such to keep the front of the impeller that goes against the shaft shoulder perpendicular to the leading edge of the impeller or it can wobble.

[inwo]

What is the tightest you can get by with? I might not have enough shims.
Dominator book says .015 is typical. This is in Dominator with wide wr.

[Squirtin Thunder]

Some folks run .010 !!! (Race Pumps)
I set-up most Lake and River pumps (Family boats) up at .030+

[sleekcrafter]

Some folks run .010 !!! (Race Pumps)
I set-up most Lake and River pumps (Family boats) up at .030+
Jim this is for a shouldered wearring, .025 is the spec for aluminum impellers, and less with Bronze or SS on race pumps. The Aluminum impeller will tend to grow and move foreward some.
Sleek

[Squirtin Thunder]

It is quite interesting that Berkeley had a habbit of setting the pumps up at .120+ from the factory. I have seen a few that have been over .250. But they have also lasted 30 plus years. With a new set-up .030+ is a good safe #, being that the thrust bearing will change thrust clearance on you as it breaks in.
If I am correct Daunes Ultimate wear ring is set at .020 on the bench and after break in it is most likely at .010, I was on meds when I talked to duane about this so I could be way wrong.

[4604me]

is this unusual to have to cut something to get the right clerance. I thought for sure I would have to shim because old wear ring had no shoulder.

[Squirtin Thunder]

Like I have said some pumps have come from Berkeley with .250+ thrust clearance. So no it is done regularly.

[inwo]

Now I think I'll have to pull mine out again. :(
Put in new ring and new impeller using the old shims, which were all I had. Did not change thrust bearing. I'll double check, but think I'm too tight. :cry:

[sleekcrafter]

This is from the AMT website on how to:
To remove old wear ring:
Use a propane torch. Place the flame on the brass ring go around in a circular motion until the insulator starts to melt. Grab the ring with a bent over screwdriver (90deg.) and pull out. Clean up wear ring bore.
Installation:
Place wear ring in freezer for four hours. Place insulator in suction bore. Spray with WD-40. Start wear ring by hand. Tap wear ring in using a wooden block and a mallet. You may use an old impeller but it may bottom out on the shaft before seating the ring.
Important:
Wear ring must be seated square in the bore with-in 0.004” side to side.
The axial clearance between the impeller and the impeller shoulder must be 0.025”-0.035” (check several places around the wear ring). Check again after the impeller nut has been tightened.
Torque impeller nut to 70 ft/lbs. Torque bowl bolts to 50 ft/lbs.
Sleek

[Squirtin Thunder]

And here are some videos to help if needed;
Berkeley Videos (http://www.cpperformance.com/TechTips/Berkeley-Rebuild/default.htm)

[TIMINATOR]

Isn't that manual copyright protected? TIMINATOR

[Squirtin Thunder]

which one ???
All the stuff I posted is right off the Berkeley web site !!! :cool:
You can click on the Berkeley link in my sig. for any Berk info needed.

[4604me]

Im still waiting for the ''rebuild the pump'' video

[Squirtin Thunder]

Im still waiting for the ''rebuild the pump'' video
Re-Building the Pump Video:
Coming Soon !!!
As hell freezes over !!! :cool:

[4604me]

To S.T. and Duane thanks for all the input, Im going to trim my impeller .055 that should bring me down to about .025 and Ill be good to go. Im going to try to post some pic of my boat if I can ever figure out how to do it. again thanks for all the info