Dominator impeller help

[inwo]

I haven't kept up with jet pump repair since 1972. :)
I've had a AA impeller/ring sitting around for years and thought I would replace the A impeller in my 18 year old Dominator.
Thought they were all the same. Turns out new AA impeller is about a quarter inch longer in the wear ring shoulder. Almost busted the housing before I noticed. Went way to far before I noticed impeller hit wear ring insulator before bottoming on shaft shoulder.
What have I got ? How can I make this work?

[flat broke]

Dominator made pumps with a 1" and .750" wear skirt. Sounds like your trying to put 1" parts into a .750" setup. You could purchase the proper .750" wear ring (if that is actually what the issue is) or possibly (and I'd check with your local pump guru of choice on this) cut the wear skirt down to the .750" surface that should fix your problem.
I'm sure some more knowledgable/helpful folks will post up in no time.
Chris

[Squirtin Thunder]

I would send it to Jack @ (MPD) Marine Performance Design in Costa Masa, Tell him what you have and he will fix you up. Jack is a impeller god.
Marine Performance Designs
1760 Monrovia Street. Unit A-7
Costa Mesa, California 92627
Contact : Jack McClure
Phone : (949) 631-2040
e-mail : jmcclure@pacbell.net
www : http://home.pacbell.net/jmcclure

[Duane HTP]

INOW, Dominator made an early model and a late model pump, with the .750" wear ring, it could be either one. The major difference is the outside diameter of the wear ring itself. If it's the early model, you have to stay with an early style wear ring. They all used a .750" ring. The impeller can be cut to fit that ring. If it happens to be the later style, then you can buy the later wear ring to fit and use the impeller with the 1" surface. I've been a warehouse distributor for Dominator ever since they started, basically and have the information to tell which it is. If you want, you can send the serial number of the pump and I'll look it up and let you know what you have. (the number should be right on top of the thrust bearing on a tag).
doblander@hi-techperformance.com

[inwo]

Thanks guys!
Here's what I have.
Shoulder on wear ring is 1". Surface for wear ring/insulator in pump is 1".
1/4" of the pump surface is used up by the shoulder on the insulator and 3/4" by the wear ring.
The impeller will only go in 3/4" til it meets the insulator shoulder.
The pump is MB12S Ser # B14441 12-87
Seems as if there was no wear ring shoulder it would fit.
Another problem is wear ring clearance. This is the ring (brass?) and insulator that came with impeller, but it seems tight. ie. zero clearance.
Maybe my whole problem is wrong wear ring?

[Duane HTP]

It sounds as if you have the wrong ring for the impeller. Also, see if the outside diameter of the new ring is the same size as the outside diameter of the old ring. Then there should be from .020 to .025" (side) clearance between the new ring and the impeller.

[inwo]

I'll have to pull the ring as it is installed. It fit nice. Tapped in easily.
Heat is the only way to remove ring, right? Sacrificing the insulator.
With correct parts (ring) , do you think the 1" impeller will fit?
The ring was a slip fit before install. Now it is zero clearance.

[Duane HTP]

do you think the 1" impeller will fit?
Only if it ends up being the new style pump. Otherwise it will have to be cut to fit.

[BigBlockBaja]

Only if it ends up being the new style pump. Otherwise it will have to be cut to fit.
I think that is what you told me to do Duane when I was putting in that Agressor AA Impellor in the Berkeley f pump, right? Same senario, different brand pump?

[Duane HTP]

I believe the issue on your impeller was fitting an ATJ impeller into an F Series Berkeley which requires that you cut off the stuffer ring on the back of the impeller. On his deal, he may have to cut the front .250" off of the leading edge of the impeller to make it fit the older style .750" wear ring.

[inwo]

Duane
Emailed you also.
It looks like I have the new style pump. All I should need is the right w/r.
The pump bore is 7.7xx and 1" deep.
The impellor is new with 1" surface, so a stock w/r should be fine.
I dry fit the pump, shaft, and impeller with no w/r and clay to check fit.
It has about 1/8"+ clearance front and back with no shaft shims.
It seems the ins/w/r combo I tried was made for a 3/4" impellor as it had a 1/4" lip on it to hold the ring out 1'4".
Also, this ring will not work anyway, as it has only .008" clearance.
tnx
Dave

[Duane HTP]

I read your email. You've got it figured out now.