Lower rudder bearing housing replacement

[Dacron 20]

I need to replace a worn out and pitted Jefa bearing housing from a 36.7.  Its an aluminum donut glassed inside the bottom of the rudder tube.  And for clarity - i’m talking about the bit the bearing ball slips into, not just servicing the bearings.

Any tips on the approach and methodology would be appreciated.  For example, I could very easily (i think) cut the whole rudder tube out from the inside of the boat and the bearing housing might come with it, and I could then just sacrifice 4” off the bottom end and reglass the new bearing housing back into the boat.  Or I could attempt something much more surgical from the outside in - try and drill it out or something.  Or, from inside the tube I could just take a grinder and grind the alu to dust, leaving the stern tube ready to receive the new - not sure how realistic of a solution that last idea is?

How would the pro’s approach this?  Thanks in advance.

[Shenanigan77 5]

I'm not a pro and I'm not personally familiar with your bearing installation, so I feel fully qualified to answer your question.  I did lose several days of my life pulling a Harken rudder bearing with an aluminum outer housing from an Express 37.

First, I think it's very unlikely the lower bearing housing is glassed into the tube.  It was likely originally installed with an adhesive. However, if the boat is used in salt water, it's nearly guaranteed the aluminum corroded and swelled over the years, so basically the same thing. You'll never drive it out.

I was able to make several linear cuts in my housing using a sawzall from below.  I worked very slowly and avoided damaging the tube.  Then I was able to pry out the bearing housing segments.

If by some chance this approach works in your case 1) I'm pleased and 2) I'm as surprised as you are.

 

[slug zitski 575]

4 hours ago, Dacron said:

I need to replace a worn out and pitted Jefa bearing housing from a 36.7.  Its an aluminum donut glassed inside the bottom of the rudder tube.  And for clarity - i’m talking about the bit the bearing ball slips into, not just servicing the bearings.

Any tips on the approach and methodology would be appreciated.  For example, I could very easily (i think) cut the whole rudder tube out from the inside of the boat and the bearing housing might come with it, and I could then just sacrifice 4” off the bottom end and reglass the new bearing housing back into the boat.  Or I could attempt something much more surgical from the outside in - try and drill it out or something.  Or, from inside the tube I could just take a grinder and grind the alu to dust, leaving the stern tube ready to receive the new - not sure how realistic of a solution that last idea is?

How would the pro’s approach this?  Thanks in advance.

If the Jefa is an aluminum socket glassed  into the hull,  Use the correct size hole saw to cut it out 

double hole saw technique ...or a wood bung with a pilot hole drilled in the center as s hole saw guide 

[longy 847]

I'd cut slots in it length wise - I think hole saws wobble too much. Pretty certain sleeve is stuck into GRP tube with some caulking. Call PYI?

[slug zitski 575]

The aluminum tube , or fiberglass tube is normally bonded with sika or 5200

just knock it off , you might be able to clean it up and use again 

good idea to purchase a new tube and gaiter with the new bearing 

A hole saw works well , clean hole .. with a guide ... second inside hole saw guide or a tapered wood bung pounded into the bearing  housing with a centerline pilot  hold drilled into it 

hole saws come in many sizes ... if your lucky the hole saw ID matches the bearing OD 

fiberglass is soft , cuts easy with a sharp hole saw 

turn the saw very slowly , 

Use a powerful drill , be careful that the hole saw doesn’t bind .... the drill , saw  will break your arm , bust out some teeth or three stooges you off the ladder 

when choosing a new bearing best to go with a non metallic Jefa if it’s suitable for your rudder 

cutting out corroded aluminum every ten years is a pain in the ass 

[DDW 1,069]

You may be able to heat it with a torch and then use a slide hammer to yank it out (or drive it from the top). 

[Haligonian Winterr 57]

If you're going to buy new, just cut the housing into segments. Make sure the cuts are tapered out so they don't lock in the segment you've just released. Even screwing up a few cuts by going to deep is guaranteed to be less damage to the hull/sleeve than using a hole saw.

 

Make sure you have new part specs in hand before going to town.

 

HW

[Autonomous 1,232]

8 hours ago, DDW said:

You may be able to heat it with a torch and then use a slide hammer to yank it out (or drive it from the top). 

I suspect dry ice would be more helpful. 

[gewoon ik 83]

8 minutes ago, Autonomous said:

I suspect dry ice would be more helpful. 

but it is harder to put the boat in fire.

[DDW 1,069]

38 minutes ago, Autonomous said:

I suspect dry ice would be more helpful. 

The heat is to break the glue bond. Press fits of an aluminum part into a fiberglass tube are never very tight - the aluminum is far stiffer than the fiberglass. If epoxied in you need about 200 deg, polyester maybe 300. Sika or 3M it won't just give up but will soften, in that case you need a constant pull, not a slide hammer or driver.

[Autonomous 1,232]

Understood. 

[Lex Teredo 383]

People say 5200 is permanent but a gently wielded propane torch and a heavy push / pull from a big boy will bust loose a through hull. [<- Voice of Actual Experience.] 

The wider body of a rudder bearing secured with 5200 or similar tenacious adhesive is likely prone to getting a little sideways and binding up a little as it's removed so it would make sense to keep it as straight as possible (both on the horizontal and vertical axis) and pull it out carefully, in line with the tube.  Slug's idea of a bung (to help keep the pulling effort straight and even) sounds smart here too...   [<- SWAG - Scientifical Wild Ass Guess. But not wholly uninformed.]

[gkny 26]

I ended up cutting  the rudder tube above where it joined the hull and then using a jigsaw to cut out a section of the aluminum housing as others have described.  I used some Centek exhaust tubing to replace the rudder tube.  It was relatively inexpensive and not to hard to fiberglass in.  Depending on the sizes you may be able

 

Centek Industries, Inc. • 116 Plantation Oak Drive, Thomasville, GA 31792 • 229.228.7653
www.centekindustries.com4” Vernatube™ Exhaust Tubing
Part # 1100504-1METER Data Sheet
Vernatube™ is a corrosion-resistant high temperature exhaust tubing
designed specifically to minimize exhaust gas and cooling water flow
restrictions on wet exhaust systems. Precise outside diameters facil-
itate perfect connections between sections of the tubing and flexible
joints or hoses

[steele 195]

I dealt with this last year, the aluminum had swelled and corroded jamming the bearing. It was cut out in pieces with a recipricating saw from below without damaging the  rudder tube. As you can see the bearing also had to be cut out, it should be removable by hand but was stuck in place by the failing aluminum housing.

It was replaced by a non metalic set up from Jefa, I would strongly recommend you contact PYI, there were very helpful with advice and sourcing the proper size.