Bearing carrier threads

[Harker]

I picked up a used lower unit for my Navy seal motor to see if it changed performance over the pumpjet lower. I was trying to take it apart to check the gears and innards.I pulled the 1/4-20bolt through thethreads on one side andwas wondering what size I had to drill and tap the smooth hole that is now there. Can I just go to 5/16 or do I need to go bigger? Thanks, Lee

 

[R.Johnson]

Re: Bearing carrier threads

I'm not sure what bolt you are talking about, can you give us a better disciption?

 

[R.Johnson]

Re: Bearing carrier threads

I'm sorry about my first post, I see you said bearing carrier. Are we talking about a gearcase where the carrier bolt's, bolt to a inner retaining ring. If so! if you drilled it out larger, you would have to deal with the bolt head sealing surface.

 

[Harker]

Re: Bearing carrier threads

Whoops...It is one of the two holes used for pulling the carrier on the rearmost part of the carrier. When in operation, there are no bolts in the holes.

 

[R.Johnson]

Re: Bearing carrier threads

Were you able to get the carrier out? Is there enough material there to go to a 5/16-18 bolt?

 

[ledgefinder]

Re: Bearing carrier threads

When you strip & pull the threads on those holes, you're left with a hole diameter that's nearly ideal for the next size larger tap. The hole's just a hair tight, so take your time tapping the new one, but you'll end up with nice fuller-depth threads. "Taking your time" means using plenty of tapping oil, and frequently backing the tap out a few turns to clean it.

 

[Harker]

Re: Bearing carrier threads

Nope..the carrier didn't budge. I heated the casing with a propane torch too. I think 5/16 will be okay..just wondered if I had to go bigger to get good threads.

 

[Harker]

Re: Bearing carrier threads

Thanks, I'll get a 5/16x18 tap and give it a go.It will be fun with the propshaft in the way..but..everytime I screw something up it's in a place like that so I'm used to it.I was thinking of bending some hooks on a threaded rod and trying to hook under the cross thingies to pull it but they would probably straighten out.

 

[Harker]

Re: Bearing carrier threads

Got it all apart tonight. Tapped the stripped hole then drilled and tapped the other so I could use matching bolts for pulling. That carrier was a BEAR to get out. All the gears look great, now I guess I'll order a seal kit for it and put it back together...anything else I should check? What should I use to clean the housing and carrier with? It looks like someone used a gasket sealer on it..maybe the factory? Thanks for the help....Lee

 

[ledgefinder]

Re: Bearing carrier threads

Was the gearbox leaking before? <br /><br />After all that work, you won't believe how easy it goes back in. I'd use OMC Gasket Sealer on the OD of the two flanges of the carrier (even though there are also O-rings there), so it comes out easier next time. Also, O-rings and sealer on the 4 little bolts.

 

[Harker]

Re: Bearing carrier threads

There was no water in the oil...no rust on the gears or propshaft.One thing...I forgot about the spring and balls under the clutch dog and heard them hit the ceiling and walls..My shop is a mess from carving decoys so I am not even gonna try to find them.I may get new bearings for the drive shaft and carrier..just because...Plus I get to buy ANOTHER tool I'll only use once.