Catalina 34

General Activities => Main Message Board => Topic started by: Ken Krawford on August 29, 2014, 12:51:19 PM

Title: Removing Shaft Coupling
Post by: Ken Krawford on August 29, 2014, 12:51:19 PM
While my boat is out of the water, I decided to change the bellows on the dripless shaft seal.  What a mistake !  I've spend the better part of 3 days trying to get the transmission coupling free from the shaft.  The shaft and coupling have no rust.  I applied PB Blaster to the coupling and into the 2 set screw holes several times.  Many taps with a regular and deadblow hammer did nothing.  I also heated the coupling with a heat gun and then a MAPP gas torch.  No Joy.  I then tried to "jack" it out using the arrangement similar to the one pictured below.   I was unable to use a 1" socket between the shaft and transmission as the key in the shaft was 1/4" proud of the shaft end.
It has been suggested that I will probably have to cut the shaft in order to get the coupling off.  I really don't want to do that but feel I'm out of options.  Any suggestions would be most welcome.

(https://farm4.staticflickr.com/3841/15072755811_d24264fce9_s.jpg) (https://flic.kr/p/oXVPbc)
Title: Re: Removing Shaft Coupling
Post by: KWKloeber on August 29, 2014, 01:05:39 PM
Ken,

Could you grind a slot into the socket using a cut-off wheel to allow for the Woodruff key?

Ken K
Title: Re: Removing Shaft Coupling
Post by: cmainprize on August 29, 2014, 01:07:28 PM
Sounds like you are the right path.  I would say keep doing more of the same.  Try looking at some different pullers from napa or somewhere that loans tools.  When I pulled mine I used a socket and the longer bolt method.  I would try that, leave the pressure on the shaft and then apply heat, then more pressure, PB, heat and so one.  Then throw the coupling away and get a flexable one from federal.
Title: Re: Removing Shaft Coupling
Post by: Indian Falls on August 29, 2014, 01:37:16 PM
You are on the right track to use the coupling halves to push the shaft out.  Don't use a socket the same diameter of the shaft. Put a nut or other thick item about 1/2" diameter, between coupling halves so you miss the keyway.  Keep in mind that the 4 bolts are small and meant to hold only the coupling halves together. Get hard cap screw's from the hardware store. Tighten them equally. If you can close the  coupling gap at all, it should go.  Then keep adding nuts or sockets to finish it off. If you want to use heat: Build up the tension. Put wet rag on the shaft. Heat the coupling shoulder with the torch aggressively but intermittently. Dont let the shaft to get hot too.
You might break the coupling ... If that happens, or it won't come off, I would cut the coupling not the shaft. A high speed air tool with a cutoff wheel will split the coupling easy.  You can't hammer anything without hurting the trans.  Let us know how you make out.
Title: Re: Removing Shaft Coupling
Post by: mainesail on August 29, 2014, 05:37:58 PM
Please remember that if you bend the gear box flange, very easy to do when it needs to be perfectly true, doing this it will cost you MULTIPLES what cutting the shaft does...
Title: Re: Removing Shaft Coupling
Post by: Ken Krawford on August 30, 2014, 03:58:11 AM
Thanks everyone for the input.  Mainsail, I have read your "How to" article and am aware of the pitfalls of bending the flange.  The tough decision is how much torque  can you put on a bolt before it starts to bend the flange?  Three cheers for a stuffing box. 
Title: Re: Removing Shaft Coupling
Post by: Gary on August 30, 2014, 04:11:27 AM
Ken,

From the image on the initial post it looks like a stuffing box to me, not a drip less seal??  The new gortex flax is great stuff. No adjustments, heat or leaks for some years in our stuffing box.

And, the transmission flange is a one piece part of the transmission drive shaft. If broken or bent the repair is a new transmission. Quite an expense....it happened to us in our 1986 because of PO breaking two ears on the flange and hiding it with the coupling. Yikes, costly!

Gary
Title: Re: Removing Shaft Coupling
Post by: Kyle Ewing on August 30, 2014, 04:36:04 AM
I used a steering wheel puller with excellent results.  See example at http://www.autozone.com/autozone/accessories/Tools-Garage-and-Equipment/Steering-Wheel-Puller/_/N-2652.

Shorten the "pushing" screw so it fits between tranny and coupler.  Bolt the base to the coupler and push out with a large wrench.

It was less than $20 at an auto parts store.  I spent hours trying what you're doing and it took me 5 minutes with the puller.



Title: Re: Removing Shaft Coupling
Post by: Ken Krawford on August 30, 2014, 05:29:03 AM
Kyle, that looks like it might be a winner.  When you say "shorten the pushing screw", do you mean cut it off?  I've got 3" threaded rod right now.  I see 6 bolts in the kit.  Will 4 of them align with the holes in the flange?
Title: Re: Removing Shaft Coupling
Post by: mainesail on August 30, 2014, 06:43:29 AM
Quote from: Ken Krawford on August 30, 2014, 03:58:11 AM
Thanks everyone for the input.  Mainsail, I have read your "How to" article and am aware of the pitfalls of bending the flange.  The tough decision is how much torque  can you put on a bolt before it starts to bend the flange?  Three cheers for a stuffing box. 

Not much and it needs to be very even. If it is not coming off with minimal torque it is beyond using the gear flange.

IF the boat has enough room the Buck Algonquin flange puller is what I use most...

(http://www.deepblueyachtsupply.com/images/productimages/couplingflangepuller.jpg)
Title: Re: Removing Shaft Coupling
Post by: Ken Juul on August 30, 2014, 11:12:42 PM
There is an old navy saying.....never use force, just get a bigger hammer!  Don't totally buy into it, but the idea is good.  Use the PB Blaster, use a puller or the longer bolt/socket/nut method.  Which ever method you use, put some tension on the coupling, then give it a couple good wacks with a hammer.  That is usually enough to break any corrosion bonds.  Also works well on props.