Prop Shaft Connection to VD Trans

wingless said:
Neither. As a life-long nutmegger I employed a BFH and imparted repeated impact force onto the shaft tip to break the joint.
XMSNHubs.jpg
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I can really relate to this statement.

One tool I will definatley have with me when separating this shaft from the coupler is my brass BFH, I am just concerned that there is not a lot of swing room.
 
tobnpr said:
FYI the couplers are always fitted/machined to match the taper of of the shaft, so changing either one requires sending both to the machine shop.
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Yes they are, don't change the taper.

Mine were repaired by knocking the high spots down to fix the fit problem. On the problem coupling at the narrow end, near the nut, there was an internal lip. That image is out-of-focus and not useful.

That lip caused a two ring contact, one at the lip and one further down, but not all the way around.

This image shows the good fitting port side, w/ uniform discoloration on the surface and the stuck starboard side, w/ a partial contact ring.

They now fit together well, w/ great contact surfaces.

ShaftCouplingTaper.jpg
 
Well removing my hubs from the shafts has proven to be a major PITA. I tried my harmonic ballancer puller with two long bolts but I just don't have the room to get much leverage as the distance from the end of the shaft to the foward bulkhead of the ER is 4 inches. I tried my slide hammer using a external three finger puller behind some large washers clamped between two prop nuts and neither side will budge. I also tried repeated blows from my brass BFH but again there is little swing room. I am thinking that this is a two man job, with one guy in the ER heating the hub and the other guy on the slide hammer trying to pull it out. I am thinking that a propane or even MAPP hand torch is not going to be enough to heat up this large mass of metal and that I need to give this job to the marina so they can use acetylene, not to mention deal with the concerns about heating this in the engine room, the damn fuel lines pass right along side these couplers. Any one have any other advice for me before I throw in the towel on trying to do this myself?
 
Hey Jon, sorry to hear about the road block you got there. Since I never this this type of repair I can't offer any good advice, but I can offer my help being the 2nd guy in the ER. If you get enough info and have a game plan, let me know and we'll schedule the trip.

Cheers,
Alex.
 
Thanks for the offer Alex, I will let you know what I end up doing. I want to discuss it with the service manager and they are closed until tomorrow. I think I might leave the to them, I am not too keen on working with an open flame in the engine room.... the yard has insurance.
 
I just spoke with the master machinist husband of one of my employees to get his advice on this situation. He said that he thinks that even heating with a hand held propane torch should eventually open up the hub bore by 3 or 4 thousanth's and allow it to be be removed from the shaft. I am still very concerned about using an open flame in the ER.
 
I have tried this in the past with success, although I'm not sure exactly how much room you have.

Try heating the hub uniformly with a torch. After the hub is really hot, use a piece of ice or compressed keyboard cleaner spray to quickly cool the shaft (not the hub). This may allow the shaft to contract enough to separate them.

Doug
 
I'm sorry that those hubs don't want to separate. I have mixed emotions when this happens. Sometimes depending on what needs to be done, it is just easier to cut the shafts and replace them. It is purely a time trade off of what your time is worth fighting with these things and danger of taking a oxygen/acetylene torch in to a confined space with fuel tanks.

Before I took a torch into the engine room on your boat....I would cut them, replace the shafts, hubs and cutlass bearings. That's just me.

-John
 
mrsrobinson said:
This shaft was replaced 7 months ago from the log that hit us. Our mechanic told us the seal looked good when he did the replacement. Can you tell by looking at it, on land, I assume with the shaft out, that it looked good? I did tell him about the water on that side of the boat after the shaft install and he said the shaft seal was in good shape, not leaking.

The water was present before/after the shaft replacement so nothing about the replacement made it better/worse.
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Greg,

Depending on who you talk to, shaft seal replacement should be performed every time the shaft is removed. I questioned the place that worked on Saint Max in 2007. It's their SOP because of the possibility of nicking a seal on shaft removal. If you are getting water under the engine, check the seal area while the boat is underway. It may be a bad seal. It may be a loose clamp. As stated earlier, if it is a seal, keep an eye on it until you have to haul. The crossover is an easy do for very very little money.

HTH
 
Before I took a torch into the engine room on your boat....I would cut them, replace the shafts, hubs and cutlass bearings. That's just me.

Yea while I think heat is the answer I have decided that I dont plan on being the "heater". I will call the yard tomorrow and see if they can put two guys on it for an hour or two to see if they can get them off before I cut the shafts and start over.
 
Thanks for the info. I have authorized the yard to spend up to 4 hours of labor to try and get them off. I will see how they make out before proceeding.
 
What's that hydro-puller go for? More than $420 I'd imagine. :-(
 
You know me Ron, if it was that cheap I would be buying one, looks like a very cool tool.
 
Update on this saga, I got an email from the yard on Wed night telling me that it took a technician 2.5 hours to remove the hubs and that they were off and waiting for me to pick up. I dont know how they did it and I have not driven the 1 hour one way to go get them but I am glad that I am past this issue, and on to the next. So here is a dumb question for those of you that have been here and done this. The hubs are bolted to the output flange of the transmissions using four 7/16" x 1.5" fine thread grade 7 bolts on each hub. Yes, not grade 8 but grade 7 according to this guidance: http://www.americanfastener.com/technical/grade_markings_steel.asp

Some of the heads of the bolts and the nuts are kind of getting rounding off so I want to replace these bolts and nuts. Of course finding grade 8 hardware is a lot easier than grade 7. Can you see any reason I can not just go with grade 8 here?
 
J Levine said:
Update on this saga, I got an email from the yard on Wed night telling me that it took a technician 2.5 hours to remove the hubs and that they were off and waiting for me to pick up. I dont know how they did it and I have not driven the 1 hour one way to go get them but I am glad that I am past this issue, and on to the next. So here is a dumb question for those of you that have been here and done this. The hubs are bolted to the output flange of the transmissions using four 7/16" x 1.5" fine thread grade 7 bolts on each hub. Yes, not grade 8 but grade 7 according to this guidance: http://www.americanfastener.com/technical/grade_markings_steel.asp

Some of the heads of the bolts and the nuts are kind of getting rounding off so I want to replace these bolts and nuts. Of course finding grade 8 hardware is a lot easier than grade 7. Can you see any reason I can not just go with grade 8 here?
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Glad to hear you got it taken care of. Grade 8 should be fine as the only difference between grade 7 and grade 8 is the fact that the tensile and yield properties are much greater. Tension is important to keep the hubs in a locked position, otherwise the bolts will be subjected to shear. Grade 7 or 8 bolts aren't made to stand up to shear applications.

Doug
 
Glad they got your hubs off easily. It is said that you should reinstall each hub to the shaft it came off of. Also, clean enough of the shaft so that it slides through the cutlass bearing in the strut without damaging the cutlass bearing when you back the shaft out.

Check the instructions on the seals. They may be installed dry with no lube.

Good luck.
 
I am going to completly remove the shafts and take them to my prop shop to have them inspected. I plan on taking the hubs and the props to them at the same time so that the bores can be clean and adjusted if needed. I have had very good luck over the years using Merc "Special Lube 101" on the props to make them easier to remove each fall so I will use the same on the hubs when I put them back on. As far as the fastners, I looked at HD yesterday and what they are selling as grade 8 is marked the same way as what I found on my bolts so who knows. Of course HD does not stock the fine thread stuff so I will have to go somewhere else to get them, it should not be too hard to find them. I still need to order the seals so I probably wont get arround to putting all of this back together until after the holidays at the earliest.
 
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