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Shaft Coupling Bolts

Posted: Aug 20th, '16, 08:43
by Joseph Fikentscher
Yesterday while running ou to the fleet about three mile from the inlet, the port engine suddenly revved up high. Immediately backed off on both engines. The port engine had no forward or reverse. hat ended fishing and I turned back and came home on the starboard engine.

At the dock, I got in the water to check if I lost a prop or wrapprd some rope. Nothing. Prop turned.

Checked the V-Drive and all of the bolts holding the shaft couplings together were sheared off.

So, my question. I need to get the Trans coulpling off since the threaded ends of the bolts are still in their holes. Can this be done without hauling the boat? I assume I put it in gear to stop the rotating so I can remove the nut holding the coupling on.I can move the shaft back a few inches to have some room. Not sure if its enough. And why did this happen? Did the PO use the wrong bolts at some time? Is there a hardened bolt that should be used?

Re: Shaft Coupling Bolts

Posted: Aug 20th, '16, 22:26
by scenarioL113
I dont know why it happened. Possibly the bolts loosened up? The coupler bolts are fine threaded and specific for this purpose. Should have lockwashers as well. Not sure if hardened like grade 8. I forget.

Getting the shaft coupler off will probably not be easy. Especially if it has been on for a long time. Since the threaded ends are still on place you cant make the couplers into their own removal tool. Otherwise you could put a spacer between the couplers and then Tighten the bolts back up evenly. Kind of like a "puller".

Def soak it as soon as possible with pb blaster or other penetrating oil.

Last time i tried to remove a coupler i had to cut the shaft.

Sorry if everything i am telling you is negative. You may get lucky though. I know V Drives and its tight to work under there.

Hopefully someone with more experience can give you some advice.

Re: Shaft Coupling Bolts

Posted: Aug 20th, '16, 22:59
by Tony Meola
Joe

You can keep the shaft from turning on you by using a pipe wrench or a large clamp. If you use a pipe wrench, put some tape around the shaft so you don't chew it up. The shaft will spin until the handle of the wrench wedges against the hull.

The shaft should slide back. But and there has to be a but, if you painted the shaft, the paint trying to slide through a cutlass bearing could give you guys.

Try soaking every thing in penetrating oil or a mixture of tranny fluid and mineral spirits. If you are careful you can also apply heat to the coupler.

I take it that the bolt is snapped off flush. I would say that there had to be some play in there that allowed the coupling to stress the bolt. Hitting something could do this also.

Re: Shaft Coupling Bolts

Posted: Aug 21st, '16, 21:57
by scot
An old boat mechanic taught me to put a washer, spacer in front of the shaft to keep it from being directly against the transmission flange (inside the companion flange). The reason is that the shaft can flare a few thousandths over the years from pressing against the transmission flange. The slight flare makes the shaft coupling (companion flange) extremely difficult to remove! I hope you don't run into this scenario.

Once you do get it off, when you go back together place a washer or some type of small spacer at the end of the shaft. Sorry, I know hind sight tricks and methods sucks.

Good luck.

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 08:28
by Joseph Fikentscher
Here is a picture. The bolt stems are in the trans coupling. Need to remove them to put in new bolts. Obviously not much room to work. Maybe enough protruding for vice grips? I am going to buy a new pair of Vice Grips today, need a good edge to grab the bolt stem.

Image

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 08:48
by Navatech
  1. Why aren't these bolts not soaking in some penetrating oil?!...
  2. Make sure they're real (as in the brand) ViseGrip...
  3. A hammer and a sharp cold chisel might come in handy...
  4. Semi worst case, it might be possible to get in there with an angled drill... If so, drilling and using a bolt extractor might be possible...
  5. Worst case is that you have to pull the shaft and get the coupling of the gear at which point you can take the coupling to a machine shop for extraction of the bolts...
Last but not least, don't give up if the vise grips slip... Try using the hammer and chisel to create 2 flat faces for the vise grips to grab a hold on... A metal file might be helpful to for this job...

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 09:01
by Rawleigh
Wow, you really do have a space problem!! Can the bellows compress anymore? I don't know how you will get that off without pulling the shaft! I have used a socket for a spacer between the couplings with longer bolts to remove them before.

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 09:34
by Carl
Dumbest design...V-Drives are great, on paper, great to make most of space but tough as hell to work on after a few years sitting in a bilge.


Just keep in mind...broke end of bolts may have threads in bad shape, stretched, mauled etc.....you do not want to force bad threads through the tapped hole. Doing so you may wind up jamming bolt and screwing up couplings threads. So if going in that direction (removing from back) maybe grind fouled remaining threads off front face...just don't force.

If you can center punch and drill bolt from back side...chances are good the bolt will grab on drill and screw right out the front. But you have to get center and drill straight. Could also work with LH drill from front of face...or easy out.

If using vise grips on the back of the bolt...if you mangle that end...you may have tough time pushing or pulling thru tapped hole if you need to go the other way.


I do not know your setup...hopefully you have the room to attack the job in a better way then I have seen in other setups. Usually, I see customers mechanics pull the tranny coupling as they cannot get in there and do anything more then butcher the thing.

As Navatec said...Penetrating Oil.
Penetrating oil is your friend.

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 10:03
by Joseph Fikentscher
Penetrating oil going on today. Very limited space, I have to work by feel because I can't see anything down there. Access is through this small hatch, about 12 inches square.

Image

I had to hold the camera under the trans and get the pics.

Image

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 10:09
by Navatech
Damn... I didn't realize that access sucked that much... That's NOT going to be fun...

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 11:58
by Carl
I hope they are loose...

If loose and you cannot grip to crank out with Vice Grips...another option may be to try with a Dremel and cutoff wheel. Cut a slot into face then use a screwdriver to run it through.

Still tough doing blind....have any small kids around?

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 13:43
by Joseph Fikentscher
Good idea Carl!

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 13:47
by Joseph Fikentscher
I'm also going to lay a mirror in the bilge to help see.

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 14:29
by Carl
Joseph Fikentscher wrote:I'm also going to lay a mirror in the bilge to help see.

I feel for you...hope they screw right out.


...mirror works.

...but if you know anybody that has an inspection camera you can borrow...they can be real helpful working in spots where its either your hands in there or you can take a peak...but not both.

Re: Shaft Coupling Bolts

Posted: Aug 22nd, '16, 22:56
by Tony Meola
Joel

Not familiar with the 25's deck, but if it comes out easy enough. I would pull it. On my 31 if I had that job, spending an hour pulling the deck would be well worth it.

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 06:09
by White Bear
There is no chance that you will be able to remove all of the you bolts using the ViseGrip approach, particularly if you are working blind. Save yourself much time and frustration by opening up the working area.

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 08:08
by Joseph Fikentscher
The 25's deck is really not easily removable. It is bonded to the hull. Kind of like a unibody approach. Vberths to stern all one piece.

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 08:48
by CamB25
Ouch! Now I know why you asked about outboards!

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 09:45
by Rawleigh
Crap! That sucks! How about access to remove the transmission? Would you have to pull the engine too?

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 10:01
by Joseph Fikentscher
Engine and trans have to come out. Really don't want to haul her for that.

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 15:04
by Rawleigh
I see the shaft coupling is a split type. Any chance of getting that off? I doubt the transmission coupling is split as well is it?

Heat the bolt stubs up good and apply bees wax to them. As it cools it will draw it in. I use a toilet bowl seal for my wax.

Re: Shaft Coupling Bolts

Posted: Aug 23rd, '16, 23:06
by Tony Meola
Rawleigh wrote:I see the shaft coupling is a split type. Any chance of getting that off? I doubt the transmission coupling is split as well is it?

Heat the bolt stubs up good and apply bees wax to them. As it cools it will draw it in. I use a toilet bowl seal for my wax.
Never heard of that trick. Does it work better than pb blaster?

Re: Shaft Coupling Bolts

Posted: Aug 24th, '16, 09:10
by Rawleigh
It did on a small bulldozer I rebuilt! How much is the heating and how much is the wax I don't know.

Re: Shaft Coupling Bolts

Posted: Aug 24th, '16, 21:27
by Tony Meola
Learn something new every day. Was this your idea?

Re: Shaft Coupling Bolts

Posted: Aug 25th, '16, 09:08
by Joseph Fikentscher
Carl,

Your idea of using the Dremel to notch the bolt end to use a screwdriver works, except you need to use a right angle screwdriver and with the limited room it is really hard to get any pressure on the bolt. After about three hours I have one bolt about halfway out and my fingers are a mess.

I'm going to cut off with a sawzall, the bolt I am working on, between the flanges so I can raise the trans/motor assembly. Looks like I can get about 4 inches. Might be enough to partially clear the shaft flange and possibly get a drill in there to use the easyout. I removed the front engine mounting bolts yesterday and will loosen the rear bolts today. Then using a lever (2x4) I plan to raise the front of the engine and support it. Then hopefully I will have more room.

Rawleigh.

Heated and waxed. We'll see how it works.

Re: Shaft Coupling Bolts

Posted: Aug 25th, '16, 11:00
by Rawleigh
Joe: Sears used to have some small ratcheting 90 degree screwdrivers that might help.

Re: Shaft Coupling Bolts

Posted: Aug 25th, '16, 11:33
by Carl
Remind me to never complain about working on my boat...

If you have bolt turned in a couple turns from back of flange...can't you use Vise Grips from front flange side to crank out the rest of the way?

Re: Shaft Coupling Bolts

Posted: Aug 25th, '16, 11:44
by Joseph Fikentscher
Rawleigh,

Yes That's what I am using.

Carl,

Possibly, but the shaft isn't moving back because in my wisdom I used antifouling paint, Possibly I can move the engine forward about an inch or two. That's all the room available before the bulkhead.

Re: Shaft Coupling Bolts

Posted: Aug 25th, '16, 14:57
by Carl
Joseph Fikentscher wrote:Rawleigh,

Yes That's what I am using.

Carl,

Possibly, but the shaft isn't moving back because in my wisdom I used antifouling paint, Possibly I can move the engine forward about an inch or two. That's all the room available before the bulkhead.


Oyyy...hindsight always 20/20.

Feel like taking a dip and scraping a little shaft paint?

Re: Shaft Coupling Bolts

Posted: Aug 25th, '16, 16:02
by Joseph Fikentscher
Not sure if this was the right way to go but I used a screwdriver and separated the flanges, moving the shaft back. Then used channel locks. Got 3 of the 4 out. Last one doesn't want to turn either way. Of course.
I wonder if the engine has settled over the years. There is wood between the motor mount and the steel runner attached to the stringer. The old Previous Owner probably didn't want to replace the motor mounts. Although it is the same on both port and starboard engines. The line-up with the shaft is a little off (engine/Trans about 1/8 low). I'm going to replace the wood while i'm in there for this season and next season the motor mounts.

Re: Shaft Coupling Bolts

Posted: Aug 26th, '16, 10:46
by Joseph Fikentscher
Well, that was an ordeal. Finally got it back together this morning. Seems to be running ok. Thanks guys for all the suggestions. It really helped, both with knowledge and also just knowing that the faithful are there. It really helps.

Re: Shaft Coupling Bolts

Posted: Aug 26th, '16, 11:29
by Carl
Great news, happy you didn't have to pull motor and/or boat to deal with it!

Let the season continue!



I'll agree, this is a great little sandbox that the Captain put together for us.
Help in all forms...

Re: Shaft Coupling Bolts

Posted: Aug 26th, '16, 22:35
by Tony Meola
Good to hear. It can be frustrating at times.

Re: Shaft Coupling Bolts

Posted: Aug 26th, '16, 22:35
by Tony Meola
Good to hear. It can be frustrating at times.

Re: Shaft Coupling Bolts

Posted: Aug 29th, '16, 09:49
by Rawleigh
Wow, that had to suck! Glad you got it done though.

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 09:43
by Joseph Fikentscher
Well, here I go again. Same side, same problem. The shaft coupling bolts sheared off again. This time I was only going about 6 knots around 1200 rpm. Could only get two of the bolts out. the other two broke flush at the trans coupler.

As before, no room to work. Had to cut the deck a bit to raise the engine banditry to take out the v-drive. Removed the 6 bolts and started to ease the shaft out of the trans. Was surprised at how long the shaft was.

After mush wrangling I got the v-drive off, and will be able to get to the broken bolts easily. But reinstalling the v-drive will be very hard as is t=is quits heavy and it was a bit if a squeeze to get it out. And ill have to get the splines aligned. UGH.

Going to try to separate the middle section with the shaft to get that back on first.

Fingers crossed.

But not sure why the bolts keep shearing off. Doesn't seem to be any play in the coupler shaft on the v-drive so the bearings are ok. But something is wrong. I can't keep doing this every three years. Or again a week after I finish this repair. This is not fun!

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 10:31
by Rawleigh
I think you ought to replace the coupling if you can. Something is obviously wrong. Did you put loctite on the threads when you reassembled it? Rawleigh

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 10:48
by Joseph Fikentscher
No, I did not use Loctite. Just the bolts and lock washers.

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 11:18
by Carl
Wait a second...why is the trans coupling threaded?

Maybe we went through this last time, but shaft and trans couplings are usually through bolted together with Nut and Lock Washer, a fine threaded grade 8 bolt.

I am wondering if prior own made it "easier" to install by tapping the trans coupling.
Nice and easy to install that way...but tough call as to whether it will stay tight.

Soon as bolts loosen enough for coulpings to move its game over...the bolts are meant to clamp the two coupling faces together creating high friction between the two and transmit power. Once loose its the shear strength of the bolts and thats not enough...especially loading and unloading in and out of gear.

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 14:31
by Joseph Fikentscher
Carl, only the trans coupling is threaded. The shaft coupling is not. There is only enough room for about 1/4 inch on the rear of the shaft coupling.

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 14:38
by Joseph Fikentscher

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 15:09
by Carl
Damn...so much for that thought. Looks like threads are right into a tapered portion of coupling on back portion of flange. A nut or bolt wouldn't seat well...or in short...looks like trans coupling was and is threaded as per plan.
Not something I am familiar with...I'd much rather have nuts and bolts to really tighten the two.

Moving on... spray it up, let sit, heat, tap a bit, spray.. try again.
Careful with EZ outs...nothing EZ about them.
If you can center hole better? Dremel - going up an EZ out size, as to not bust the EZ out in there.

Worst case, its a new trans coupling or Redrill and tap new set of holes...if those threads are a bit worn the bolts are not going to stay tight for very long.

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 15:43
by Joseph Fikentscher
I am assuming if I redrill and tap, the bolt size would be larger. Would that give me more strength?

Re: Shaft Coupling Bolts

Posted: Aug 19th, '19, 21:01
by Carl
If you redrill and tap existing holes, you need to go up at size.
Or you reposition then drill and tap to the same size.

Yes larger bolts will be stronger, but I don't think the issue is the strength of the bolts if your using grade 8 bolts. If grade 8 and shearing I am fairly sure they are loosening first. Once loose couplings are not clamped together, no friction and the rotation is shearing the bolts.

Re: Shaft Coupling Bolts

Posted: Aug 20th, '19, 08:56
by Rawleigh
Using the right locktite may help with the loosening issue, but they should back out with a left handed drill if so. While you have them out, have a machine shop face them. The look a little rusted and dirty. If the face isn't clean and flat they will not pull up tight and can loosen us. You want those flanges perfectly clean, flat and in line with the bore for max clamping. Carl can give you better advice on that though.

Re: Shaft Coupling Bolts

Posted: Aug 20th, '19, 09:21
by 1962 31
joe if you need any tools pullers drills easy outs give me a buzz at my shop 7328992060o im right in point pleasant

Re: Shaft Coupling Bolts

Posted: Aug 20th, '19, 15:30
by Joseph Fikentscher
Tom, Thanks but I just took it to a machine shop so they can get the bolts out.

Re: Shaft Coupling Bolts

Posted: Aug 20th, '19, 16:15
by Carl
As its off, do as Rawleigh said, have em true up the face...and make sure the thread are not sloppy...happens when loose bolts get knocked around. If threads are not in good shape...your choice of clocking bolt circle over for a new set up threads...or go up a size...fine threads to really cinch down and not back out and us grade 8's torqued to spec for that size.

Re: Shaft Coupling Bolts

Posted: Aug 21st, '19, 08:49
by Joseph Fikentscher
Thanks guys. Wont get it back till next week, so another weekend of no fishing. I'll update when I have progress.

Re: Shaft Coupling Bolts

Posted: Aug 21st, '19, 09:57
by Carl
Joseph Fikentscher wrote:Thanks guys. Wont get it back till next week, so another weekend of no fishing. I'll update when I have progress.
Come by me, we'll sit in the parking lot looking at the boat and tell fish stories...maybe go inside, look at the boat and tell fish stories over a cold one. Or maybe I should just work on mine.... nah. Cold one and fish stories.