View Full Version : Driveshaft alignment? Moving strut? Shimming motors?
thefishingfreak 05-03-2011, 08:22 PM I've also asked this on noreast.
The New Cutlass bearings are pressed in and shafts are cleaned up and installed.
One shaft slides perfectly up thru the strut and into the stuffing box as strait as a laser.
The other one is a good 1/8"- 3/16" off from lining up and takes so much force to get it thru the packing box it basicly gets jammed. It was like this all last season.
Should I remove the strut and clean up the 5200? See if there's enough play there to align it with a simple re-positioning of the strut? Re-5200 it down and lock it up?
Second question, how critical is motor to shaft alignment?
I've heard of feeler gaugeing the Shaft coupler to the tranny for precision alignment.
On One motor I will have enough adjustment in the mounts to get it dead on. . The other I will have to shim the motor mounts on the stringers as it's at least 3/16" off from the stuffing box and the shaft center to the tranny. That is also the strut in question.
Third question
Should all these adjustments/ motor mount shimming be made in the water? I know the boat flexes somewhat
Rip Runner 05-03-2011, 09:30 PM Mike,
Were you getting vibration out of that side last year? Sounds like you probably were. I just installed new shafts during my re-power and will be talking to my marina tomorrow. I'll see what they have to say as their opinion will be much more educated than the one I was about to give.
MakoMike 05-04-2011, 11:41 AM Mike, Listen to the advice you got from Paul on Noreast, the guy really knows his stuff.
Mr. Sandman 05-04-2011, 12:31 PM I have never done it but have seen it done in a boatyard. They used a laser to set it up. You want the shaft alignment as perfect as possible I know that much. If you have to force it that much it is too far out and you will feel an RPM based vibration and excess wear on the cutlass.
I read the nor-east post, it sounds like he has been down this road more than once.
Best of luck with this job.
beamie 05-04-2011, 04:59 PM Mike,
Haven't read the Nor East post but part of my job is aligning pumps to motors and such.
Boy last year must have been a bit rough if off by 3/16"
This is critical.
You would want the shaft coupling to gearbox coupling within 2-3 thousanths, angular and axial. In reality on small boats you can only do this with a straight edge and feeler gauge so it never is as accurate as a rim and face dial or double dial or laser alignment so if you can get it less than 5 thou your doing good.
Final alignment you want to do in the water. All boats flex, not just old wooden boats.
Now you say this bad engine the shaft is tight now. Uncoupled to the motor the shaft will not turn easily? How many struts do you have? If the shaft is tight just going thru one and/or 2 struts and the stuffing box than that issue has to be dealt with first. This will just wear your new cutlass out fast. So yes you may have to remove the strut and shim it to the hull and let it find its home as to not bind.
When that is done. Alinging motors to shafts if they are out allot you may run out of adjustment on the mounts, may have to relocate mounts and shift the engine. You want to deal with the angular alignment first and then do the axial. On nice mounts on bigger engines you have jack screws which make things easy. You probably have this on your mounts for angular adjustments, many times and industrial situations angle iron and bolts are welded to do this task for the axial alignment. In your situation a wooden block and 10 pound hammer and crow bar for shifting the engine may have to do. Again, reality in small boats to roomy plant installations.
If I were home I'd take a look at it for you but am not now. Good Luck.
thefishingfreak 05-04-2011, 06:08 PM A pic tells the story.
Here's the good motor. The starboard side.
http://i6.photobucket.com/albums/y250/thefishingfreak/788d7d6f.jpg
The strut to stuffing box alignment seems dead nuts on. The engine/gearbox to shaft coupler is a slight but off and shoul be able to adjust using the mounts. The motors are mounted on the large, rubber mounted, single stud type adjustable mounts.
Here's the port shaft coupler. This Is after the shaft has been forced up thru the stuffing box.
http://i6.photobucket.com/albums/y250/thefishingfreak/5ed6e6e5.jpg
there is not enough adjustment to fix this.
Plus this is pretty much where the shaft wants to sit with the strut the way it is now.
http://i6.photobucket.com/albums/y250/thefishingfreak/86972024.jpg
http://i6.photobucket.com/albums/y250/thefishingfreak/21582e5b.jpg
it's a single strut set up. This was the way it was when I hauled out. The stuffing box was just about blown out.
http://i6.photobucket.com/albums/y250/thefishingfreak/51eba91e.jpg
Posted from my iPhone/Mobile device
nightfighter 05-04-2011, 08:00 PM That's ugly. Strut is definitely out, judging from pics. Make sure it has same dimensions of good one. As mentioned, start with strut. See what that gets you. Check to see if motor mount adjustments are maxxed on any plane. The laser mounted to the tranny face plate is the way to go, if you can find a mechanic with one. It will quickly tell you whether the motor is in line with stuffing box, which would make it less work.
beamie 05-05-2011, 12:04 AM Yeah, real ugly. Looks like the previous owner "adjusted" that one day.
So.......that strut got bent back at some point, think less angle. Without going the expensive route and replacing the strut the aft end of strut needs shimming to get the shaft up at forward end. Once you get the strut off and cleaned up, hoping the nuts are accessible..., you can couple up the shaft to engine keeping the shaft somewhat centered in the hole at the shaft log. This will give you an idea of how much the strut needs to be shimmed. At this point feel is the way to go....the easier the shaft moves the better the cutlass is lined up. It isn't the space shuttle so there is a little error built in for the rubber cutlass.
Once you have this done then go to the engine for final alignment. When you do this you have the common condition of rusty couplings in the bilge, they look good compared to mine, but this makes it near impossible to get a balls on alignment since some areas are more rusted than others, no matter if your using pricision instruments or feeler/straight edge. You just have to do the best you can.
I think anyones mother can get the alignment better than it is now so even if you don't get it perfect and you should feel the difference once in the water.
InTheHole 05-05-2011, 08:06 AM FF, maybe you already checked, but any possibility the shaft could be bent?
thefishingfreak 05-05-2011, 10:04 AM Shafts are strait I rolled them like you would a pool cue on the spraybooth floor.
Not exactly digital caliper laser measurement but if I was shooting pool, Id pick it for a cue.
Plus eyeballing it down the lenght look pretty friggin good to me there about 8 feet long so it's easy to tell if there strait.
Posted from my iPhone/Mobile device
thefishingfreak 05-05-2011, 10:10 AM Also I just went and spun the shaft with it sitting like this
http://i6.photobucket.com/albums/y250/thefishingfreak/86972024.jpg
and she don't wobble from this orientation at all
strut definitly out of alignment/bent
Posted from my iPhone/Mobile device
InTheHole 05-05-2011, 11:37 AM gotcha, just checking, I am usually guilty of not checking the obvious stuff first. I agree the strut is probably bent.
MrHunters 05-05-2011, 12:37 PM i'd get a new boat... is that helpful? :)
Mr. Sandman 05-05-2011, 01:36 PM As my buddy says..."This is one of those unfix-able problems."
fish4striper 05-05-2011, 02:31 PM As my buddy says..."This is one of those unfix-able problems."
anything is fixable- just time and/or money!
gl Mike, looks like you're on the right track now
likwid 05-05-2011, 04:40 PM Re-align the strut.
Be prepared to redo the stuffing box, I'm sure thats got a good drip going on.
I'm gonna assume thats the shaft that's worn?
Might as well invest in a new shaft while you're at it to start from nice fresh stainless.
Rip Runner 05-05-2011, 07:13 PM If you have to get new shafts make sure they are scalloped on the ends. It's not a brand new technology, but newer so the shop needs to have the computers to do it. If you need new one's let me know and I can get you in touch with the right shop.
thefishingfreak 05-07-2011, 05:48 PM Got the motor shimmed up with 1/4" plates up front and 1/8" plates in the rear. I lined up the motor with the shaft bolted up to it an blocked at the rear. Got it very close to perfect thru the packing box.
Then disconnected the shaft and worked on lining up the strut.
Filled and re-drilled holes as advised.
http://i6.photobucket.com/albums/y250/thefishingfreak/ead32512.jpg
http://i6.photobucket.com/albums/y250/thefishingfreak/2448d2b8.jpg
new placement of strut
http://i6.photobucket.com/albums/y250/thefishingfreak/9b88cd83.jpg
shimmed in place here. I put the packing box pack with the old stuffing inside for A closer line up. The shaft just about falls out, so I know it's perfect here.
http://i6.photobucket.com/albums/y250/thefishingfreak/086fe87a.jpg
new holes drilled.
http://i6.photobucket.com/albums/y250/thefishingfreak/2dc96c71.jpg
mixed up a batch of west system with thickener and chopped glass.
I put heavy mil Saran wrap over the strut and loaded it up with the resin.
I didn't crank the bolts down just snugged them up. All the while spinning the shaft.
I know it's perfect because the shaft will slide backwards and fall out if I'm not carefull.
Should be able to remove the bolts tomorow, clean up the trimmings abit and be back in buisness. The motors will need minimal adjustments once in the water to line up the couplers.
http://i6.photobucket.com/albums/y250/thefishingfreak/22189f44.jpg
Posted from my iPhone/Mobile device
Raider Ronnie 05-07-2011, 06:46 PM Could you imaging trying to get this done at the boat yard !
Guess it was a good idea cutting the tower to get it home.
nightfighter 05-07-2011, 06:53 PM Sweet!
thefishingfreak 05-07-2011, 07:03 PM It is nice to have it next to the shop. Too bad it don't fit inside :hee:
Posted from my iPhone/Mobile device
thefishingfreak 05-08-2011, 01:57 PM Popped the strut off this morning.
Came out as expected. In hindsight I should have shimmed it so the washers were not left in the mold. I picked the washers out none the less and it's where it needs to be.
http://i6.photobucket.com/albums/y250/thefishingfreak/6dcf182d.jpg
epoxy primed here.
http://i6.photobucket.com/albums/y250/thefishingfreak/9792de1d.jpg
reset it all in 5200.
http://i6.photobucket.com/albums/y250/thefishingfreak/d3526447.jpg
the finished line up. Much better.
http://i6.photobucket.com/albums/y250/thefishingfreak/2a05e03b.jpg
Posted from my iPhone/Mobile device
likwid 05-08-2011, 07:10 PM Did you replace the strut cutlass?
thefishingfreak 05-08-2011, 07:14 PM Did you replace the strut cutlass?
Yes, that's what started all this.
Posted from my iPhone/Mobile device
vBulletin® v3.8.7, Copyright ©2000-2025, vBulletin Solutions, Inc.
|