Alignment/coupler

Hello all,

I watched Pete's video on alignment and have removed the bolts connecting the vdrive coupler to the shaft coupler. With all bolts removed, I can not get the two surfaces to come apart. Does anyone have a trick for this?

Ok, thanks. I will try that after dinner.

Well, I finally found a way to get consitent readings. I pulled the shaft aft and let the shaft stay? (ring around the shaft with allen bolt that keeps the shaft from sliding back in the event the coupler lets loose) rest on the packing nut. I spun the prop multiple times and came back with consistent numbers which weere close to my original numbers before I had everything loosened up.

Now comes the fun part of shifting the engine and vdrive just a bit.

It has been a frustrating day to say the least. I can not get this thing aligned to save my life. I have ran out of motor mount adjustment on the forward engine mount that I need to make the coupler get within limits at the coupler and have the strut straight in the log.

I can get it in limits but the strut ends up being offset from the coupler and it would put a bind on the shaft if I connected it.

I have looked behind the boat and the shaft is perfectly lined up with the rudder by the eye when it is not coupled and I can spin it with a finger.

Not sure where to go from here.

When the shaft is sitting in the log without being connected to the coupler, shouldn't it be straight as long as there is no bend in the shaft?

Could it be that my strut is about .004 off line causing my issues? I know the shaft is not beant due to it does not matter if I spin the shaft and measure the port and starboard sides I get the same readings as before which are .004 different from each other.

How can I check to see if the shaft is centered in the log?

It sounds like you are chasing the alignment around. As Bruce implied, you need to determine where the shaft spins freely in the strut, and then align the powertrain to that point. It helps if you physically support the shaft to stay in place, otherwise it will move around under its own weight. You definitely dont want to move the engine to where the shaft sits under its own weight.

Ideally, the strut and log will be aligned to each other (such that the shaft spins freely when its centered in the log), but that is not entirely required. So long as the shaft has sufficient clearance in the log (not rubbing or dangerously close) at the point where it spins freely in the strut, youre ok.

Just to make sure Im understanding you, here's my translation:

shaft log = shaft log hose
bronze hull tube = shaft log

If thats the case, nice trick... assuming theres room to pull the shaft log hose forward.

Agreed that to get this far, strut to log alignment must already be correct... otherwise you need to take a step back and start from the beginning!

Evidently I am in a little over my head. But, that is how I learn a lot of things. This may end up costing me some money, but I am going to figure this thing out.

Here is the reason I wanted to check alignment, I originally bought the boat grom the original owner with 289 hrs on it. He had a prop strike and had white lake marine straighten the shaft, put a new prop on it. The first time I owned the boat, it ran perfect. No vibrations, nothing ran great. I sold the boat to my buddy as I took a job in a coastal city and did not want my correct craft in salt water. We ended staying in Atlanta and about a yr later my buddy needed to pay college tuition for his kids and I bought the boat back. After I got it home I realized one of the prop blades was bent after I brought the boat up to about 32mph it had a small vibration. I sent the prop out and $150 later it is perfect again. While it was out, I decided I needed to address an oil leak in the vdrive and I would go ahead and align it.

The prop looked like it had hit something without the prop spinning. It was a minor bend, but I like everything to be perfect and I had a small vibration.

I plan on starting from scratch on this project and seeing if I can figure this out. I plan on removing the packing nut and trying to make sure the shaft is centered in the tube. I am not exactly sure how to start from scratch on this project. All motor mounts are loosened up so the motor moves freely with a crow bar. But, I need to make sure the shaft is centered in the hull. I am thinking I might just throw a new shaft at it to be extra sure that everything is straight. But, feel I might just be wasting money.

If there have been prop strikes, I would bet that the strut is bent and this is causing all your issues. If the shaft does not align properly in the shaft log (or reasonably close anyway as Tim stated above) your first order of business is removing the strut and verifying that it isn't bent.
John and I were chasing a shaft alignment issue in his boat and were experiencing the exact same problem that you have. We had the engine pried over until it was up against the front engine mount and the coupler alignment was still off. When we removed the rubber hose from the shaft log we found the shaft was actually rubbing against the shaft log. We ended up removing the strut and found it was indeed bent.
Keep in mind that looking at a bent strut with the naked eye you'll probably never see it unless it's pretty severe. Your only option is removing it, getting it straightened, reinstalling and then go through your alignment.

baitkiller wrote: the Professor will likely find error but in general terms: The shaft LOG is the packing gland assembly or seal carrier in drip less type. I lump the hose in with it. IE: Shaft log clamps means the hose clamps for the shaft log attaching hose. A hull tube is hull tube is a hull tube regardless of what its made of

I hate to nit pick, but your terminology is still incorrect. As Pete's diagram indicates, the shaft log, shaft log hose and packing gland are all separate pieces. If you wanted to lump them all together and refer to them as the "shaft log assembly" then I suppose that could be correct- but not exactly helpful in this scenario, since alignment does not deal with the shaft log hose or packing gland (only the strut and shaft log).

People have a hard enough time grasping the concept and procedure of aligning an inboard... mixing terminology up doesnt help things.

Eddie, Ive run into that same scenario you describe a few times- the strut being misaligned (bent or simply installed incorrectly) enough to cause the shaft to rub the shaft log. Yikes! It sure doesnt take much misalignment of the strut to cause a big problem at the log (which will multiply by the time you get up to the powertrain). Even a straight and properly placed strut can move around enough within the mounting bolt holes to cause issues.

Riley wrote: I can see how straightening from left to right can be done, but what about up and down if you don't know what the spec was originally? Of 4 old Correct Crafts I've pulled apart, 3 have been rubbing the bottom of the strut or within 1/millionth of an inch of it. I'm not sure if boats settle or they were just poorly lined up from the beginning.

Maybe I am missing what you are saying, but if it was really low I would shim the back of the strut.. or alternatively sand the front side of the mounting surface down a little down a little.

When checking a strut for straightness, I understand how you can tell from right to left, but the angle would be hard to determine if you didn't know the spec. One of our boats hit a BFR at idle and wrecked the prop and bent the shaft. The strut looked straight, but the shaft was darn close to the bottom of the log like about all the other boats I've seen. I didn't know if we caused that or if it was like that before hitting the rock. We removed the strut and had it and a spare checked for straightness. They were both straight and the angle on one was 16 degrees and the other 17 degrees. We put the original back on which was 17 and shimmed the back to get us in the ball park, but I had wondered if it had been bent and we had to bring it to a machine shop, how would they ever know what the angle it was supposed to be?

Before pulling the strut, Id pull the packing gland and shaft log hose and see how centered the shaft is in the log. If its pretty close to centered, then leave the strut alone. If its way off (rubbing the edge of the log) then its probably worth pulling and sending out to be straightened.

Bruce, Im guessing a shop will only check straightness side to side... CC didnt readily advertise specs on strut angles so far as I know, and I doubt a shop would go looking for it. A hit hard enough to change the angle significantly is likely to render the strut unfit for reuse anyways, I suspect.

TRBenj wrote: Bruce, Ive seen that as well (rubbing the bottom of the log). My guess is that the misalignment was there from the factory (as opposed to hull sag) but I dont know that for a fact. I dont think a shop can do anything about that, even if they were to have the strut spec in hand- the castings are fairly rough and will vary a bit from piece to piece. Fore/aft adjustments would need to be made at the time of install- washers under the base is the common trick... though massaging the angle of the base slightly can be done as well (we did this on the BFN). A grinder, a file, and a little bit of patience is all it took- a steady hand helps too!

I hear you on this one Tim. John's was rubbing pretty hard on one of the sides but up and down was pretty much dead on. It was straightened out nicely and when we tried to put it back in, we stuggled a bit trying to get that thing centered. By "WE" you should all know that it really means "I". You all are fully aware of keeping any tools out of John's hands?!?!?!?!?
Anyway, side to side was good then but the up and down was off. I ended up cutting apart a stainless feeler gauge and if I remember right, I ended up using a .020" or .021" blade stuck under the base of the strut to get the shaft centered. It's amazing how much that .020" at the base of the strut moved the shaft in the shaft log. Worked out great though.

Yes