common and not so common questions

I saw what I believe to be a severe case of what can happen with mis-alignment. My nephew had commented last year that his stepdad's boat had to have a new prop shaft put in because the old one broke in half. I'm not sure where. Anyway they had a small inexperienced (in my opinion) shop replace it. About a month ago I get a call from my nephew asking if I could go get his stepdad who was stranded on a strangers vacant boatlift. To make a long story short, we found that the entire fiberglass area supporting the stuffing box was GONE! The shaft had apparently vibrated enough to finally fail and shatter this area, making about a 2" by 4" long hole in the boat bottom. The boat is (or should I say was) an early 90's Supra.

i can still turn unaligned boats by hand, they will turn, and it will also turn much easier once aligned, so the answer is no, I spoke with the doc last night about alignment because i aligned a customer's 2.50 shafts, those have to be perfect because there is very little give in a thicker shaft and in this case if out of align they are real tough to turn because the thicker shafts dont give like these 1" ski boat shafts, the problem with the thinner shafts is they have a tendency to whip, also the shorter the shaft the more critical the alignment. I also spoke with backfoot yesterday about his engine to hull clearance, he hand very little clearance between his oil pan and hull and he was concerned in which he should be. You can be in align and have this situation, what you need to look at is the strut bearing in this case the shaft may be pressing down the rubber in the front of the strut at the bottem and in the rear it will press at the top which means the shaft is not directly in the center of the strut, in this case he would have to move all 4 mounts up more so in the front to accomadate the angle then make sure the shaft is in the center and then proceed to re-align

Here is a link that should help answer your questions, so long as it works.

http://www.correctcraftfan.com/forum/forum_posts.asp?TID=6037&KW=alignment

the boat im on now has a Borg Warner in it, 1.91:1 ratio, Both transmissions were rebuilt in 2003 and aligned, the guy did hit something with the port prop and bent the shaft and while spinning the shaft i heard and felt alot of clatter, I proceded to tear the rear of the trans off noticing one of the mounts was backed completely out (inboard port)
The entire output section was shot due to the mis-alignment, luckily for the owner the surveyor recognizes it as damage from striking the object and is covering it,
thanks to the insurance company he is getting a rebuilt trans, shaft and fitted coupling, prop, rudder and rudder port, damper plate. the damage alone from the mis-alignment is in the 2k range and thats why i always preach...and practice alignment on these boats. I cant stress enough how important alignment is, 20% of transmissions fail due to mis-alignment and when they do its not hundreds in damage, its usually thousands because of the severity of the damage

shimstock, it is a common practice and alot of the old Chris's use them, going on a final alignment tommorow, man i dread it but it has to be done

backfoot100 wrote: M3Fan wrote: This makes it almost impossible for me to get a wrench around the rear mount adjustment/lock nut. Any ideas for a tight situation like this? Joel; I just ran into this exact scenario on my boat. I ended up using a flat punch and hammer on the corner of the nut to move it enough so I could adjust the height. Then just did the same thing to lock the nut down again. Didn't take too much effort at all and didn't scarf up the nut either. In fact, I first thought that I could use a crowsfoot wrench on it, but there aren't many places that you can find them anymore. Let alone one thats 15/16" so my search for something like that was short lived. The punch and hammer worked great.

Excellent idea. I'll try it out!

Eric,

Another great reason for you to make the trip to GL next summer, you could do an "Alignment Clinic" which could be documented for the site, bring the whole family and write the trip off as a business expense, bonus is Hollywood will have his typical full cooler of Wine Coolers for you to indulge yourself with.

Eric,

Also, on my current boat the engine is pushed over to the starboard side on the forward and rear mounts. I figure the factory probably slides the engine one way or the other as a fudge factor from one hand-made boat to the next. This makes it almost impossible for me to get a wrench around the rear mount adjustment/lock nut. Any ideas for a tight situation like this?

most maintanance manuals say once a year or after you trailer the boat, i would make it routine and include it in winterizing or spring start-up, it is the cheapest tune up you could ever do on the boat, you would be surprised if your out of align and re-align it how much better the boat will perform, remember: a boat out of alignment means more load which means more horsepower to turn the prop, I hate doing alignments more than anything but it is something that can't be overlooked, you remember a few months back when i contacted you about that pro-star, well that ended being out about .021 and it was causing the output bearings to heat up and foam the oil, at that point it would come out the breather and into the bildge, that had 3 trannies in it and finally i made him bring it down from Chicago and personally aligned it for him. once he left i never heard from him again, problem solved.

once again i cant strive how important alignment is and how costly it can become if a boat is out of alignment, I will probably retire early due to mis-aligned boats, i have 2 this week, without getting into the business end, one left yesterday at $1731.00 because of mis-alignment. in a way i feel like the chef giving away his secret recipe which is taboo, but there is plenty of tranny work out there. the other one is due to leave Friday and im too embarrassed to say how much. these are larger boats, but the same rules apply for all inboards.
I ask alot of questions to customers usually and most.... 95% do not even know you have to align a boat and I think a little more than a year ago alot on the site may not known much about alignment. In my eyes a misaligned boat is like running 3 quarts low on oil...would you let that happen? probably not
Maybe we could add the alignment topic to this topic