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Loanshark.
07 Merc 250 pro XS; We were running at 70 MPH in 20 feet of water and the lower unit comes off. Three of the 4 bolt studs were shered off clean like you cut them with a hack saw. The right front bolt was bent forward towards the bow. We didnt hit anything. I have hit submerged objects before so I know the difference. It looks like that maybe one bolt failed and then from that point on the rest started giving away from the excess force. Has anyone ever heard of a lower unit just breaking off before? I would sugest that when you undo your straps prior to launching the boat to look at the bolts on the lower unit and from time to time maybe even put a wrench on them to make sure they are kept tight. It doesent take long for a loose bolt to break off clean. Thanks
IT HAPPENED TO LES MILES LAST YEAR 6 TIMES…..YEP HE LOST HIS ASS….
We put a wrench on it and tightened the nuts!!BAYOU BANDIT
Call your insurance company, now that Robin and Sam have gotten in their football analogies, and the LSU – Bama jousting goes on, lets answer your question. We are not aware of any gearcase issues with engines of any brand loosing gearcases while in operation. Over the years we have seen these cases attempted to have been stolen and the culprits run off before the job could be completed, leaving the owner with a hanging case or worse, loosing the case in operation. The nuts are nylon locking nuts and we have never seen an entire set back off. We actually have never seen one back off, though have heard of this and are suspect to the theft analogy. We have seen more than one would suspect totally stolen. They drop the case and have propeller, gearcase and all for the hocking or replacing on a rig they have broken down. This also happens on aluminum wheels commonly as one person will loosen the wheel while the rig is parked, awaiting another to lift the trailer or jack up the rig. The culprits get run off by a boat launching or homeowner, and the result is a loose wheel or a set of them in transit. Hopefully no one gets hurt in either of these situations, though it happens.
Not to take away from the seriousness of the motor problem but Tideman, you might want to check your stats…. it was only 5 last year and only one hurt but we will take care of that on nov 7th in your back yard. Back to the issue, had a buddy have the lower unit “fall” off. the ins co tested the bolts and found they were not strong enough, seems they were not factory bolts that were apparently changed when he had lower unit serviced. big mess. good luck
What “bolts”? You mean “studs” for the main supports. No way they are going to shear off if they are tight, without a serious impact. There is not _that_ much stress on them and it is spread out over a large area. If you loosen them, then the moment of stress is increased and they can definitely shear, but I dont believe it will happen if they are tight. I go with BCBs analysis here. If someone tries to drop the L/U and gets interrupted, it will turn into a problem later on, as will an interrupted wheel theft. For reference, a Ford 8.8 ring gear is held on the carrier by 8 bolts that are about the same size as the studs on the L/U. They survive launches at the drag strip with slicks. And they dont shear. An outboard cant even approach that kind of shear load (launching at 6KRPM, dropping the clutch with 10″ slicks on the rear, rear axle “locked” so that both wheels spin together). Ive seen way too much mischief over the years. Windows broken out. Hitches damaged. Wheels damaged. I had someone lose a tire on the interstate, pull off into the University parking lot where I park, remove one of my wheels and with a gorilla accomplice, used a 4×4 to raise the rear of my vehicle to get the wheel off. They left me a torn up matching aluminum wheel with no rubber on it. With a prop going for over 500 bucks and a rebuilt L/U going for 2500 up, they are prime candidates for theft since you can remove one in less than 5 minutes. Some Rudes are harder since the shift shaft has to be un-done, making this a more obvious job in a parking lot. But still…2008 Pantera Classic2014 Mercury Pro XS 200
I 2nd oldtimer. Stainless steel nylon locking nuts on studs. It aint gonna fall off.
And only an idiot would remove the studs after removing the lower unit, unless something else needed to be done such as replacing the mid-section or something. If you have to park your boat where it is accessible, you ought to tie an alligator or something to the motor to keep the criminally-minded at bay. For example, here in Birmingham, parking at the BeesWax ramp is pretty safe. A fair amount of activity there. But go up to the Kelly Creek ramp and you may be the only vehicle there. A little trick to launch a big boat as turbines going on and off cause the creek to reverse-flow, etc. But even worse, the seclusion is a bit much. Brother had someone knock his van windows out to steal about two bucks in change, plus a couple of CDs. Had a friend lose two wheels at the same place. Ive heard of several prop thefts all over as well, as thats a 30 second rip and run job. Hopefully a boat manufacturer will offer a 2400v security system such that when someone tries to steal your property, you have a corpus delecti waiting for you when you return. 2008 Pantera Classic2014 Mercury Pro XS 200
Might increase the liability insurance a bit, though we would love to oblige otherwise. BCB
ot, the boly issue was more about the ins co not wanting to pay the claim which they havent as of yet and is a big mess. we never thought about someone trying to remove it but makes sense since the recent theft issues around the bend. good luck papa on getting it taken care of. brad
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