Bravo 1 vibration in forward drive but not reverse?
#1
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From: Tampa, FL
Noticed a vibration in the outdrive when shifting into forward..... reverse seems to be fine? This was noticed only at idle putting my boat on the lift but it was enough for me to feel that something may be wrong? I did not notice anything while driving the boat but lets just say there were a lot of "distractions'!
Here is where I went wrong, I had 8 people and 2 dogs on board and it took about 3/4 throttle or more to get the boat to plane. Tabs full down and drive all the way in and it took a while for the 26ZX to plane. I only cruised at 3,000rpm in a 2-3 ft chop but I think I may have put a little too much stress on the Bravo 1? Motor is a newly built 509 making around 575-600ft/lbs of torque...... I have no experience with drives or props and I am using a 26P that was recently cleaned/welded, and buffed and it has performed perfectly so far...... Does this sound like the hub may be on the way out?
Here is where I went wrong, I had 8 people and 2 dogs on board and it took about 3/4 throttle or more to get the boat to plane. Tabs full down and drive all the way in and it took a while for the 26ZX to plane. I only cruised at 3,000rpm in a 2-3 ft chop but I think I may have put a little too much stress on the Bravo 1? Motor is a newly built 509 making around 575-600ft/lbs of torque...... I have no experience with drives or props and I am using a 26P that was recently cleaned/welded, and buffed and it has performed perfectly so far...... Does this sound like the hub may be on the way out?
#4
You could likely have a chipped gear tooth. Depending on where it is in the drive, that chip on the tooth would only be loaded in forward gear, not reverse.
Have someone start the boat, put it in gear, and idle forward and backward.
VERY CAREFULLY, and make sure the captain's eyes are on you. Lean over the back of the boat, and put your hand on the top of the drive.
If you feel the vibration through the top of the drive, it's a chipped tooth.
Have someone start the boat, put it in gear, and idle forward and backward.
VERY CAREFULLY, and make sure the captain's eyes are on you. Lean over the back of the boat, and put your hand on the top of the drive.
If you feel the vibration through the top of the drive, it's a chipped tooth.
#5
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From: Tampa, FL
OK thanks...I do have a trailer for it and I was thinking about pulling it out of the water and checking it out.... I do have about a 10 minute idle to the boat launch so I hope it will be OK for that..... the vibration was not what I would consider moderate or severe at all but it definitely is not normal and I would not consider putting any kind of power to it...... I think I will put it on the trailer and report back...... thanks......
#6
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From: Ft. Worth TX
Also use a real doctors stethoscope all over the outdrive with the boat on the trailer while running it. They really can isolate problem areas much better than a mechanics stethoscope and your own ears. Also watch the balance & straightness of the prop and propshaft from behind as someone shifts in and out of gear - fwd & rev.
We use a real Docs Stethoscope all the time and it works great for picking up and isolating noises & problems especially bad bearing in belt pulleys along with valve train noises. Anyways just an FYI on top of.
You will be surprised how well a quality docs stethoscope will help you find problems and find them in the correct areas. A good one can be bought for about 100 bucks currently.
IMO I think also you could have a problem with the fwd gear.
We use a real Docs Stethoscope all the time and it works great for picking up and isolating noises & problems especially bad bearing in belt pulleys along with valve train noises. Anyways just an FYI on top of.
You will be surprised how well a quality docs stethoscope will help you find problems and find them in the correct areas. A good one can be bought for about 100 bucks currently.
IMO I think also you could have a problem with the fwd gear.
Last edited by BUP; 08-14-2014 at 02:48 PM.
#7
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From: Tampa, FL
OK, just ran the boat on the lift with the hose and the prop does not vibrate or shake the boat at all like it did in the water......... put my hand on the upper plate on the drive and it felt very solid with no vibration or noise........ but.... looking at the prop while it was spinning and it did not look like it was spinning true? The back of the prop appears to be moving out of round but the front part next to the drive looks normal so I would say the hub is toast?? The standard rubber one is good for 400HP from what I have read so should I get the solid hub? I kind of like the idea of having the protection of the rubber to cushion shock loads? I never had a problem until I planed the boat with too many people......I don't jump the boat and I am always easy accelerating so would I be OK with the low performance hub or get the solid??? Thanks.... TBF
#10
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From: Tampa Bay Area Florida/ North Miami Florida
Hey flyer.. Chris here from Dunedin. That style hub is probably ok for you.. 8 people on a boat is not ok unless its 30 foot plus tour operated boat. Anyways . First and foremost, Make sure you have towboat us or seatow membership. Next wait for a calm day and take the boat out for a short hop. If it vibrates bad again, call seatow and get towed in. DO NOT MENTION IT DID THIS BEFORE TO THE TOW BOAT PEOPLE.. Don't ask.. My guess is it had seaweed or a plastic bag or something on the prop and now it has cleared.. The hub alone would not get better on its own ..If you take the prop off and it is intact then it is fine. As for the wobble, A bent prop shaft can do that.. Did you hit anything. Sometimes that outer ring on the prop is not as true as the rest of the prop.. To remove the prop, go buy a 1 1/16 inch DEEP WELL Socket.. Dont waste your money on the monkey prop wrench at west marine.
Chris
Chris





