Vibration when turning hard left or right at low speeds, help!

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gardenstatesurfer

Petty Officer 3rd Class
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Jun 6, 2005
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Hi all,<br /><br />I have a '90 Bayliner Capri with a v6 4.3L Mercruiser, I/O, Alpha I drive.<br /><br />I am experiencing vibrations at low speed turning.<br /><br />I looked at my prop and it does have a pencil eraser size ding in it on the end of one of the blades. Is that enough to experience this problem?<br /><br />Also, after researching old threads, I imagine I am suppose to look at the U-Joints? What the heck are those and where can I find them. <br /><br />Also-if you disagree with my diagnosis, please let me know what else to check. Please use simple terms as I am a newbie boat owner struggling to maintain it himself.<br /><br />Thanks everybody!<br /><br />Dave
 
L

Laddies

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12,218
Re: Vibration when turning hard left or right at low speeds, help!

Sounds like u-joints if you don't have a idea the first thing to do is buy a manual, the u-joints are in the bell hsg. the unit must be removed, shift it into forward gear to align the shift shafts, remove the cyls from there aft attaching point remove the 6 nuts and the unit will pull out. Before reinstalling it replace the gasket and quad ring
 
flashback

flashback

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Jun 28, 2002
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Re: Vibration when turning hard left or right at low speeds, help!

Hello GSS. yep that vibe could be the first indication of bad universal joints on the input shaft.... like Laddies said, if you are going to tackle replacement yourself, get a manual..it's not too difficult, but you do need a manual and a good mechanical ability...
 
Wotknot

Wotknot

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Re: Vibration when turning hard left or right at low speeds, help!

Also, after researching old threads, I imagine I am suppose to look at the U-Joints? What the heck are those and where can I find them.
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Dave, no disrespect, but........IF you don't even know what u-joints are or even where they're at, you might save yourself some grief, headaches, and more than likely even more money than what someone would charge, by letting a pro do it.<br /><br />Sure, we all like to take care of stuff ourselves when it comes to our "baby" but be realistic. I work on welding machines, plasma cutters, etc and I've had to fix more screw-ups by some people who didn't have a clue what they were doing. Resulting in more cost to them. As Dirty Harry said so eloquently, "A man's gotta know his limitations" <br /><br />However if you're bent and determined to tackle it, by all means get a manual and ask lots of questions here because there are some great people here with lots of knowlege willing to help.
 
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gardenstatesurfer

Petty Officer 3rd Class
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Jun 6, 2005
Messages
75
Re: Vibration when turning hard left or right at low speeds, help!

looking at my manual (clymer) its pretty vague...what do you guys think it would cost me to have it fixed (assuming it is the u-joints) at the marina?<br /><br />beleive me, i would rather do it myself, but im finding this one kind of itimidating looking at the manual.
 
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gardenstatesurfer

Petty Officer 3rd Class
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Jun 6, 2005
Messages
75
Re: Vibration when turning hard left or right at low speeds, help!

i guess we posted at the same time wotknot. i agree with your thinking. i barely was able to replace the damn starter at the beginning of the season. this one seems over my head.
 
Don S

Don S

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62,321
Re: Vibration when turning hard left or right at low speeds, help!

Get yourself a real manual from Mercruiser. Or, use the link below for the online manual for your outdrive. check section 3A for the ujoints.<br /> http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf <br /><br />The put that Clymers manual where it belongs.<br /><br />If you decide to get it done, and All that is done is to pull the drive and replace the ujoints and reinstall, you are looking at approximatly 1 to 1.5 hrs.<br />Plus the price of ujoints and drive install gasket kit.<br /><br />
outhouse.jpg
 
Liquid_force

Liquid_force

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May 7, 2003
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318
Re: Vibration when turning hard left or right at low speeds, help!

I apologize for the semi-hijack, but I have the exact same problem with my 4.3 OMC. Prop is in excellent condition (rebuilt before the season). I replaced u-joints and there was no improvement (btw - took me less than 2 hrs and I'm no mechanic).<br />Any reason to expect a new gimble bearing to improve the problem?
 
H

hoot

Chief Petty Officer
Joined
Sep 8, 2002
Messages
434
Re: Vibration when turning hard left or right at low speeds, help!

gss, i just did my own on a pre alpha. i had a vibraton in the outdrive and noise when turning. the merc shop quoted me approx 200 for parts and 400 labor. my unit is older and may be built a little different. i needed a special wrench to remove the drive shaft nut and a press to push the old u-joints out. and the nut is in there at 200 ft-lbs torque!! i used the website don s gave and a seloc manual. after i got the shaft out, the u-joints felt good, no loose play and they moved smoothly. but when i got the bearings off, there were ripples on the hardened ends of the crosses. the cost for merc parts was very close as i needed a seal also. i saved the labor cost and the experience was priceless.
 
X

xltier

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May 20, 2004
Messages
636
Re: Vibration when turning hard left or right at low speeds, help!

when my 5.0 merc vibrated on turns it was only the gimbal bearing growling.u could feel it thru the gunnels.it had got rain water inside the hull because i had left the plug in the boat.the water ran back around the shaft and ruined my new gimbal bearing.lesson learned.
 
G

gardenstatesurfer

Petty Officer 3rd Class
Joined
Jun 6, 2005
Messages
75
Re: Vibration when turning hard left or right at low speeds, help!

don, the boat got pretty swamped with water (water was coming up above carpet) last season. i beleive this is what corroded my starter. does that make you lean more torward checking the gimbal bearing?<br /><br />thanks,<br /><br />gss<br /><br />ps- the more special tools i need to buy the more i think this isnt worth trying to do myself. what you guys can help me with at this point is telling the marine mechanic where i would like him to start first given the history of the boat.
 
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