Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Major engine vibration
Posted by glfarnes on 09/10/12 - 11:25 PM
#1
My starboard engine which is a 115 hp 1996 Johnson Ocean runner is vibrating badly. When the engine is in gear and revs to more than 2800 rpm it begins to shake the whole boat. I replaced the plugs and there was no change. Anyone know what this would be?
Posted by Michael A on 09/11/12 - 4:44 AM
#2
Badly damaged prop or broken engine mounts
Posted by contender250 on 09/11/12 - 4:52 AM
#3
10/4 on what Mike has stated
Posted by tom blinstrub on 09/11/12 - 7:23 AM
#4
Spin the propeller to see if the shaft is bent. The previous owner could have hit a rock and replaced the prop before you bought the boat. My friend whacked a rock and bent his. Also wiggle shaft to see if there is play.
Posted by Tom W Clark on 09/11/12 - 7:41 AM
#5
Probably needs a new power pack.
Posted by glfarnes on 09/11/12 - 8:47 AM
#6
The engine is also overheating. I should have mentioned that. I don't have any prop damage so I'll take the Livingston across the bay and pick up a couple power packs today and let you know if that was it Tom.
Posted by glfarnes on 09/30/12 - 10:16 PM
#7
I finally received new power packs and wires in the mail today and installed them. The engine refused to start and the best I could get would be a one second to three second sputter that blew great gobs of nasty oil and gas onto the water. I replaced the spark plugs which were soaked with gas and it fired up and ran up to full speed. There was no sputter or vibration at 2800 RPM and the boat came up on step for about a minute and ran at 5000rpm with no problems, but then the engine dropped off and almost quit, then came back up to 5000 rpm then quit altogether. I looked at the optical ignition and found the advance system stiff and sticking about half an inch from bottoming at Idle. I thought I had found a problem but found the other engine that runs great doing the same thing. Tomorrow I'll test both engines again but I'm not expecting any improvement. I'm stumped again.
Posted by dbcollen on 10/01/12 - 10:07 AM
#8
sounds like a fuel delivery problem to me, is the primer bulb sucked flat when it loses power? Can you pump the primer bulb and keep the engine running?
Posted by glfarnes on 10/01/12 - 3:25 PM
#9
I took it out for a spin this morning after a quick check of the fuel hose on the offending engine side. I did find that the hose was partly pinched and corrected that. When I brought the engines up to five thousand RPM all was well. I dropped back to a cruse at four thousand and ran for about a minute at which time the offending engine began to vibrate. I brought the engines down to twenty eight hundred and the vibration went away. I am right back to where I started other than when I dropped back to an idle the bad engine was idling at around twelve hundred. This may have been caused by cleaning the optical system in that the idle may have been raised to compensate for improper timing at idle. The boat is being pulled and put into storage tomorrow so I may have to have the big money guys look at if if someone here can't put their finger on the problem soon. Thanks for the suggestions so far. Put your thinking caps on because this is a dilly.