Vibration at idle
#1
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This season I noticed a vibration at idle when in neutral. I was concerned that it was the gimbal bearing or a U joint. I just pulled the drive and everything looks fine . I checked the engine alignment and I can spin the alignment tool with two fingers. If I grease the alignment tool and insert it and look at the pattern that the splines of the engine coupler left on it, I would say it is maybe a millimeter off. Its almost even all around but it dose favor one side. Its that close that I don't want to mess with it.
Also I did a lot of work to the boat . It is very solid and I have solid motor mounts. maybe it is just normal and I am just noticing it now that everything on the boat is tight.
Any thoughts
Also I did a lot of work to the boat . It is very solid and I have solid motor mounts. maybe it is just normal and I am just noticing it now that everything on the boat is tight.
Any thoughts
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#2
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Make sure you recheck the alignment after turning the engine 180 degrees. I actually do mine in 4 places, every 90 degrees. Ive seen couplers out as much as .025.
#3
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if the coupler is out what dose that mean ????
I know what you are saying but is this a consern that requires a replacment of the coupler.
I know what you are saying but is this a consern that requires a replacment of the coupler.
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Well, the bad news is it requires removal of the engine. The coupler bolt holes can be drilled oversize and the coupler moved until its centered and then pined in place. I use a zero tolerence shaft that fits the primary bore of the coupler spline and a dial indicator to make sure its close before I put the flywheel housing on. They are usually pretty close but not always. I dont think they move any with time or wear, just made that way. Typical production parts. A different one might be right on.
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Now I'm wondering if I really screwed up?? I recently put new engines(502/bravo's) in my boat. The couplers and flywhells were in good shape so I reused them. The bolts that secure the couplers to the flywheels seemed like a snug fit so I didn't worry too much about the coupler not being aligned right....and I'm not sure that I got the port/starboard back on the respective flywheels.
Now the engines run great but I have a severe knocking from the port engine from the transom area. I was thinking it was just a ujoint going bad but now I'm wondering if my couplers might be slightly off center and causing the noise.
A lot harder to realign the coupler than replace a bad u joint.
How important is it to check the runout on the couplers? or do the stock bolts usually get you close enough??
Now the engines run great but I have a severe knocking from the port engine from the transom area. I was thinking it was just a ujoint going bad but now I'm wondering if my couplers might be slightly off center and causing the noise.
A lot harder to realign the coupler than replace a bad u joint.
How important is it to check the runout on the couplers? or do the stock bolts usually get you close enough??