vibration when put in gear - normal

[rocklobster]

Is it normal to have a vibration when placing the D4-260 in gear. I have never owned a diesel and assumed this was normal. Once the props turns a little, the vibration goes away. It is only when it engages for about a second or so.

Also, when I look at the stuffing box when starting up, the the stuffing box and the "hose" that it's connected to shakes around. I'm assuming this is because the diesel normally vibrates/shakes. That's why the stuffing boat is attached the to rubber main hose that connects it to the boat. The rubber, allows the system to vibrate if needed since it is flexible.

During all other RPMs and Speeds, it sounds great and has no vibration. Only that quick time when engages at idle.

Since I'm new to diesels, I thought I'd get your opinion.

 

[Navigator's Son]

Yes. A level of vibration is normal.

For me, if I'm running at low rpm, about 700 to 1000, my helm starboard window rattles. Once I get out of the no wake zone and can Rev a bit higher the rattle goes away. But I'm pretty sure the engine continues to vibrate all the time

 

[Red Raven]

May be normal but maybe not. I would check your engine mounts to make sure they are all tight.

 

[Red Raven]

May be normal but maybe not. I would check your engine mounts to make sure they are all tight.

 

[Cutwater28GG]

is there a torque rating for these or just "tight with a big wrench" tight?

 

[Red Raven]

You’d have to asked the factory about the torque rating. I don’t know. What I do know is a couple of mine were loose (finger loose!) when I checked them this off season. I tightened them as tight (tight with a big wrench!) as I could and rechecked the shaft alignment (which was fine). We did not have any vibration as two were still tight but I could imagine it causing your symptoms if they were loose. Unlikely, I suppose, but something I would check anyway.

 

[YukonRon]

Once you get the engine mounts torqued correctly, some people put "witness marks" on to watch if the nuts loosen off. Use a paint pen or brush to put a line of visible paint (white or yellow) across the nut and mount. You can keep an eye on it to watch if it backs off over time.

 

[Cutwater28GG]

thanks Curt, How did you recheck shaft alignment?

 

[Red Raven]

thanks Curt, How did you recheck shaft alignment?

Loosen the bolts holding the shaft to the transmission, back it off a bit and use a feeler gauge. The faces should be within .004” from each other (angular alignment), as well as the centerline (Bore or Parallel alignment, measured relative to the flanges).