Maintanence Question on Juki 1508 NH

[MarineBozo]

Hey all,

I recently purchased a Juki 1508 NH (my first industrial machine!) and have been making some minor repairs and upgrades over the last couple of weeks before I put this workhorse to work.  There is really only one last issue I am dealing with.  That is whenever I use the knee lift, there is a low pitch squeak that comes from somewhere in the head unit (I'm thinking it's maybe the triangular link in front or possibly from the bushing/rod/spring on the presser foot rod, though not positive).  If I use the back lift there is no sound (it's very smooth) and if I leave the back lift up and engage the knee lift there is no sound (ruling out the arm itself).  It's only when it has the additional tension of being completely engaged using the knee lift that it makes the sound.  I also noticed that if I put a little lateral pressure on the knee lift when engaging it the squeak is louder making me think something may be slightly out of alignment.

I know it maybe impossible to know exactly what the issue maybe just from a description, but I'm basically looking for advice on first steps to diagnose where exactly it's coming from.  Should I just break down the entire head assembly while testing each time I take off a component. Then clean with alcohol, relube, and reassemble?  How would y'all go about it?

Another related question is that the previous owner seemed to put a thick grease around the springs of the presser foot rod.  I've never really seen grease used for these areas and thought this might be a no no.  Should I remove that? (You can see it in the photo)

Thanks!

 

 

[friquant]

On my pfaff 545 the knee lift was very hard to engage until I greased the area on the back of the machine where the plate slides against the body (and pushes on the rod to release the tension). I had already oiled everything, or so I thought. But when I finally removed that little piece and greased behind it, the knee lift became easy to use. Perhaps it is that there are parts underneath that oil doesn't get to easily. Or maybe the grease is just better at lubricating things that move  slowly like a knee lift. Anyway, that's the first place I would look. To go along with that, I would remove the thread tension assembly from the front of the machine, pull out the actuating rod that goes from the back to the front of the machine, and make sure the back end of that is greased.

Edited 10 hours ago by friquant