BLI F3 and F7

[peteski]

By putting the front truck in the rear position you are turning it backwards. The gear binding only happened when it ran forward. I have not run the loco backwards pulling a train (it only bound when it had a load on it) but in switching operations with only a few cars it has not bound.

Interesting . . . thanks.
So, it is not a real fix but merely a workaround. But if it is good enough for you, then that's all that counts. 

[Espeeman]

It does all I need it to do

[drbnc]

I wanted to update my findings with the jack-hammer front truck (F7A) in case someone else is having the same issue. I looked into all the suggestions offered and what finally worked was a simple solution someone here had mentioned. I switched the front and rear truck. The noise was coming from the binding of the gears in the front truck. Once I swapped them out, the noise stopped. Now it runs perfectly.

Guess this horse isn't dead.  After further issues with one of my sets, "jackhammering" was caused by loss of mesh on the lower idler gear (grabbed off the track as soon as it hit).  Eyeglass repair kit from the big "A" has washers which will work IF you are patient when you try to shim that lower idler.  It's a pain and WILL try your patience, but does work.  My other set jackhammered when the cover over the worm was loose (apparently), but is on the bench for it's washers.

Not sure how long swapping trucks will last, since they all have the same issue.  Between the short-shouldered idler gears and wandering idler axles, well...

[Maletrain]

Has anybody tried to make some sort of "fix", perhaps some sort of clip, that will keep the idler axles centered in the trucks?

[mighalpern]

Just wanted to touch base and see if anyone is still having issues or has found a solution
I have 3 sets and one set stuttered so bad that I sent it back.  It stayed there about a month and I got it back the other day.
I ran it for 10 minutes and it worked great, then the stuttering came back.  I cleaned the track even more, and ran one of the other sets and it  went slow and crawled very smoothly, no issues, even rolled my kato units thru, but not the repaired one, it cant get going.  I am truly bummed and would like to throw it away( or GOD send it back again  ), but there should be a better way.  I have some older Kato F units that need a few thousands removed from the frame and I can put the BLI shell on them, (I want the NP loewy scheme)  but then there is no DCC or sound. 

 However used shim/washers, can you tell me where you got them

Happy Holidays Guys
Miguel