Older Kato F7A trucks

[ATSF_Ron]

Hi Guys,

I scored a cherry SP freight F7A on the cheap.  I need to remove the shell for lube/inspection but don't recall if the older trucks swivel off or not.  If memory serves, the newer ones can simply twist gently off, correct?  Or maybe that's the Fox Valley locos. Hmm...I'm hesitant to try twisting and break something.  I can't get the Micro Trains front coupler box off because of its size and position in relation to the front truck, even with the coupler screw removed, so I'm hoping a simple twist and release will work for the front truck.  The loco in question is Kato #176-215 if that helps.  I wasn't able to find any info online.  Thanks.

[ATSF_Ron]

Ok nevermind.  I just got it.  It's been a loooooong time since I've taken a shell off of one of these! 

[woodchip]

With the shell off loosen the screws holding the frame halves together then the trucks should drop out. Replacement trucks are not available anywhere and likely never will be.
                     Hugh in Canada



  "The road to hell is paved with good intentions"

[ATSF_Ron]

New issue.  Test run in forward was perfect.  Reverse?  Not so much.  Squeaking and squawking, herky jerky operation.  Took it apart down to the motor and nothing looks out of order except for being bone dry with no lube.  Lubed gears and bearings and reassembled.  Still quite noisy in reverse but improved at least 50%.  While apart I rotated the motor shaft with my finger and everything looks and feels fine.  Pushed the trucks back and forth and those are fine.  I'm riding the fence on this one.  It was a great price, but I may return it.  But the older Katos are such great runners and pullers...but with parts availability in question with these older ones, I dunno.  Further thoughts?

[wcfn100]

All the squealing in my older Kato Fs is from the motor bearings.  You need a fine tip to get between the motor and the flywheel.


Jason

[peteski]

Ron, when you look at http://spookshow.net/loco/katof.html , which trucks does it have?  The ones with metal gear case, or the low-friction ones with plastic gear case?

[ATSF_Ron]

Peteski, the trucks are exactly like the trucks in Mark's 2nd photo of his review.  It even has the same number stamped on it.  So that would be the low friction type with plastic gear case.  And I've decided to keep it, regardless of the outcome of this repair.  Finding parts for these older Kato units is a challenge, I hear.  I have 4 others of the same vintage, so I'll save this one for parts if need be.

wcfn100, I have a fine tip applicator and lubed anything that moved, lol!

At anything below about 20 scale mph (reverse only) the jittery speed is pretty bad.  Above that and it's mostly gone but still there randomly.  I'd describe the noise as a cross between a mini blender and an electric razor that's dying.  Very odd.  It's almost like a different locomotive in reverse.  In forward the noise goes away completely and it's buttery smooth.  Like all other Katos.

[ns737]

it could be the worm. I had one that the worm was making the noise

[peteski]

The sound seems to point to a problem with the worm meshing with the worm gear in the truck.  That usually produces that strange grinding sound.  I don't have that particular version of the loco, so I can't offer any specific advice.  Usually this mesh problem is caused by the either the worm bearings being too loose in their mounts, allowing to worm to move up, barely engaging the worm gear's teeth, or the truck not sitting high enough in the frame, causing the same meshing issue.

Unlike more recent Kato locos, these don't seem to have springy metals trips contacting the metal "nubs" in the truck sideframes, so the nubs are contacting the metal frames directly.  If those nubs are too tall, that could cause the truck to sit too low in the frame, and that could cause the meshing issue.  But I would not attempt to file those nubs down. I would carefully examine the trucks to see it they are assembled correct.

[thomasjmdavis]

A chassis I picked up on eBay years ago (very cheap, no complaints) made some ugly noises and it turned out it was missing the end bearing on the worm shaft.. Replaced that bearing, and problem solved. I suspect the former owner had disassembled it for some reason and lost the part.

[randgust]

Usually it's Peteski that throws the obvious bucket of cold logic here, but I'll risk it.

I had FOUR of the original Kato F-units, and spent an absurd amount of time painting and detailing them, as well as add custom lighting.  But man, they still had some pickup issues (they did not have pickup ears or wipers), and seemed to have 'flat wheels' that actualy screeched going around 13" curves, and actually were quite noisy for Katos.  After a good 15 years or so, I tried just ONE current Kato F-chassis I got on the cheap, and that was the end of that expiriment.  The performance difference was just so outstanding that the other three had to go, all four were upgraded.   Only catch was swapping the porthole/light inserts on the body shells.    I traded shells around and resold the original drives, fully disclosing what I'd done.  End result was rather low-cost for what I got out of it.

So if you're having issues, fish around for deals on one of the new ones, body shells do swap, they are DCC compatible, a whole lot quieter, and a whole lot better electrical pickup.

[ATSF_Ron]

Thanks, everyone.  Looks like I'll be disassembling again this weekend to have a look at the trucks and pickups.  All of my other older issue Fs have been perfect in terms of smoothness and noise, and I believe I've had them since 1996-ish.

[peteski]

Thanks, everyone.  Looks like I'll be disassembling again this weekend to have a look at the trucks and pickups.  All of my other older issue Fs have been perfect in terms of smoothness and noise, and I believe I've had them since 1996-ish.

Are those other ones  identical design to this one (or are they older design)?  The newest ones (from 2003 on) run very well. Smooth and quiet.

[jeffstri]

Are those other ones  identical design to this one (or are they older design)?  The newest ones (from 2003 on) run very well. Smooth and quiet.

Kato #176-215 was from the "original" version and had the trucks with the metal gear case (the 1st truck photo in Mark's spookshow review http://spookshow.net/loco/katof.html). A previous owner either swapped the trucks with the low-friction ones for the "revised" F7 version introduced in 1995; or swapped the entire mechanism. The "revised" version used the same frame as the "original," but had new universals and bearing blocks (the original had metal bearings, all plastic in the revised). The worms per se were the same in both versions, so the trucks could be swapped without changing any internal parts. The DCC ready versions from 2003 on have totally different mechanisms.

I have two SP F7A's (6440 and 6396) and a F7B (8295) from the original run. They ran better after installing the low-friction trucks but were still noisier than the revised version. I replaced the flywheels with ones with hex recesses so I could use hex universals, and Beardenized them by removing the inner worm bearings and replacing the outer bearings with all plastic ones. They run as smooth and quiet as a real "revised" version now.

[ATSF_Ron]

Peteski, I haven't opened up my 1996-ish versions in quite a while, so I dunno.  But I know I got them new.  Pretty sure I bought them from BLW.  You got me thinking, so I may end up having a look at some point.  Hard to tell without pulling things apart, and these are a bit of a pain to open up with that front coupler and all...