Help with BLI E7 (Partial Solution update)

[C855B]

Yes, the profile of Kato wheels look great. Makes me wonder if there is a possible NWSL retrofit to get the 36", or even possibly doing this by taking apart FVM wheelsets. Hmmmmm. :chin-stroking:

What I find quite interesting is while Es had 36" wheels, contemporary Fs and GPs had 40". I'd be interested in the engineering logic.

[nkalanaga]

So would I.  Smaller wheels give better tractive effort, at the expense of lower speeds, for the same motor speed and gear ratio.  If anything, it seems that passenger diesels should have larger wheels, as they would need speed more than TE.

[Missaberoad]

I believe it was due to the traction motors... the F units (and later hood units) had physically larger traction motors that required 40" wheels for clearance.
In fact when EL changed their E8s over to freight service they changed the traction motors and had to change to 40" wheels.

Not 100% certain but this is the only explanation I could find and it makes sense...

[nkalanaga]

Ryan:  Yes, that does make sense.  36 inch wheels were already in common use on passenger cars, so it would make economic sense to use the same size on the locomotives.  Then, once it became apparent that freight diesels required larger wheels to fit the larger motors, locomotive shops wouldn't want to keep two sizes, so 40 inch became the standard.

Don't some of today's units use 42 inch?  Is that for the same reason, bigger motors, or is there another reason?

[peteski]

@Cajonpassfan, I think you're right that they should be 36" wheels, but they look better than the stock wheels to me, even if oversize:

There (sort of) is a solution to this:  Kato replacement passenger wheelsets. Those are 36" and the axles should also be direct fit into the plastic axle tubes.

 The problem is that while new Kato passenger cars do come equipped with these wonderful thin-tread low-profile wheelsets, the spare sets Kato sells are still the older design (wider tread and deeper flanges). Still, they probably still  look better than stock BLI wheels.

BTW, did someone actually measure the BLW E7 wheels?  IIRC Kato E8s and even the F7s use their standard 40" wheelsets.

[Cajonpassfan]

@Cajonpassfan, I think you're right that they should be 36" wheels, but they look better than the stock wheels to me, even ...

DFF

Dave, absolutely, I'm with you on this. And given our oversize flanges, larger wheel diameter always looks better in proportion to the flange. And besides, what's 4" between N scale friends anyway... 
Otto ak.

[atsf_arizona]

Haha!  I've got it running really well now, but you'll never guess what I did.

I had four Kato #932090 wheelsets that I got from @Chris333 leftover after upgrading the wheelsets on my Atlas SD50s.  So, I tried replacing all six wheels on the rear truck.  Please note that I reused the plastic axle from the E7, since the gear on the Kato axle is not centered as the BLI gear is.  The wheels are a perfect fit in the BLI axles!  Not only do these wheels perform better, but they look 100% better, too!  Sadly, I am two axles (four wheels) short to replace all of the wheels on the front truck, but I need some more Kato wheels to update my IM SD45-2 anyway.

DFF

Hi, davefoxx,

This is excellent place to buy the Kato 932090 wheelsets: 

http://www.modeltrainstuff.com/Kato-N-Low-Profile-Geared-Wheel-Sets-p/kat-932090.htm

It's the best price I've found, and (as of 12/29/16) MB Klein has a whole lot of them in stock.

Do you have any pics/tips/hints of your replacing the BLI E unit wheels with the Kato wheelsets?   I'd like to note that as such
in my documentation of replacing BLI wheelsets here:  http://www.pbase.com/atsf_arizona/bli_n_pa1_wheelset_replace&page=all

---------------------------
JS update:  I see in your post #2870 in https://www.therailwire.net/forum/index.php?topic=25551.2870  and
now #37 below, that this wheel swap wasn't successful due to louder noise with the Kato wheelsets.
---------------------------

[davefoxx]

Hi, John,

Actually, after reading that other thread about driveline noise, I became worried about the extra drag possibly caused by the Kato wheelsets with the longer axle points.  So, I put the BLI wheelsets back in.  Because I was able to scavenge extra wheel sets from an unused B-unit, I did not put the wheels with traction tires back in.  The locomotives run much better.   The end result is that I'm back to your solution- ditch the traction tires.

DFF

[Cajonpassfan]

I have two powered BLI E7's and one unpowered B unit. They run fine, but I too was thinking about ditching the traction tires to improve pickup, but was concerned about loss of adequate traction effort because one of the units has significantly less traction. So I opened up the trucks on the powered B unit, and lo and behold, the inside axle on one of the trucks is not powered: the intermediate gear is simply MIA. I bought it new in 2006 and never opened it up before. Time to contact BLI ....

Funny thing is, I've run these on and off since 2006, and never noticed this problem before. They are actually the early "Precision" units equipped with Loksound decoders. If I can get the parts, time to do a "full servicing".
Otto K.

[davefoxx]

@Cajonpassfan,

I think I see your missing gear deep inside the truck.  Look close and see if that's correct.

DFF

[Chris333]

Yeah right between the left and middle wheel you have a small gear that is turned about 45 degrees.

[Cajonpassfan]

Thanks guys, embarrassing 
Sometimes you can see in photos what's not obvious with the naked eye. Goes for building models, too.
I should've looked at the photo before posting it...
Otto K.

[Santa Fe Guy]

Great pick-up guys but look at the offset on the centre wheel-set gear. Not good at all.
Rod.

[davefoxx]

Great pick-up guys but look at the offset on the centre wheel-set gear. Not good at all.
Rod.

That's mainly because the sideframes have been removed, allowing the wheel sets to slip sideways a little bit more than they can when the truck is put back together.

DFF