Lgb Uintah Mallett - Slow Running

Orgiva

Orgiva

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I have an old one of these; the dates on the motor covers is 1994. I bought it several years ago but (for reasons of not having a railway to hand) never ran it until very recently. On first trying to run it, it would be deadly slow and very jerky, eventually grinding to a halt. Yesterday I cleaned the wheels and wheel contacts and now it runs pretty smoothly but painfully slow, even at 18.5 volts.

Any ideas as to what may be causing this slow running?
 
stockers

stockers

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Grease is not usually a problem but if its been static for that long i would whip off the base plates and have a look. Mind you don't move the axles relative to the gearing though.
A tiny bit of grease goes a long way - too much causes other problems.
 
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PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Check the grease has not broken-down a little, and left oily residue over everything..
Check back faces of wheels are clean..
Use a meter to check for continuity between all wheels and skates down each side of loco..

Also, if it has never been run.. It probably needs running for a few hours to loosen everything up.
 
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kim

kim

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Whilst you have the base plates off look at the lugs for the 1st and 3rd axles, they should have a flat bottom that pushes the axles up into the gearbox to engage the drive properly. If the lugs are round at the bottom the drive is not engaging properly.
Forgot to ask, does everything turn by hand nice and smooth?
 
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stockers

stockers

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Most worm drives don't turn by hand very easily.
 
kim

kim

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Most worm drives don't turn by hand very easily.
I've found that the Sumpter mallet and Moguls turn easily by hand Alan - mainly what I run - as long as the gears mesh correctly and quartering is correct etc. I did a complete rebuild on one of my Sumpters with new wheels, motors, gear box and base plates with new Massoth electronics and sound etc. Wheels turn easily by hand. If the wheels don't turn by hand then I have found that it is a sign of base plate lugs and intermediate gear wear.
Kim
 
Orgiva

Orgiva

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Kim, let me check and I'll get back to you.
 
stevedenver

stevedenver

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Motor me thinks. How is current draw?
Just had the same issue with a mallet, ran slow, drew 4-6 amps. Replaced one motor, which seemed like new, now running fine.
 
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Neil Robinson

Neil Robinson

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Motor me thinks. How is current draw?
Just had the same issue with a mallet, ran slow, drew 4-6 amps. Replaced one motor, which seemed like new, now running fine.
I once read somewhere that this isn't uncommon and the front motor is the usual culprit. The suggestion was that it was liable to contamination from smoke fluid. Personally I have no evidence to support or deny this.
 
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stockers

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An interesting post Neil. I too have seen this possibility proposed. Looking at my LGB Mallet (the German one), you are not going to flood the motor from the chimney unless you wash the blinking thing.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
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Can't see it myself..
Perhaps there is a route the fluid will tend to follow?? - Will move 'along' edges, so can move sideways, I suppose?
 
Orgiva

Orgiva

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Yes! Today I dry ran it on a table and checked the amp draw and the continuity across the wheel and contacts and inside the motor boxes. The amp draw was about 1.25 across both motors and the continuity through wheels and contacts was ok. Also, I couldn't turn the wheels by hand; I didn't want to exert too much force.

What I haven't checked was the 1st and 3rd axle lugs. I'll look at his tomorrow.

The engine still runs very slowly but has moments of quicker running. It suggests some electrical connection problem somewhere; I'll keep investigating.

Mike.
 
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dave snape

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I bought a Uintah mallet,in 1996 ,from the usa. It goes at about a scale30-35 mph, which is about what the real loco would do.I have recently changed it to radio control, and taken all the pickup plungers out. This has put another 10-15 mph on the top speed. When I bought it back, on the plane,I was worried about having to pay import duty on it but the woman,who put the box through the scanner,at Denver airport,said " Oh you got your little boy a toy choo choo"! Yes I said -he likes choochoos.
 
KeithT

KeithT

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Trains of this scale are classed as "toy trains" for import purposes so no Duty however, you are fortunate that they did not charge you VAT.

I bought a Uintah mallet,in 1996 ,from the usa. It goes at about a scale30-35 mph, which is about what the real loco would do.I have recently changed it to radio control, and taken all the pickup plungers out. This has put another 10-15 mph on the top speed. When I bought it back, on the plane,I was worried about having to pay import duty on it but the woman,who put the box through the scanner,at Denver airport,said " Oh you got your little boy a toy choo choo"! Yes I said -he likes choochoos.
 
KeithT

KeithT

Hillwalking, chickens and - err - garden railways.
24 Oct 2009
12,977
1
Nr Manchester
This is a v long shot having read the posts but if you are running MTS have you accidentally pressed button 8? That will reduce the power to half.

I have an old one of these; the dates on the motor covers is 1994. I bought it several years ago but (for reasons of not having a railway to hand) never ran it until very recently. On first trying to run it, it would be deadly slow and very jerky, eventually grinding to a halt. Yesterday I cleaned the wheels and wheel contacts and now it runs pretty smoothly but painfully slow, even at 18.5 volts.

Any ideas as to what may be causing this slow running?
 
Orgiva

Orgiva

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Alpujarras
Keith, I'm not running MTS (yet) but thanks for the tip.
 
stockers

stockers

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Nr. Ashford, Kent. England.
This is a v long shot having read the posts but if you are running MTS have you accidentally pressed button 8? That will reduce the power to half.
Well remembered Keith. Little details like this can go unnoticed and be really annoying.