Lima not pulling skin off rice pudding

[class25]

Hello, I have various working Lima loco abs dmus but 3 class 37 chassis I bought back in the say can’t pull a train. Motors works loco crawls couple up a train and it wheel spins and not makes no progress. Finally looking at these after over 20 years, not previously run. Have added weight, cleaned and oiled. Extra pick ups next. Has anyone dealt with this issue before? 

[APOLLO]

Check / clean / replace the traction tyres, they're probably loose and spinning on the wheel.

 

Brit15

[87023Velocity]

3 hours ago, APOLLO said:

Check / clean / replace the traction tyres, they're probably loose and spinning on the wheel.

 

Brit15

Yes, had this on 2x Lima 3 car class 101 DMUs which had not been used for 13-14 years, the power car would not pull the 2 trailers. The last time they ran was at the Wigan Exhibition in 2004 without problems, stored in loft till around early 2018, then whilst testing ready for Wigan 2018 I had the same issue as you mentioned and what Brit says. Replacement traction tyres fitted and good as new.

 

Simon

[class25]

Thanks for your help guys. I’ve changed the tyres on one of the locos but it’s still pretty weak. Think there’s also a problem with trailing bogies being too light; now weighted. 
I’ll try the rest tomorrow. Compared to my other Lima locos these 3 are very disappointing, no issues at all elsewhere with the 31’s/33’s/47’s. 

 

[33C]

Are you using the correct tyres? Lima pattern tyres for the 37 come as a small, dark looking washer and have to be stretched over and centred properly in the groove. Adding more weight stresses the motor. As an aside, are the wheels actually turning on the track? The axles could be stripped in the wheel......or the drive cog on the armature.........

[DK123GWR]

You might also like to consider using wheels without traction tyres, such as those provided by Peter's Spares. Adhesion could be recovered through additional weight (force=coefficient of friction x normal reaction force - removing traction tyres reduces the coefficient of friction; the normal reaction force is the mass over the driven wheels x 9.81). This will come with the benefits of less dirt accumulating on wheels and track (traction tyres are a major source) and would allow you to fit additional pickups if necessary at a later date.

[class25]

Many thanks! I aim to be seen with a soldering iron later adding pickups. 
I converted these 3 into 50’s but because of their poor adhesion never used them. Will report back, thankyou all for your advice! 

[SamThomas]

In the past I've had a couple of Fleischmann BR614 DMS that have the power bogie at the cab end of a 3-car unit. Even when everything was in order these could struggle a bit but I found that they were better with the power bogie at the end pushing. (OK for me as I only tend to run in one direction).

 

Turning to Diesel/OHE locomotives with the power bogie at one end just load it up with weight ? Actually no, the weight needs to be concentrated as much as possible over the driven wheels - any additional weight over the non- powered wheels simply compounds the original issue with "grip" & the length of the train the locomotive will handle..

 

Again, with some locomotives with the power bogie at one end I've often found the performance better with the power bogie at the rear.

 

On power bogies that have 2 traction tyres mounted diagonally it may be worth trying them both on the same axel "pushing" so that any weight transfer on applying power concentrates on the traction tyres wheelset. Again, only useful for one direction running.

[John M Upton]

Clean wheels, service and lightly oil gears and bearings, add additional pickups to trailing bogie if not already fitted, replace traction tyres, check Lima's comedy wiring and soldering - replacing as necessary and finally, ADD LOTS OF WEIGHT.

 

Did all this to a Lima ARC Class 59 back in the day, after which it could pull twenty five PGA's loaded with sand with no trouble whatsoever. 

[Halvarras]

14 hours ago, 313201 said:

If I may, could I recommend the addition of pickups at the non powered end for the insulated wheels, these when wired to the motor bogie will provide extra pickup for the side of the motor that picks up from the right hand rail if looking at the loco from above at the motor end.

 

I did this modification to my lima 37 before it threw a cog which went awol and the result was much smoother running and for even smoother stopping and starting after adding the right hand pickups at the non powered end you could convert the motors for much better running with cd drawer motors.

 

I came up with a novel (I think) and possibly unnecessarily complex extra pick up solution for my four Westerns and two Brush Type 4s - I turned the middle axle in each bogie around and put a self-sprung pick up on that, formed from a single piece of nickel silver handrail wire inserted through one hole drilled through one side of the inner bogie frame and two through the other......a little difficult to describe, see if you can work out the shape of the wire..... This added extra wiring and I had to be careful not to cause a short circuit within the bogie - connecting the new pick up directly to the existing one would have been simpler and create the same number of power-collecting wheels per side, but it spread the pick up 'footprint'. I just had to remember on my DC layout that the whole loco had to be within isolated sections!

 

3 hours ago, SamThomas said:

Turning to Diesel/OHE locomotives with the power bogie at one end just load it up with weight ? Actually no, the weight needs to be concentrated as much as possible over the driven wheels - any additional weight over the non- powered wheels simply compounds the original issue with "grip" & the length of the train the locomotive will handle..

 

Hah! Your comment reminded me of something way back, must have been late 1967 or early 1968 - I bought a Tri-ang Hornby Hymek when they first came out, and so did a friend down the road. I had a layout with steel Super 4 track but his dad had built his with Peco nickel silver rails - so the 'Magnadhesion' feature didn't work. His dad was correct in adding extra weight, but even the 14-year-old me with less than two years' railway modelling experience realised that placing it over the trailing bogie wasn't the answer........I only realised what he'd done when his Hymek began sitting at a strange angle due to the pinpoint axle ends drilling through the trailing bogie's bearings! This was a common problem with T/H rolling stock back then, caused mainly by imperfect axle pinpoints revolving in plastic. He had inadvertently speeded up the process!

[d00m]

My Lima 101 DMU was also very poorly after storage. After investigating, it turned out that the magnet in the motor was very weak. With a little surgery, I added a Neodium magnet to strengthen the original. It now runs like a dream.

 

[cypherman]

Hi,

Might I also suggest swapping out the old Lima motors for the new CD motors. They work so much better and are more controlable.

[DCB]

The Lima 37 is pretty heavy as standard. Does it still have its lump of Iron amidships?..   I had to remove mine to allow space for batteries but I added lead flashing in an arch over the motor and lead strip in the nose an they will pull 6 bogies up a 1 in 14 with only one traction tyre fitted.  The idler gears wear and sometimes de mesh which stops an axle driving and cripples the performance,  Mine have one power bogie and CD motor conversions and the motor change made zero difference to the haulage, it did make a huge difference to the performance needing only 4 AA batteries for a higher speed than 6X AA gave with the Lima Pancake.   Loose or oily traction tyres also affect pulling powe.r

[John Tomlinson]

If you really want some grunt from the loco then buy a second power bogie (look on ebay or try Replica Railways) and fit that.

 

Any weight already there or added will improve adhesion as both bogies are powered.

 

Otherwise the loco should work OK provided the tyres are fresh and properly fitted, and there isn't a defect in the motor such as a weak magnet.

 

John.