LTechG Posted March 17, 2015 Share Posted March 17, 2015 Hi, I have just built a storage area for my layout, which involves a single slip and 3-way point. I have a class 37 Lima loco which really bumps through the frogs on the single slip. Both points are Peco code 100. The loco goes through the 3-way point ok, but really struggles through the slip. Although it does go through it seems to rise up when the drive unit enters the frog as though the flanges are too deep. Wondering if there is any way of replacing the wheels with a finer profile, and if so what those wheels are. regards Barry Link to post Share on other sites More sharing options...
royaloak Posted March 17, 2015 Share Posted March 17, 2015 check the back to backs on the axles, it sounds like one (or more) is a bit tight. If you don't have a gauge try looking along the 3 wheels to see if one wheel is out of line, if it is ease it along the axle so it in line with the others. It might be that they all need spacing out a little (and just a little) because Lima locos do tend to be a bit tight on their back to backs. Link to post Share on other sites More sharing options...
DCB Posted March 18, 2015 Share Posted March 18, 2015 My Lima 37s are fine through code 100 Peco points, the back to back needs to be somewhere around 14.2 to 14.5 mm, I make gauges out of a piece of wood carefully filed and checked with a Micrometer. If the traction tyres are worn or missing the flanges will bottom out but I would suspect the centre wheel set, maybe leave it out and see if it cues the problem, My 37s have modified motors like Model Torque and the centre wheel flanges foul the motor but not on 2ft radius points Link to post Share on other sites More sharing options...
LTechG Posted March 18, 2015 Author Share Posted March 18, 2015 Back-to-back spacing has been set with a "00" gauge spacer but that introduces another problem. Because the wheels had to be opened out slightly, the gear meshing of the final axle to the intermediate gear is now loose enough to allow the gears to come out of mesh, so the motor spins merrily with no drive to the axles. Is this normal?? I suppose I can overcome it by installing a very small washer on the side of the axle that doesn't have the drive gear, thus "pulling" the gear back into mesh, but wondered if there was something more fundamental wrong. Has the intermediate gear been "thinned" over time to the extent that the gears don't mesh correctly perhaps. Any advice gratefully accepted. The problem is slowly driving me nuts!!! Regards Barry Link to post Share on other sites More sharing options...
DCB Posted March 25, 2015 Share Posted March 25, 2015 I am afraid you need the feeler gauges and a micrometer to establish what size shim washers you need to get the back to back right on the driven axles and keep the gears in mesh. Put the washer on the non drive gear side It might be too much hassle for what is now an obsolete design of power bogie Link to post Share on other sites More sharing options...
RMweb Premium Clive Mortimore Posted March 25, 2015 RMweb Premium Share Posted March 25, 2015 Back-to-back spacing has been set with a "00" gauge spacer but that introduces another problem. Because the wheels had to be opened out slightly, the gear meshing of the final axle to the intermediate gear is now loose enough to allow the gears to come out of mesh, so the motor spins merrily with no drive to the axles. Is this normal?? I suppose I can overcome it by installing a very small washer on the side of the axle that doesn't have the drive gear, thus "pulling" the gear back into mesh, but wondered if there was something more fundamental wrong. Has the intermediate gear been "thinned" over time to the extent that the gears don't mesh correctly perhaps. Any advice gratefully accepted. The problem is slowly driving me nuts!!! Regards Barry Hi Barry No need to be to technical, place a washer on the non-driven side as you have suggested. Just ensure that the back to back is OK and the slop is taken up. In the past I have had to do this with Hornby pancake motors when opening out the back to back but never a Lima one. A couple of my class 25s still have 40 thou plastic card washers put in place over 25 years ago. Link to post Share on other sites More sharing options...
LTechG Posted March 27, 2015 Author Share Posted March 27, 2015 I'm intrigued by the comment about the drive unit being obsolete. Is there a drop in replacement for this type of motor bogie then? I would love to upgrade my several Hornby Class 25's, 37's and HST's if there is? Regards Barry Link to post Share on other sites More sharing options...
RMweb Gold Scottish Modeller Posted March 27, 2015 RMweb Gold Share Posted March 27, 2015 Hi Barry, A lot of the older models have drive units that are, technically 'obsolete'. That does not mean that they will not work! With care and maintenance - they will continue to work. The current motor units from Hornby will not just 'drop in' to replace the older ones. If you look online for Peters Spares - you will find spares are available. Following on from what you (and Clive) suggested about putting a shim washer ain to pack out and keep the drive working - this will work - in most cases. If it still does not work - then look at getting some spare idler gears and doubling them up to take up the slack. This will not work instantly and you may need to thin them down before it does. If all else fails - there are still replacement motor units available complete with gears. Thanks Link to post Share on other sites More sharing options...
sdw7300 Posted March 30, 2015 Share Posted March 30, 2015 Hi I've bookmarked this page http://www.diesel-trains.co.uk/Lima_replacement_motor_kits.html after reading another thread. I've not tried one myself yet but might need to in the near future. Cheers Link to post Share on other sites More sharing options...
RMweb Premium Clive Mortimore Posted March 30, 2015 RMweb Premium Share Posted March 30, 2015 Hi I too have a Lima 37 and was wondering what the best replacement would be so I can eliminate the pancake mptor completely and give it smmother and quieter running and better traction. The Lima 37 is so out of shape and the body side grilles are too small why bother. By the time you have sourced a drive, fitted it etc. you might as well buy a secondhand Bachmann or Vi Trians 37. Both of which are better models and run better. Says the man with a fleet of Tri-ang 37s running on Lima chassis. I do have some Bachy and Vi type 3s, a scratch built one and 2 running on Tri-ang chassis with modified bogie sides and tanks from Lima locos. Link to post Share on other sites More sharing options...
DCB Posted March 31, 2015 Share Posted March 31, 2015 Hi Barry No need to be to technical, place a washer on the non-driven side as you have suggested. Just ensure that the back to back is OK and the slop is taken up. In the past I have had to do this with Hornby pancake motors when opening out the back to back but never a Lima one. A couple of my class 25s still have 40 thou plastic card washers put in place over 25 years ago. You have to be technical as there is a very limited number of times you can press the wheels on and off the axle before the wheel becomes a loose fit, hence my advice to check the gap with feeler gauges from a car spares shop and check the thickness of suitable washers with a micrometer which should cost all of a tenner second hand, which is probably cheaper than a replacement power bogie Link to post Share on other sites More sharing options...
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