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Does anyone know how to cure the running problems that Bachmann split chassis locos suffer from ie that jerky limp??

I have a B1, V3 & a J39 that have the older split chassis. The J39 is not too bad but the B1 & V3 are awful. The B1 settles
down after an hours running but if its then put away & used again a week later it needs another hours running in!! The V3
will not run smoothly regardless of what I do!

Anyone have any ideas? These are 3 nice locos that I have but are not really useable which is a shame.....
 

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QUOTE (theallendalebranch @ 24 Mar 2009, 10:01) <{POST_SNAPBACK}>Does anyone know how to cure the running problems that Bachmann split chassis locos suffer from ie that jerky limp??

I have a B1, V3 & a J39 that have the older split chassis. The J39 is not too bad but the B1 & V3 are awful. The B1 settles
down after an hours running but if its then put away & used again a week later it needs another hours running in!! The V3
will not run smoothly regardless of what I do!

Anyone have any ideas? These are 3 nice locos that I have but are not really useable which is a shame.....

I have this problem too with a B1

I bought one from a show and it was awful, really bad, so I returned it to where it was bought from, they sent me another.
At first it ran fine, but after a few days i found that it would be a bit jerky and required running in, and then it would be fine.
This is the case all the time now, the loco requires running in, otherwise it's jerky

It's really annoying, for now the loco is back on shed and it's duties have been replace by a K3.
 

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Hi
Remove the wheelkeeper plate and clean the axles and journals. I have a J39 that has had similar problems. A clean up cured most of the ills, still sounds like a box of spanners at times.
Bottomline the chassis is rubbish !!

****
 

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QUOTE (**** b @ 24 Mar 2009, 19:48) <{POST_SNAPBACK}>Bottomline the chassis is rubbish !!

I definitely second that after having 2 B1's and both were sent back and money refunded!

Kind regards

Paul
 

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As above, it is usually the chassis lubricant present in over-generous quantity. the white grease used solidifies on both axles and gears and takes time to loosen up with running. What I did when still purchasing these locos, was immediately clean out all the grease (retaining it in a stoppered sample tube) leaving just a smear behind. Roughly annually these locos need all the axle bearings cleaning out to remove what will now be black grease. Bachmann reccomend using IPA (iso-propyl alcohol) for this job. Then apply a light smear of the retained grease. Never had to buy any of this grease, the locos basically come with a lifetime supply onboard...

And yes, Bachmann cannot phase out this chassis design fast enough.
 

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Echo the above with the following 1) check that the con rods are not binding on the plastic wheel inserts. One would think that this would be constant but it is not. Dont really know why, but! 2) Check that the gear on the drive axle is centred between the wheels. This drove me batty on B1; J39, V1 etc. At the start of any session it would result in really jerky running then as the session went on it would become less when running at speed but was still pronounced at slow speeds. If this gear is not centred it moves to one side of the worm gear and every so often I suspect the worm gear misses a tooth. Once I figured out what it was I was able to cure all my jerky runners including one J39 that was close to going in the scrap bin.
 

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I had this problem with a Manor, and I had a different situation. It turned out that one of the stub "axles" had become detached. It was not held into the the plastic "joiner" by anything other than sticktion. Consequently, when it went round a curve, it got slightly displaced, and then limped. I simply removed it, glued it back in and it now seems to behave itself fine. I am not sure the same cure will work on a 4MT that I have with the same problem, and fortunately, I haven't had to take a B1 apart, so I don't know if it works on those.
 

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Over time most of the split chassis locos suffer some break up of the insulating muffs onto which the stub axles are a push fit. Most of mine are araldited, (A4, B1, J39, J72, V's 1, 2, 3) as this resists penetration by lubricant very well, and lasts until other components are irretrievably worn out. On the same theme as 'theakker' posted there are a number of problems with this chassis construction, and it is something of a lottery which one causes the chassis to go unserviceable. All mine have necessarily been apart to enable decoder fitting, and that's when I tackle all the defects systematically. Failure then typically occurs when most of the plating has worn off the wheel tyres, stub axles and chassis journals: pick up is then so poor even if helped with some graphite powder in the lubricant grease, that it is time to call it a day. Basically it is a short life chassis, and Bachmann practically acknowledged the fact by selling replacement chassis units; which they are now phasing out as replacement models with a conventional design chassis come through.
 

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QUOTE (34C @ 27 Mar 2009, 10:25) <{POST_SNAPBACK}>which they are now phasing out as replacement models with a conventional design chassis come through.

Can't come soon enough for me!!

Kind regards

Paul
 

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Guys, a thought has just occurred to me, and I didn't like it much. Does anyone know when Bachmann stopped using split chassis? Is there a list of when each model changed over? I was about to buy a V2 today, when I suddenly realised I didn't know which chassis it would have! It's a nightmare!
 

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QUOTE (Fireline @ 27 Jun 2009, 15:43) <{POST_SNAPBACK}>Guys, a thought has just occurred to me, and I didn't like it much. Does anyone know when Bachmann stopped using split chassis? Is there a list of when each model changed over? I was about to buy a V2 today, when I suddenly realised I didn't know which chassis it would have! It's a nightmare!

Honestly - don't buy, by todays standards it's a poor model, like the Lord Nelson,with detail inaccuracies as well as a poor split chassis.
 

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I spayed my J39 with WD40 and so far transformed. There are concerns re WD40 attacking plastic?? As this chassis isa load of junk if it fails it will be binned so worth a try first!!!!!

****
 

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QUOTE (**** b @ 27 Jun 2009, 22:33) <{POST_SNAPBACK}>I spayed my J39 with WD40 and so far transformed. There are concerns re WD40 attacking plastic?? As this chassis isa load of junk if it fails it will be binned so worth a try first!!!!!

****

NOOOOOOOOOOO !!!
Not WD40 - YUK sling the stuff away, it shouldn't be anywhere within 100 yards of model railway equipment, it will ingress into the motor and totally (m)uck up the motor brushes.It also is a good dust collector for axle bearing surfaces.
The best cure for a Bachmann 'limp' is build a new Comet chassis, or similar.
 

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7 or 8 years ago all these split frame chassis loco's were probably the most reliable performers in my stud of loco's. They were always preferable to a tender drive
and are capable of suberb running once tinkered with.

There's quite a few bounues with this chassis.
(1) current collection is excellent as it's conducted via the wheels and through the two halves of the frame to the motor.
(2) weight, this generally is a nice heavy chassis, so they have good pulling power.
(3) one of the reasons why I hardly ever had the problems listed by other users is that I always broke the chassis down and fiited a decoder fitted. At that time
removal of burrs and attention to lubrication was under taken.
some of the chassis are prone to problems, if I remember rightly the std class 4 always seemed to wear out due to failure of a small screw fitting on the motion,
but the Ivatt tank is simply a real gem, with current collection even on the front bogies, it's well worth a look at even now. Yes they are a bit more difficult to get right, but there's a lot of satisfaction waiting for you, once you've taken the time to get to know the product.
 

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I would echo those comments. Not having had a 4MT and Ivatt 2MTT (unsuited to my modelling scenario) it is interesting to see them compared; similar differences exist elsewhere in the range.

The J72, A4 and V1/V3 have generally been good as received and with 'tweak' treatment only improve. The A4 can have pick ups added very simply to the split chassis leading bogie, and the tender wheels are split axle also; the V1/V3 needs the rear bogie wiring added for all wheel pick up. As these mechanisms wear out, the bogie and tender wheels go toward other locos to provide enhanced drag free pick up on these. All three are decent models in appearance terms, the A4 the most significantly dated, no real competition for the very fine Hornby body shell, although the wheels and motion look far more like what Doncaster built than the more generic parts used by Hornby.

The B1 and J39 are generally decent, both can be a little noisy and lumpy before fettling, but this done will perform very well. (The A4 tender wheels are often to be found under the tenders of these locos providing enhanced pick up.) Both have good body shells, the B1 a tribute to the fine tooling originally specified by Replica: when this model first appeared it was the best body on a RTR OO steam loco, and by a country mile, and still looks well against the best current offerings.

The V2 is a dog to be blunt. It's a good job that the original was so good looking, which the poorly executed loco body shell does not quite conceal. Unfortunately the chassis is a match in running quality. Usually pretty rough, and resists significant improvement quickly returning to graunchiness after adjustment. It does though 'grind on' pretty much forever...
 

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QUOTE (bike2steam @ 28 Jun 2009, 12:33) <{POST_SNAPBACK}>NOOOOOOOOOOO !!!
Not WD40 - YUK sling the stuff away, it shouldn't be anywhere within 100 yards of model railway equipment, it will ingress into the motor and totally (m)uck up the motor brushes.It also is a good dust collector for axle bearing surfaces.
The best cure for a Bachmann 'limp' is build a new Comet chassis, or similar.

I would second that - a short term "fix" as apart from the above it will eventually dry to a horrible "gunk" with the resultant bad running again.

To say nothing of the possible long term consequences.

WD40 is fine on lawnmowers & as a penetrating oil (diesel & turps is even better), so leave it in the garden shed where it belongs.
 

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Hello all. The jerky Bachmann split chassis; This problem is predominantly present on the earlier Hong Kong made chassis rather than the later Chinese made ones. The reason is loss of wheel-quartering resulting in the notorious 'Bachmann Waddle'. The earlier Hong Kong made chassis has round wheel spigots press fitted into the round-holed axle spacers. With age the plastic axle spacers 'plasticise' (become brittle and split) resulting in the driving wheels moving in the axle-spacer = loss of quartering. The Chinese made chassis on the other hand has a larger bearing diameter allowing the axle spacer to have a larger diameter to accommodate a square spigot. A square spigot in a square holed axle spacer does not allow loss of quartering. Oh yes it does!!! This again is because the plastic axle spacer plasticises with age and splits. This is especially manifest on the axle with the gear drive. When this axle splits the split tends to continue up through the gear wheel which results in a jerky chassis with a thump every revolution of the gear wheel when the gear wheel interlocks with the intermediate gear wheel. There are ways and means of making the Chinese made split chassis into good runners even after they have 'failed' but avoid the Hong Kong made stuff like the plague (or swine flue being the current trend) as the . I run loads of Bachmann Chinese made locos (but I do undertake my little 'modifications' first) and do not have any trouble with them. They do run quite sweetly. In saying this though; you shouldn't have to modify a new chassis to get good results.
 
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