Wrenn 2-8-0 seized axle

[andyman7]

A recent auction lot included a clean but unboxed Wrenn 8F that failed to work when bench tested - buzzing but no movement. Investigation has revealed that the issue is a seized non-flanged driving wheelset - just one  as seen in the middle of the picture (the others have free play so seem fine), which can just be turned by hand but is very stiff. I'm much more familiar with Triang chassis so rather than get the motion and wheel off by trial, error and brute force I'm asking for advice first. Triang valve gear can easily be unscrewed but Wrenn/HD are attached by little rivets. Can these just be prised off? Any tips? 

 

Once the motion is off my approach would be to lever a wheel on the seized wheelset off, get the other half and axle out and try and work out what's gone wrong. Hopefully a little cleaninng and reaming if needed can sort things out. Again, any tips would be appreciated. Thanks!

 

Edited November 24, 2020 by andyman7
Spelling

[Il Grifone]

Unfortunately the rivets are peened over on the inside of the wheel, so all of the wheels have to come off. They are splined, so go back on again without quartering problems. The insulated wheels will come off with a suitable lever (screwdriver  ) without much trouble.

The problem is almost certainly years of dried up crud (She is at least thirty years old!)

 

However first check the motion is free as the connecting and eccentric rods look bent (the former should be cranked just sufficiently to clear the leading crankpins), but it could be the angle of the photo.

[stewartingram]

Instead of removing wheels by, presumably, levering off with a screwdriver, use a pair of electronics pliers instead.

The screwdriver will lever the wheel off at an angle; pliers, inserted either side of the axle, lever the wheel off either side of the axle thus keeping it straighter.

Stewart

[Ruffnut Thorston]

When we received our Hornby Dublo 8F, it too was seized, the axles binding.

 

What we did was to remove the motor, which was then tested and serviced. This was the earlier half inch motor, not the Ringfield motor.

 

The pick up plates and wiring were also removed I seem to recall, leaving just the wheels and motion and the chassis block.

 

Then using carefully applied penetrating and easing oil onto the axles, the chassis was pushed up and down a length of straight track, so all of the wheels were moved at the same time.

 

This oiling and pushing continued for some time, the residue of the oil and crud that came from the axles was cleaned off frequently.

 

In the end the axles freed off totally, and the chassis would roll down the track if the bit of board that it was attached to was tilted.

 

Finally, the loco was reassembled, and has been a good runner.

 

 

 

 

Edited November 24, 2020 by Ruffnut Thorston
Added photo

[Il Grifone]

I forgot to mention - lever off the uninsulated wheel, not the insulated side. That way avoids straining the plastic bush; the metal is strong enough to resist all but deliberate attempts at damage.

I have to admit using the oil/solvent method. White spirit or similar will remove most crud, but dismantling is necessary in severe cases. Obviously the gear needs to be freed off by loosening the two grub screws, taking care not to lose them....

[andyman7]

Thanks, this is really helpful. The motor and pickups have already been removed, so I will try to free up the axle as suggested with white spirit but if that fails will remove the wheels as per method outlined.

[Nearholmer]

I was just about to suggest what Ruffnut has suggested.

 

Assuming the valve-gear is now all nice and straight, the problem is very likely to be glue-ified oil in the bearings, and it is a really good idea to attempt to clear that chemically, rather than resort to wholesale dismantling as the first option.

 

I'd leave the white-spirit (paraffin or diesel is very good for this job BTW, just a couple of tiny drops) plenty of time to get in and work, a couple of days maybe, and if it does succeed, keep gently flushing and cleaning with it, because you really want to try to wash out all of the old gluey oil.

[andyman7]

Thanks, I'm with you on keeping to the minimum amount of dismantling so am trying to free up as suggested first.

[DCB]

I had this on a H/D R1 chassis on a Wills 97XX Tank.  The leading and trailing wheels were seized just about solid.  I turned it upside down and dribbled 3 in 1  oil onto the axles and worked the wheels backward and forwards using a lot of pressure, once the started moving they soon freed up. Centre was also tight but not so bad. 5 minutes later it was going like a rocket.It had had almost no running from new.

I would unsolder the pickup lead and  remove the motor and pickups and oild the axles.   I would not remove the wheels unless absolutely, and then remove the INSULATED wheels.  New bushes are available if they come loose but my experience is the NON insulated work loose if they are disturbed. Likewise the 2 rail crank pins are not peened over, 3 rail are, and can work loose in Non insulated wheels. The Wrenn  8F benefits greatly from lower gearing but that is advanced bodgery. Best left to another thread.

[andyman7]

I've applied the white spirit and within five minutes it's all freeing up beautifully, with no need to remove any wheels. I'll let it penetrate but I'm very grateful for the help and advice. I'm pretty deft with Triang locos but that was based on 35 years of tinkering and a fair few accidents whilst learning the way. It's so much easier to get advice from those who have gone before!

 

[andyman7]

18 minutes ago, DavidCBroad said:

I would unsolder the pickup lead and  remove the motor and pickups and oild the axles.   

On the two rail version it's possible to get the pickup out without unsoldering, it can be unthreaded through the pickup plate and chassis. As you and others suggested (and based on my own previous experience) its really important to work on getting a free running chassis before any pickups or mechanisms are added - if there is drag or resistance before any of these are added, it isn't going to get any better!

Edited November 25, 2020 by andyman7

[Ruffnut Thorston]

It’s great to hear that things are working out.

 

 

[Il Grifone]

If it is absolutely necessary to remove the driving wheels, pulling/levering from the non-insulated side will avoid possible damage to the bush (as stated Wrenn axle bushes are still available on eBay). The axle will pull out of the bush, as the fixing is more secure metal to metal.