SQ4 - a little investigation

 Of course, a broken motorcycle can’t be left for too long, especially when your daily rider has been persuaded from your grasp.

I was investigating a few problems, possibly associated

• There was a carburetter leak, or possibly flooding 
• The battery indicator was showing far too much red, considering the 60 miles the bike traveled yesterday 
• The bike refused to start twice yesterday, needing pushing to the top of a hill and roll-starting 

Putting the CTEK on the battery had it charging normally, but it was very flat:

But why so flat? According to the ammeter, the battery does charge and indeed, it was charging on the way home. I did notice the ignition had been left on as Tom had complained the the engine wouldn’t idle and it had died when he arrived. I currently believe this has more to do with the battery than anything else.

There is no leakage from the battery with the engine not running and you can measure normal currents with lights on, though with the LEDs fitted to this bike these are minimal. The ignition circuit draws 400 mA without the engine running - I think it would be a good idea to try this with the engine running.

I've also realised that the red spot ammeter doesn't show very much deflection at all - I calibrated the one on the Huntmaster against my bench power supply and there is a lot more movement. I wonder if the Square Four has a 30-0-30 ammeter.

A simple test with a 35 watt bulb revealed that the ammeter appears to be 15-0-15 - while I was doing this test the multimeter was reading 5 amps.

As a first step towards sorting the fuel leak, I removed the drain plug/main jet holder and finding no new fibre washer of the right size, sealed it with a wipe of Threebond 1215. That fixed the leak, and there is no evidence of flooding. 

Amelia started first time like she always does.

As to the idle, I don’t know yet as I haven’t got it warm enough to close the bi-starter.

Model A - Lucas E3 dynamo

So what's next? With the kickstart done and the gearbox back together, my plan is to reassemble the primary drive to get the bits off the bench, and move on to the front forks - a big unknown. They didn't have bushes in 1930, so we are looking at a machining job at home or away. To get there though, I have rebuilt the clutch and next is the primary chain and covers, which just need paint. I'd like to reassemble the dynamo and it's drive, but it's toast. I could either:

1. leave the dynamo in a box for a few months and get on with other things
2. reassemble it mechanically (the body needs replating)
3. Fully restore the dynamo

I've got no zinc plating chemicals, and I have a long list of FH bits that need plating which i don't really want to get into right now (and as of this afternoon, my son has taken the Huntmaster and left me with the Square Four which won't idle...); I don't want to leave the dynamo bits in a box for months, so we will go for option 2. I've also seen at least one picture of an E3 dynamo with a painted body - and I've seen another picture of a 1929 bike which made me realise that you can't really see the body when it's mounted on the bike!

Here's a photographic survey of the dynamo:

In the picture above you can clearly see the damage done to the armature - it's thoroughly bent and unrepairable. Notice that this early E3 has the magneto type open ball bearings and the taper fit for the driving sprocket along with the male thread for the retaining nut. Characteristically, the armature is 157 mm long. Putting all this together enables us to purchase a new armature for this 36 watt dynamo.

I've ordered this repair kit from Rex's Speed Shop which will include the proper bearings:

As I may have mentioned, this is just going to be a photographic survey for future use. Here are some views of the dynamo body and the commutator end casting:

Close up, we can see that the other dynamo and casting has been a victim to the side swipe that this bike has suffered - there is a crack in this end as well. It looks repairable though:

 

SQ4 - a ride out

 My son made a surprise visit today to borrow one of my CTEK battery chargers. He's not seen the Huntmaster yet and we agreed that I would ride with him halfway home so that he could have a go on it. He was very pleased with it.

However, when he arrived on Square Four he was complaining that it wouldn't idle. I noticed that he'd left the fuel on and the ignition on, and the battery condition light was showing red. I got it started by bumping it down the hill and rode it to North Walsham; it was okay ish but it obviously wasn't happy at low engine revs - but it was charging.

After a bit of a chat at the North Norfolk Motorcycle Museum, I left to go home but it wouldn't start at all - the carburettor was dripping and the battery condition light was still showing red which suggests the battery is not holding a charge. Again I'd left the fuel on, so maybe it was overflowing and the float valve is not working properly, or maybe there's a leak. 

Eventually I got it started by rolling it downhill and and rode it home like a bat out of hell at up to 60 miles an hour. It was charging, and going fine and I got home safely though the front brake is a lot worse than the one on the Huntmaster. 

I put it on the battery charger when I got home and the battery condition light showed red for several minutes, which is unusual - normally if I put it on charge it will go to green straight away. After a couple of minutes it went to solid green which means it's charging or fully charged.

There's something wrong here.