This is my first post.
Thanks to John Williams and the mods for a great forum to supplement the brilliant SOS site.
Sorry for this long essay (it didn’t start out that way) but I figure it’s better to give all the information I have to help others diagnose the problem.
A mate down here in Australia gave me his BS to fix a couple of days ago. He bought it some time ago from a bloke who did a reasonable job of restoring it, apart from the slight problem that neither the restorer nor my mate ever managed to start it. I’ve started it a couple of times by luck but can’t work out what it needs to start reliably.
I believe this is a Century made around 1960. The serial number is LLS12312.
Nice blue spark. Points look new and clean. Set at .020â€
Is this Villiers carby / Century dead?
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
Progress report: No progress.
Replaced washer on centrepiece with thin (centrepiece same height as old washer) and then thick O ring. If they don't seal, nothing will. No improvement either time.
I'm completely stumped.
Now I'm wondering if the problem is in the block, such as a blocked port. Anyone know where I can get a diagram for the block? I'd pull the head but, as I've just discovered, the nuts on the head studs are BSW or something that none of my sockets or spanners will fit.
Replaced washer on centrepiece with thin (centrepiece same height as old washer) and then thick O ring. If they don't seal, nothing will. No improvement either time.
I'm completely stumped.
Now I'm wondering if the problem is in the block, such as a blocked port. Anyone know where I can get a diagram for the block? I'd pull the head but, as I've just discovered, the nuts on the head studs are BSW or something that none of my sockets or spanners will fit.
Hello ozdog - been trying to absorb your detailed account!!!
Obviously the cracked block needs sorting out sometime, and other things need attending to, but I think at the moment your problem is all carb related, and a lot of the side issues will resolve themselves.
Basically, the spark is clearly OK - my only question here is if the magneto baseplate is in the correct position - ie is the locating screw engaged in the dimple in the crankcase?
Carb - check the if the emulsion tube is in the correct position (check the jet is clear whilst you are at it). The brass tube is located in the carb by a small screw which engages with the small ramp or cutout on the top flange which you view by looking down the piston bore of the carb. This is important to line up the compensating jet in the carb body. Check also that this jet is clear. This is in the side of the flange of the brass body. GO back to basics with your needle setting - ie just have the top of the adjusting screw flush with the piston. Most engines don't need the choke to start, so ignore playing with the choke. There may be other problems such as no crankcase pressure if the motor has been stripped and cleaned, and there is no oil around the crank bearings to form a seal. This should correct itself after you have roped it over a while and/or get the engine running. Let us know how you get on -- Rick
Obviously the cracked block needs sorting out sometime, and other things need attending to, but I think at the moment your problem is all carb related, and a lot of the side issues will resolve themselves.
Basically, the spark is clearly OK - my only question here is if the magneto baseplate is in the correct position - ie is the locating screw engaged in the dimple in the crankcase?
Carb - check the if the emulsion tube is in the correct position (check the jet is clear whilst you are at it). The brass tube is located in the carb by a small screw which engages with the small ramp or cutout on the top flange which you view by looking down the piston bore of the carb. This is important to line up the compensating jet in the carb body. Check also that this jet is clear. This is in the side of the flange of the brass body. GO back to basics with your needle setting - ie just have the top of the adjusting screw flush with the piston. Most engines don't need the choke to start, so ignore playing with the choke. There may be other problems such as no crankcase pressure if the motor has been stripped and cleaned, and there is no oil around the crank bearings to form a seal. This should correct itself after you have roped it over a while and/or get the engine running. Let us know how you get on -- Rick
Rick
Thanks.
Stator plate is in correct position. I unscrewed it to check as part of the initial general checks.
Carb internals couldn't be cleaner.
Locating screw is in correct position on ramp.
I think (hope) I've misled myself and everyone else by glossing over the crankcase cracks. As everything else had been tried I looked at them more closely tonight and got at the worst one with a Dremel. It turns out that it is a full thickness crack, about 3/4" long in an arc. The restorer had repainted the block and the paint and underlying rust / dust stuff masked it. Trusty old JB Weld has been applied. If there is a passage to a port on this side then things should improve when it's set. I'll report after it's set.
Your comment about no oil to seal things might be right, as it's been a dormant motor for a long time.
Thanks.
Stator plate is in correct position. I unscrewed it to check as part of the initial general checks.
Carb internals couldn't be cleaner.
Locating screw is in correct position on ramp.
I think (hope) I've misled myself and everyone else by glossing over the crankcase cracks. As everything else had been tried I looked at them more closely tonight and got at the worst one with a Dremel. It turns out that it is a full thickness crack, about 3/4" long in an arc. The restorer had repainted the block and the paint and underlying rust / dust stuff masked it. Trusty old JB Weld has been applied. If there is a passage to a port on this side then things should improve when it's set. I'll report after it's set.
Your comment about no oil to seal things might be right, as it's been a dormant motor for a long time.
JB weld set. Compression up about 5 psi. No idea why as I don't know where the internal passages are in the block.
No other improvement.
What I thought was exclusively fuel problems now looks like it might have been ignition problems as well. Despite numerous previous spark tests looking okay, I've now done some longer ones and it seems that there is an intermittent spark, or lack of spark, problem.
I've spun the flywheel with an electric drill to remagnetise it, with no improvement.
The problem seems to be due to someone not using the correct BS high tension lead. It's just a standard fibre HT lead with, at the coil end, the usual blunt brass HT fitting, of the type that goes into distributor towers, relying on a jury-rigged rubber bush in the stator plate to hold it in place. Naturally this doesn't assure a good constant contact with the coil, which explains why I could previously get it to cough a time or five after checking the spark but why it then sounded dead, which I thought was flooding or fuel starvation. On the other hand, it's amazing that it worked as well as it did for so long, off and on.
My mate has a mate in Europe who will probably be visiting SOS in the next month or two following an email asking him to buy the correct HT lead. Although this probably won't stop me trying to rig up an HT lead with a spring loaded coil contact in the meantime, if only to make sure no other parts are required.
No other improvement.
What I thought was exclusively fuel problems now looks like it might have been ignition problems as well. Despite numerous previous spark tests looking okay, I've now done some longer ones and it seems that there is an intermittent spark, or lack of spark, problem.
I've spun the flywheel with an electric drill to remagnetise it, with no improvement.
The problem seems to be due to someone not using the correct BS high tension lead. It's just a standard fibre HT lead with, at the coil end, the usual blunt brass HT fitting, of the type that goes into distributor towers, relying on a jury-rigged rubber bush in the stator plate to hold it in place. Naturally this doesn't assure a good constant contact with the coil, which explains why I could previously get it to cough a time or five after checking the spark but why it then sounded dead, which I thought was flooding or fuel starvation. On the other hand, it's amazing that it worked as well as it did for so long, off and on.
My mate has a mate in Europe who will probably be visiting SOS in the next month or two following an email asking him to buy the correct HT lead. Although this probably won't stop me trying to rig up an HT lead with a spring loaded coil contact in the meantime, if only to make sure no other parts are required.
Fixed it!
Got correct HT lead from another motor. No improvement.
For about the fifth or sixth time I checked the contact points again, and they were still open at .020". Checked the lock screw, for the first time as it was about the only thing I hadn't checked before, and found it was stripped.
I assume that the points were somehow maintaining a static gap at .020" when I tested them but presumably at higher rpm the loose lock screw allowed irregular gaps, contacts, and sparks. I put the lock screw in the other hole, which wasn't stripped, and the motor now starts and runs.
An object lesson in NOT assuming anything without checking EVERYTHING on EVERYTHING in a methodical fashion, which would have saved me a ridiculous amount of time.
I have, however, maintained my very limited reputation for fixing the unfixable, which makes me feel better for having missed the bleeding obvious.
Got correct HT lead from another motor. No improvement.
For about the fifth or sixth time I checked the contact points again, and they were still open at .020". Checked the lock screw, for the first time as it was about the only thing I hadn't checked before, and found it was stripped.
I assume that the points were somehow maintaining a static gap at .020" when I tested them but presumably at higher rpm the loose lock screw allowed irregular gaps, contacts, and sparks. I put the lock screw in the other hole, which wasn't stripped, and the motor now starts and runs.
An object lesson in NOT assuming anything without checking EVERYTHING on EVERYTHING in a methodical fashion, which would have saved me a ridiculous amount of time.
I have, however, maintained my very limited reputation for fixing the unfixable, which makes me feel better for having missed the bleeding obvious.