505 1/d No Spark

Hello, I've got a 1980 Sachs Hercules Suburban with a 505 1/d engine and I can't get it to run and have found that I wasn't getting any spark. Using a test light, I found that, while pedaling, I was getting power to the coil, but no power to the plug. I took the coil off and tested it using a multimeter. I ended up getting 2.2 ohms from the positive and negative and 6k ohms from the positive and spark plugs and wires. As far as I can tell this means the coil is fine. Is there something else that could be going on here? I'm in the process of trying to get the points cover off so I can look at, adjust, and clean them, but I don't know if that could even be the problem when I'm getting power to the coil. Thank you for you time.

Re: 505 1/d No Spark

Richard Eberline /

Isolate kill switch,

in the taillight is a ohm resister.

The wires of the 6.5 ohm resister are soddard on. The bulb has to work.

You can bypass this safety device.

Re: 505 1/d No Spark

There's a blue/black wire outta the stator, ground it.

It runs the brake lights and acts as the ground for the ignition stator coil. It's what Richard was alluding to above - essentially it runs the brake light off the same coil as the ignition, if the brake light's blown or any part of the brake wiring is not wired correctly, no spark. This is best to bypass, and really easy - just ground that blue/black wire.

if that's not it, clean and set the points. and maybe replace or wire an inline condenser. The coil doesn't just need power, it needs pulsed power that breaks when the points open and forces the coil to throw the spark at that exact timing. if the points are shorted or something else not working condenser etc you can get power to the coil but not little spark-worthy pulses

Re: 505 1/d No Spark

Ok, so I did a lot of what you guys said, but it turns out that my taillight and brake light work fine and even after bypassing it, it still wasn't firing. I ended up finally getting the pints cover off and found that the points were in a position where they weren't even touching the low points on the camshaft so they were just staying closed. I was able to fix this, but I'm at a lose for how to actually set the gap. I've got the engine at top dead center, but the only screw that looks like it would adjust the point gap is the flathead one, but that moves the entire points plate.

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Re: 505 1/d No Spark

Actually, I think I got it figured out, it is that flathead screw. I got my points gap right and the points open and close now, but I'd like to clean up the rust and stuff on the crankshaft a bit and get some grease on the brush. Any ideas on what would be safe to use here and how I could do it? Thank you.

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Re: 505 1/d No Spark

The moped runs and rides great :)

Re: 505 1/d No Spark

With the points cam like that^ , it won't run good for very long .

Pull the flywheel and clean that crap out . Make sure the cam is smooth and the oil wick is lubed .

Re: 505 1/d No Spark

I was afraid I might have to pull the flywheel to get to clean that up. Thanks for the advice. I wonder how it got like that in there, the bike has 800 miles and is practically spotless on the outside.

Re: 505 1/d No Spark

Doesnt take much, I've seen stuff rust overnight after one rainstorm

Re: 505 1/d No Spark

well if u dont have the puller, u might clean with sandpaper taped on a screwdriver, steel wool on a stick, paper towels wadded etc... blast compressed air, n brake cleaner to wash down. then u can oil theat felt pad from the slots too. saves the anguish of waiting for a puller.

Re: 505 1/d No Spark

holy crap!

flywheel puller on a sachs is needlessly annoying, the angle spark plug means you can't use a regular piston stop (you can, but don't. definitely don't) and the overlapping lip around the flywheel means you can't use a strap wrench either.

While not ideal, I usually jam a screwdriver through the flywheel windows and brace it against the case to keep the crank from spinning while tightening/loosening the flywheel crank nut. you have to be VERY careful though that your screwdriver isn't braced against the stator plate or coils or you absolutely will ruing the coils and or stator.

Better is, if you have one, use an impact driver or get a flywheel holder tool. Or perhaps a better idea than the driver through the flywheel, or at least a little more foolproof - stick a piece of rope or cutoff bit of bungee cord in the plug hole to act as a piston stop. you gotta be careful there too that when you put it in you have enough in there to stop the piston, but you don't want the rope to go out into the transfer or exhaust ports at all.

ANYWAY definitely get a puller and definitely clean that cam lobe, the little feeler that opens/closes the points rides on it. rusty gunky surface makes spark erratic and weaker and it will get worn away quickly and you'll loose spark

Re: 505 1/d No Spark

holy crap!

flywheel puller on a sachs is needlessly annoying, the angle spark plug means you can't use a regular piston stop (you can, but don't. definitely don't) and the overlapping lip around the flywheel means you can't use a strap wrench either.

While not ideal, I usually jam a screwdriver through the flywheel windows and brace it against the case to keep the crank from spinning while tightening/loosening the flywheel crank nut. you have to be VERY careful though that your screwdriver isn't braced against the stator plate or coils or you absolutely will ruing the coils and or stator.

Better is, if you have one, use an impact driver or get a flywheel holder tool. Or perhaps a better idea than the driver through the flywheel, or at least a little more foolproof - stick a piece of rope or cutoff bit of bungee cord in the plug hole to act as a piston stop. you gotta be careful there too that when you put it in you have enough in there to stop the piston, but you don't want the rope to go out into the transfer or exhaust ports at all...

ANYWAY definitely get a puller and definitely clean that cam lobe, the little feeler that opens/closes the points rides on it. rusty gunky surface makes spark erratic and weaker and it will get worn away quickly and you'll loose spark

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