Search found 95 matches

by BRUCEROE
Thu Apr 22, 2010 2:02 am
Forum: Operation
Topic: Very weak spark...
Replies: 7
Views: 4505

Weak Spark

Of course you know about where cylinder #1 should show on the timing mark. The others should be delayed a known amount. A good first check, is use an inductive timing light on every plug wire, to make sure the spark happens about the right time for that cylinder. The timing mark will be illuminated ...
by BRUCEROE
Thu Apr 22, 2010 1:53 am
Forum: Installation
Topic: Is this VR signal useable?
Replies: 8
Views: 6323

Is this VR signal useable?

There are a couple problems with putting the VR beside the wheel, instead of outside it. Any side to side wobble & engine end play will directly influence the waveform, as opposed to no effect outside. It appears to me that the gaps from the side aren't as well defined magnetically, because the cont...
by BRUCEROE
Wed Apr 21, 2010 6:22 pm
Forum: Operation
Topic: Very weak spark...
Replies: 7
Views: 4505

My guess, you have a defective coil, or possibly a poor 12V power connection. Bruce Roe
by BRUCEROE
Tue Apr 13, 2010 1:05 am
Forum: Q&A
Topic: different coil output voltage in the same coil?
Replies: 2
Views: 2548

Coil pair differences

The actual coil voltage rises until the spark gap path arcs over. So the coil itself doesn't really determine it. A wider plug gap, or a fouled gap could do it. My guess is, the insulation on some of the wires is better than others. Bruce Roe
by BRUCEROE
Sun Apr 11, 2010 1:06 am
Forum: Installation
Topic: MJLJ Connector pin-out?
Replies: 1
Views: 2047

MJLJ PIN OUT

The picture MEGAJOLT LITE JR V4.X CONNECTOR PINOUT is looking at the connector from outside the case. Notice the screw heads at the corners. The pin at lower right is +12v; you could verify this by tracing it back to the + (9V battery) test point on the circuit board. Incidently that is connector pi...
by BRUCEROE
Sat Apr 10, 2010 3:11 pm
Forum: Operation
Topic: 1 year on, a problem
Replies: 5
Views: 6223

1 year on, a problem

My experience is, tin plate connections at logic levels will fail some day. My fixes are to either solder things, or use gold to gold connectors. A chip can be placed & soldered into a "carrier" with gold plated pins. That may be plugged into a connector with gold plated pins. One processor built he...
by BRUCEROE
Fri Apr 09, 2010 8:57 pm
Forum: Operation
Topic: BATTERY CURRENT FOR EDIS
Replies: 3
Views: 3191

EDIS CURRENT

Guess I should have said, this was run on the bench using my trigger wheel emulator circuit. And up to 4 coils/8 spark plugs. That makes it easy to get any coil config desired, no hot screaming engine. Bruce Roe
by BRUCEROE
Fri Apr 09, 2010 8:34 pm
Forum: Operation
Topic: BATTERY CURRENT FOR EDIS
Replies: 3
Views: 3191

EDIS CURRENT

alhbln, Thanks for the comment. My objective here was to find out how much DC current my wimp alternator must supply to keep up. This was a new load on a rather small source, 'cause the old ign ran off flywheel magnets, no battery. I put a pretty heavy filter on the input to smooth the spikes, and m...
by BRUCEROE
Thu Apr 08, 2010 4:59 am
Forum: Operation
Topic: TUNING PLAN FOR ENGINE WITH PREVIOUSLY FIXED SPARK ADVANCE
Replies: 0
Views: 2128

TUNING PLAN FOR ENGINE WITH PREVIOUSLY FIXED SPARK ADVANCE

TUNING PLAN improve mid range torque lower possible idle speed reduced fuel consumption at part throttle with more advance ease starting with reduced cranking advance MJLJ-V4 TUNING PLAN use manual ADVANCE knob to shift entire map up to + or - 12 degrees after best advance found, modify ignition map...
by BRUCEROE
Thu Apr 08, 2010 2:32 am
Forum: Operation
Topic: Could you do twin spark ?
Replies: 21
Views: 12448

PARALLELED IGN COILS

There is a very basic reason, why 2 coils can't be driven in parallel by the same driver. When the current turns off, voltage on all windings will rise ONLY until current flows through ONE pair of spark plugs (ignition + waste). At this point that circuit voltage will drop, as will voltage on ALL th...
by BRUCEROE
Wed Apr 07, 2010 5:28 am
Forum: Operation
Topic: Engine does not start
Replies: 15
Views: 7450

Degree F trans chart: Bruce

255 255 255 255 255 255 255 255 255 255 255 250 245 240 235 230 225 221 217 213 210 207 204 201 198 195 193 190 188 186 184 182 180 178 176 175 173 172 170 168 166 165 164 162 161 159 158 157 155 154 152 151 149 148 147 146 145 143 142 141 140 139 138 137 136 135 134 133 132 131 130 129 128 127 126 ...
by BRUCEROE
Tue Apr 06, 2010 2:24 am
Forum: Installation
Topic: Trigger Wheel, shrink fit vs. bolting/welding?
Replies: 5
Views: 5848

Balancer

The picture looks like the trigger wheel is on the outside of the harmonic balancer. On several of mine, the old rubber has let the outside slip, loosing the timing mark. But in this case, the engine would stop. Bruce Roe
by BRUCEROE
Sun Apr 04, 2010 7:07 pm
Forum: Operation
Topic: Engine does not start
Replies: 15
Views: 7450

Temp Readout

I sent a file to AUTOSPORTS LABS, which reverses the readout and properly scales it to read degrees F when using the very common (2 wire, EFI) coolant temp sensor. Bruce Roe
by BRUCEROE
Sun Apr 04, 2010 3:20 am
Forum: Operation
Topic: BATTERY CURRENT FOR EDIS
Replies: 3
Views: 3191

BATTERY CURRENT FOR EDIS

I ran a curve to see what the battery current would be. With an efficient electronic dwell, its pretty much proportional to number of ignition coils driven times rpm. There is a base current of around .12 amp with the engine not running, which increases to maximum of .22 amp by 1000 rpm. Each coil a...
by BRUCEROE
Fri Apr 02, 2010 3:38 am
Forum: Powered by Megajolt Gallery
Topic: KOHLER 20 HP ODD FIRE TWIN
Replies: 2
Views: 4820

KOHLER 20 HP ODD FIRE TWIN

Ok, its running & partially tuned. Already there is a big difference in performance, from the old fixed advance to an optimized spark advance. 100 hours a year running this engine, and 22 degree fixed ignition just wasn't doing it. The odd fire twin is running an MJLJ-V4 and an EDIS setup, but only ...