Engine cranks but will not start!

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Is that 10 volts while cranking or just when the switch is in the run position?

Thats 10-11 volts in the run position, when i crank it it gets around 7 volts

 

[Don S]

Re: Engine cranks but will not start!

That's not enough voltage to make the system work, no wonder you have no spark.

You need to check connections on everything from the ignition switch back to the coil. On the engine, you can check the purple wire on the shift interrupt switch, the alternator, the automatic choke. Oh, and BTW, disconnect the purple wire from the choke for during testing, you don't need the current draw changing meter readings.

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

That's not enough voltage to make the system work, no wonder you have no spark.

You need to check connections on everything from the ignition switch back to the coil. On the engine, you can check the purple wire on the shift interrupt switch, the alternator, the automatic choke. Oh, and BTW, disconnect the purple wire from the choke for during testing, you don't need the current draw changing meter readings.

I rechecked the voltage of the coil, the shift interupter purple, and alternator purple (exciter) and they're all in the high 11, low 12 range. The choke did throw off the readings a little. I'm going to keep checking.

 

[Don S]

Re: Engine cranks but will not start!

Try this just to make sure we are headed in the right direction. Get a jumper wire and go from the battery pos terminal to the purple wire you took off the choke. See what the voltages do, and see if it will start. Have water on it in case it starts, because you will have to remove the jumper to shut it off.

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Try this just to make sure we are headed in the right direction. Get a jumper wire and go from the battery pos terminal to the purple wire you took off the choke. See what the voltages do, and see if it will start. Have water on it in case it starts, because you will have to remove the jumper to shut it off.

Voltages are testing out the same as when the purp. choke cable is unplugged. I tried turning it over again but it will not start.

 

[Don S]

Re: Engine cranks but will not start!

Was the voltage to the coil still real low with the choke unhooked?

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Update: I unplugged the 3 in connector on the right side of the Ignition control module and got spark! What does this mean??

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

service manual says replace magnetic shaft assembly! I hope this works!

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Was the voltage to the coil still real low with the choke unhooked?

The voltage picked up a little with the choke cable unplugged..

 

[Don S]

Re: Engine cranks but will not start!

Plug it back in, and disconnect the shift interrupt switch and see if you still have spark.

 

[Don S]

Re: Engine cranks but will not start!

service manual says replace magnetic shaft assembly! I hope this works!

Will you please stop wanting to buy parts? You would have already bought a module for no reason, now you want to buy a part I have never seen go bad.

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Plug it back in, and disconnect the shift interrupt switch and see if you still have spark.

ok, now its changed a bit. When the shift interrupt switch is bypassed and the control module is plugged in i'm getting spark, but when i bypass the shift interrupt switch (plugging the two cables into eachother), it doesn't spark... weird. Now regardless if i have the shift interrupt plugged in or not, when i unplug the control module switch i get spark regardless.

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Will you please stop wanting to buy parts? You would have already bought a module for no reason, now you want to buy a part I have never seen go bad.

sorry I'm going to hook it up now and see if it cranks.

 

[Don S]

Re: Engine cranks but will not start!

Before you order any parts, and I don't know what manual you have, follow the chart below to make sure you know what is causing your problem.

 

[NetDoc]

Re: Engine cranks but will not start!

Go Don! Good job in walking him through this!

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

Before you order any parts, and I don't know what manual you have, follow the chart below to make sure you know what is causing your problem.

Thanks Don! I started cranking it with water attached and it would not start. I know it has spark but it appears yellow, I'm guessing this is a weak spark seeing a good one appears blue, right. i did remove the distributor cap and clean it. Do you think i bumped something out of alignment or timing?

 

[Don S]

Re: Engine cranks but will not start!

I still think you have a voltage problem. You had 10 volts at the coil earlier in this thread. You have changed things, disconneced things, and are now getting weak spark. Rather it's loose, corroded, or whatever, you had low voltage and did nothing to fix it.
Put everything back together and see what your voltage is at the coil. Leave the choke wire disconnected.
PS: Do you know how to do a voltage drop test?

 

[NetDoc]

Re: Engine cranks but will not start!

Thanks Don! I started cranking it with water attached and it would not start. I know it has spark but it appears yellow, I'm guessing this is a weak spark seeing a good one appears blue, right. i did remove the distributor cap and clean it. Do you think i bumped something out of alignment or timing?

Great: you finally got spark. Depending on how you tried to start the beast, you may have fouled the plugs. Pull one, inspect it and clean them if necessary. If they are excessively wet, remove ALL the plugs and crank the engine for a few seconds to clear out any raw gas. You might even try a bit of ether: BUT DON'T OVERDO IT! The coil will give just the spark you need to jump a gap and no more. The spark will appear to be different colors under different light and/or different gaps. The darker the ambient light, the bluer it looks.

Don may be able to tell us if your system has a ballast resistor or not. That could account for the lower than normal voltage at the coil. If it doesn't, I would be paying a lot of attention to your grounds. Often overlooked and a floating ground can cause a myriad of weird issues.

 

[EcToCrUsHeR]

Re: Engine cranks but will not start!

I still think you have a voltage problem. You had 10 volts at the coil earlier in this thread. You have changed things, disconneced things, and are now getting weak spark. Rather it's loose, corroded, or whatever, you had low voltage and did nothing to fix it.
Put everything back together and see what your voltage is at the coil. Leave the choke wire disconnected.
PS: Do you know how to do a voltage drop test?

I remember reading about a voltage drop test, so i'll re-visit that and try to perform one. As for the voltage, are you refering to the voltage with the key "ON", or while cranking?

 

[Don S]

Re: Engine cranks but will not start!

As for the voltage, are you refering to the voltage with the key "ON", or while cranking?

Both. First test the battery voltage. That is base, without that, the other measurements mean nothing.

Then check when the key is in run position, after that do the cranking voltage test on the purple coil wire.