'74 360 (won't start) Spark but no reading between boot and coil

huck_finn

Been Around the Block
Doesn’t even act like it wants to start…tried to double check everything I have read before posting, need some expert advice. Here is what I have run through at this point (not sure why the coils are reading so high though).

Electrics
Right side coil - 8.1
Left-side coil - 7.9
No reading between coil and spark plug boots (new NKG boots)
Can’t get any kind of reading on condenser (bought a new one in the last six months)
Continuity on stator is just as it should be
Continuity on regulator/rectifier combo is as it should be
Get good spark on both plugs (blue, every time I kick the bike over)
Timing is dead on (new points were added in the last six months as well)
Battery has full charge (Earthx Lithium ETX12A)
New wiring harness from Sparck Moto (all other electrics are working just fine)

Mechanical
New cam chain guide and tensionor
Cam Chain tension has been set
Valve heights set to Honda specs
Carbs are bench synced, and float heights (double checked them last night) are at 19 mm (read that a higher float height would help to keep the engine from running too rich, which my plugs were showing)
Main jets are 100’s
I rebuilt them both within the last six months
Bowls have fuel in them
 
I did forget to mention that I am kick start only - and don't have the solenoid connected in the wiring harness.
 
huck_finn said:
No reading between coil and spark plug boots (new NKG boots)
Can’t get any kind of reading on condenser (bought a new one in the last six months)
Get good spark on both plugs (blue, every time I kick the bike over)
Just want to make sure- You're saying you are definitely getting good spark, correct? If you kick the bike over and you have good spark on both plugs, then your issue is probably elsewhere like fuel. You have good compression, right?
 
Not sure why I wasn't getting a reading before - but I was just able to get a reading on my spark boots:

Right: 9.8K
Left: 9.23K

Are these numbers too low? If so - would they prevent the bike from turning over?

Just for the hell of it I kicked it over a few times - got a freaking loud backfire on my right side exhaust and noticed an odd smell. It was kind of fishy - it was only coming out of the right side exhaust. The left side smelled like fuel.
 
irk miller said:
Just want to make sure- You're saying you are definitely getting good spark, correct? If you kick the bike over and you have good spark on both plugs, then your issue is probably elsewhere like fuel. You have good compression, right?

Spark appears to be good - blue from both plugs when out of the engine. I don't have a way to test my compression - but will see if I can pick up something this week.
 
huck_finn said:
Right: 9.8K
Left: 9.23K
These are right around where they should be. You're supposed to test with the boots off, so the numbers are inaccurate a few hundred ohms. As long as they aren't more than 11k or so.
 
irk miller said:
These are right around where they should be. You're supposed to test with the boots off, so the numbers are inaccurate a few hundred ohms. As long as they aren't more than 11k or so.

Then it sounds like my electrics are running within a normal range. Is there anything else that you could think of that might be causing me headaches (from an electrical standpoint?
 
Double check and make sure your timing isn't 180 out. It's not hard to do. If you're getting a backfire, then it's igniting fuel in your exhaust, so you know something is getting in there. Also, double check that you're setting valves at TDC. You can pull a plug and test with a pencil in the hole to make sure.
 
irk miller said:
These are right around where they should be. You're supposed to test with the boots off, so the numbers are inaccurate a few hundred ohms. As long as they aren't more than 11k or so.

Just so I know I am doing it right...when I checked my timing, I pulled my left spark plug - and rotated the engine until I could feel suction with my thumb. If that sounds about right, then I am more than happy to check my timing again tonight.

I will also double check my valve heights again - I used a video from Common-Motor as a guide (https://youtu.be/xlx9xu22mLM)
 
Timing is done at TDC, which is compression. At the the top of the stroke where it pushes your finger out. It sucks on the way down.
 
irk miller said:
Timing is done at TDC, which is compression. At the the top of the stroke where it pushes your finger out. It sucks on the way down.

Then I must have it done completely opposite. Hopefully I can get it corrected tonight.
 
It's easier to rotate the motor with the plugs out, so pull the plugs, then turn the motor to the TDC on the stator. You can test for the piston at the top of the stroke with a pencil through the plug hole. It shouldn't go very far into the hole on the side you're setting the valves on. Repeat for the other side. Same goes for timing.
 
Height and timing set - spent about 20 minutes setting the timing on the right point alone - wanted to make sure it came on just when it was supposed to. Same issue - I get a pretty good backfire out of the right exhaust, and dirty looks from my wife because the kids are already asleep.

Anybody see something that I am missing?

Otherwise I am planning on pulling my carbs, breaking them down, and tossing everything into a bucket of carb cleaner for a day. I cleaned them pretty well - but there could be something I missed.
 
Finally found my culprit - the spark advance was not seated onto the post on the cam... freaking idiot.
 
huck_finn said:
Finally found my culprit - the spark advance was not seated onto the post on the cam... freaking idiot.
You'd be surprised by how common that is. Don't beat yourself up over that one.
 
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