CL360 refusing to start

Hey guys,

I was working on getting my 1975 cl360 started over the weekend and I seem to be having issues.

Here is a list of what I have checked out/done so far:
1) All wiring for it to turn on and run confirmed working.
2) Cleaned carbs before putting the bike back together and I put the fuel tank back on and gassed it up with about a half tank. I confirmed that gas was indeed moving through the petcock and into the carb fuel lines but I am not sure how to check if gas is moving into the carbs while it is on the bike, any help with that.
3) Starter turns the motor over.
4) Coils hooked up and with the spark plugs are sparking when pressing the starter button and holding them against the engine head.
5) New spark plugs
6) Sprayed starter fluid into the carbs, and I get one or two loud backfires
7) Put a little gas (1/8 oz) directly into the cylinder and I get the same thing, it will backfire once and then nothing.
6) Pulled the stator cover and the points cover. Points seem to be working correctly but could use a little adjustment (would I be getting any spark if the points were way off?) I have not played around with the timing yet but that is next on my list.

I just wanted to see if there is anything else I could be missing. It seems like everything is in working order but I cannot get it start. I know there are probably a hundred of these threads and I have read through many of them with no luck so far, any help would be appreciated.

Thanks,
Chris

I'm gonna recommend you check you have a healthy battery.

I guess I should have mentioned that. Battery is brand new as well. I thought that could be the issue as well so I hooked the battery up to a charger and put it on engine start and that didn't do anything either.

Here is something I just thought of, the two black wires with the white strip to connect under the tank. Does it matter how they are plugged in? Could I possible have them connected in the opposite port?

Okay youre getting spark which is a good first step.
Next step is to cool your jets and get the bike set up properly to run before attempting to run it

You need to sit down and set your timing. Just because the points "work" doesn't mean your timing is right, and if its backfiring consistently I would assume your timing is way off. Its an easy procedure and is in your manual, also on here and hondatwins if you search.

Secondly you need to set the valve clearances. They need to be dead nuts on.

To check if you're getting gas to the carbs theres a few ways. First pull a plug after cranking for a second, is it wet?
Also loosen the drain plug in the bottom of the float bowl on the carb. Does gas come out?

Check your compressions, is it equal across both cylinders? Is it over 120 PSI?

Once you do all of that the bike should start right up.


The two black wires with white stripes come from the kill switch if my memory serves, and are both just constant 12V hot, so doesnt matter if you swap them.

Thanks Sonic,

That is exactly what I plan on doing next. I just ran out of time yesterday while working on it and the bike is sitting in a garage that I will not be able to get to until the end of the week so I thought I would try to do some troubleshooting and research before getting back to it. I have the manual and I plan on running it through a timing tune next weekend.

I will look into setting the valve clearances as well. I checked the compression yesterday and I was getting right about 145 psi on both cylinders.

Thanks for helping me out, looks like a have a list of to do's for the weekend. Hopefully after I go through your list I am able to get it running.

Ignition timing is my suggestion, too, but I'll go one further. Try swapping the blue and the yellow wires where the lead from the points to the ignition coils. Getting the advancer out by 180° during reassembly is a common mistake.

Thanks for the advice Sonreir, I will try swapping those wires as well as tuning the ignition timing this coming weekend. Hopefully that will do it.

I got to do some more work on the bike today and after doing the timing tune and getting that working correctly I tried to start it up again and nothing. I think I have it figured out now though. I tried to drain some fuel from the bottom of the carb float bowls and the right carb is good but nothing came out of the left carb which leads me to believe that the float is stuck. Unfortunately I didn't have enough time today to take it apart again but I hope I can get to it on Friday. I poured a little gas directly into the spark plug holes and got it it fire a few times but even with one carb working shouldn't it technically fire up? I just want to make sure I have all of the bases covered. Regardless the carbs are coming off again and cleaned (again) to see if that fixes the issue. Thanks for the help guys.

I wouldn't mess with the carbs until after you verify compression and timing.

I double checked the compression yesterday and followed the steps to do the timing as well so I think they are good. I am not sure what else I can do to check them.

Obviously no gas leaking out of the bottom of the one float bowl when the drain is loosened, right?

Has this bike ever been running since you've had it? Was the points assembly ever removed and reassembled? Sounds like it could be 180* out, you'll still get spark but on the wrong stroke.

If it was running before, what has changed since?

The bike was running when I bought it back in November. The points were never removed since I bought it so that doesn't seem like it could be the issue.

It was running fine when I got it so really nothing with the engine changed. That is what I was thing to think about. I had everything stripped down. Took the carbs off and cleaned them, after that they sat in a box for about 3 months. The floats were working at that time.

santogd182 said:

I double checked the compression yesterday and followed the steps to do the timing as well so I think they are good. I am not sure what else I can do to check them.

Obviously no gas leaking out of the bottom of the one float bowl when the drain is loosened, right?

Click to expand...

Do the timing with a strobe light, not with the directions in a manual. Manual is good for "close enough" but doesn't do much when it comes to troubleshooting or diagnosing problems.

Thanks Sonreir, I will look at picking up a strobe light this week and checking the timing again.

Even a cheapo from Harbor Freight should be able to help out.

Sonreir said:

Do the timing with a strobe light, not with the directions in a manual. Manual is good for "close enough" but doesn't do much when it comes to troubleshooting or diagnosing problems.

Click to expand...

Gonna be tough without a running bike ;D
I suppose you could keep it spinning with the starter.
Every time I set timing statically I'm within 1 degree or so once its running and I hit it with the timing light.


https://www.youtube.com/watch?v=HQUBA3wZwCQ

https://www.youtube.com/watch?v=zSSVCx8QREk

SONIC. said:

I suppose you could keep it spinning with the starter.

Click to expand...

Exactly.

Alright, thanks guys. That is exactly what I will do. Those videos were helpful and I will see if I can find a decent light at harbor freight. Hopefully is works this time.

The timing light makes everything so much easier. It's also awesome watching it move as you slowly pry the points (CAREFULLY!!)

Alright, I got the carb float issue fixed and I am now getting gas to both carbs. Next step is to start looking into the timing again using the strobe light I just purchased.

My question is. When the strobe light is hooked up to the left spark plug wire I should be seeing the 'LF' lining up with the tick mark, correct? I guess I should also be seeing the opposite for the other side, so the right spark plug wire should be showing 'F' lined up with the tick mark when cranking the starter.

Thanks for your help guys.