Cb360 Reassembly Help

If you 'dip' the carbs it will dry out the felt seals on throttle shafts. As long as you get all the water out and re-oil them it usually isn't a problem. Treks guide is probably the best one anyone can use for 360 carb DIY. it covers stuff that isn't in any manual. The only caveat, if you want to run 'pods' carbs need further work to fix the 3K~4K missfire

crazypj said:

If you 'dip' the carbs it will dry out the felt seals on throttle shafts. As long as you get all the water out and re-oil them it usually isn't a problem. Treks guide is probably the best one anyone can use for 360 carb DIY. it covers stuff that isn't in any manual. The only caveat, if you want to run 'pods' carbs need further work to fix the 3K~4K missfire

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I read Treks guide through and through haha.
You rebuilt them actually, PJ. What other work would it need?

The slide was stuck, so I took the right carb top off and set the slide back down and all functioned properly again.
I started the bike back up, and it is idling still around 3-4krpm.
I tried to adjust the idle but turning the screw doesn't effect anything. Also, adjusting he pilot screws dont seem to do anything either.

cb360j said:

You rebuilt them actually, PJ.

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Are you saying PJ built your carbs?

Turning the A/F adjusters at 3-4k rpm? You really won't see any effect.

Sounds like you may have a vacuum leak or your throttle cable is maladjusted.

Yessir he did. He and I have talked some on Honda Twins so I don't expect him to reply here lol

Looking for vaccum leak right this second.

Cna't find any vaccum leaks.

Turned the choke on just to see what happens.

Obviously, it slows the idle down a lot. Open it back up, back to high idle. the right carb is sorta blowing some misted fuel out as well

The right carb is blowing fuel mist out of where?

If PJ has had your carbs in his hands then they need nothing other than a quick once over (after bouncing around the UPS truck) and gauge sync/tuning.

You can double check the float heights and operation. PJ still sets them at 21mm as far as I know. Keep them at his 21mm.

They mist fuel out of the right carb intake side. I am going to check right side intake valve clearance. Actually, might as well check all valves

cb360j said:

They mist fuel out of the right carb intake side. I am going to check right side intake valve clearance. Actually, might as well check all valves

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MmmHmmm.

How long ago did I do them? (or better, when did I send them back end of last year or 2019?) Were they the ones with slides gummed in? If so, I washed them out pretty good but don't remember if they went through ultrasonic cleaner? So far, in about 10? years doing 350/360 carbs if there is a 'carb' problem' 99.99% of the time it's either charging, ignition or cam timing/valve adjustment. ;D

Let it be known, I fully trust PJ'S Carb abilities and fully assumed it was something I had messed up lol.

Went to adjust the valves yesterday, and found what couldv'e been a horrible thing. The exhaust valve adjustment screw and nut was missing on the right side. I was sad. Took the night to think it over, and pulled the top end off today. Thankfully, under the valve cover was the screw and nut sitting pretty. I pulled the head to check and make sure nothing was ruined anyway. Everything was still tip top. Unfortunately, the screws threads are marred up a little, and I don't have the correct die for it. So I am just going to order another from CMC. I am not sure if this was the cause of high idle or not, but, I am so thankful I found it before I started the bike again.
Thanks for the help so far everybody

It won't be cause of high idle but the noise must have been pretty horrendous noise? It does make valve timing extremely 'short' probably with pressure in cylinder when intake valve opens causing the back pressure you had pushing fuel out.? At least your in the 99.99% bracket 8) ;D If you still have it apart, check the bottom threads of rocker arm and top of valve.(use adjuster screw from different cylinder) I haven't seen it happen on a 360 but I have seen the damage on the later CB/CM400'3 valve' motors.where valve tip is small and the threads completely gone causing rocker to 'pull' valve sideways wearing valve guide.You probably caught it before it did any real damage

I had a 360 that had "ovalled" tappet screw holes. Not sure what caused them to oval, but after the second time losing the same tappet, I took a closer inspection.

The bottom of the screw still threaded into the tappet on both ends, so I think it shouldn’t be ok. , I’m glad it didn’t oval out like iris did.
And I didn’t hear it because I’m one of the people that made their exhaust to loud. It’s long enough, but to loud haha. Making me rethink how loud I need it.... then again, I’ve really only heard the engine at 4,000 rpm so it makes sense it would be loud lol. Been wearing hearing protections when it was running, probably why I didn’t hear the valve tappet (or maybe I don’t have the ear for it)

Got the adjuster replaced, and top end back together. re-timed (I am getting quick at it), and went to start up again after I adjusted valves. Ran for maybe a second or two, then died.

No backfires.
-I didn't do anything to the carbs, so I don't assume the bike is getting fuel. I should've pulled a plug just to see if it has any fuel on it.
-The timing is spot on, and it is definitely getting spark.
- I noticed that the left plug is very dark now, from running previously. I am not sure what this means, so is this indicative of say, the bike running rich when it did run?
- When the bike was running, it was idling really high. So some of you told me to check for vacuum leaks. i couldn't find any, but I took the right side intake manifold off to make sure it was seating properly on the carb. It seemed to be, so I put it back on and did my absolute best to make sure it was in the intake as best as possible. Has anyone ever had any trouble with these not seating properly?
- I noticed the carbs sag, just a little bit in the manifolds so I will have to do what Trek did and suspend them with something.

Either way, first plan of action is to check valve clearances again just to ensure I got it 100% correct.

Are the A/F mix adjusters two turns out?

It will idle rich at start up due to choke being closed.

Once warmed up w choke fully open ( adjusted for fastest idle) it still be a bit rich at idle because its an air cooled engine and a lean idle will cause over heating issues.

The richer mix allows it to run cooler.

When the bike was running with a high idle did you turn out the idle speed adjuster to slow it?

Ensure you haven't over tightened the insulators to the head as this will cause them to warp and leak.

Smear a bit of grease inside the insulators to ease carb installation.

FWIW. Adjusting valves is the only adjustment you should make w the engine cold. All other adjustment are made at operating temp.

Once running adjust idle speed, then A/F mix for fastest idle, Then re-adjust idle speed, Then sync, Then check timing w a strobe light. (Idle and advance)

The mix adjusters are two turns out.

When it was idling really high, any carb adjustment was negligent. nothing changed no matter what I did, so thats why I believed it to be a vacuum leak.

Last night I was fooling with it, just trying to get it to start. with the battery fully charged, I went to press the push start and the button didn't work. I thought that was weird, I flipped the kill switch on and off a couple times, and then the push start worked. The bike started then died again.
I took the switch assembly off the handlebars to see if I could replicate the problem, and I could. I took it apart to make sure some of the switch contacts weren't touching or burnt. Nothing seemed amiss.
I am going to check every piece of wiring tomorrow to make sure it is all ok before I definitively say the switch assembly is bad, or just try a different one.

Also, when it ran for a few seconds I felt the exhaust pipes to see if both cylinders were running, only the left pipe was warm.I looked inside the right cylinder carb, and the slide is stuck up again. Not sure why it keeps doing that. When I go to fix it, can i use some sort of lubricant to make sure it doesn't get stuck due to friction or would anything inside of it contaminate things?

It's very unusual for a slide to stick after it's been free'd off, have you removed top to make sure nothing fell in during shipping?

I’ve had to free it once already. Nothing looked like it had fallen. I will post pictures once I take it apart again.

Check inside carb bore, could be a burr from prying on it? (can't really think of anything else?) You haven't fitted washers under needles?

check vent hole orentation in the bottom of slides. They have to be nearest the filter, not engine.

If they are engine side it will cause them to hammer themselves to death and they will wedge

Its very common for the slides to actually twist themselves around even w the Honda diaphragms w locating tabs.

If they have twisted around.
hold the plastic ring and twist it very gently back to position until the locating tab on diaphragm is lined back up and holes locale is correct.