Left the gas on

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Once you got everything dried of gas and refilled (leave the primary dry) you could start it up for a little bit and see if you are getting oil in the primary. Shouldn't hurt anything.

Anyone disagree? Obviously not ride the bike like that.

Yes, He could do that too. The old saying, "patience is a virtue" applys here. Resist throwing it back together to get from A to Z just so you can glimpse the pot of gold at the end of the rainbow.

Carburator first!


"Disassemble, Diagnose, Repair, Rebuild, Ride it with confidence"
 
Yup, Carb first. Get it right. Then deal with primary. Order up a clutch tool, you will need it eventually.
 
Has anyone mentioned oiling the bores yet?

All that petrol got into your engine by going past the pistons and rings, washing away the oil in the process, you now have very clean, and dry, pistons, rings and bores.

Squirt some oil in through the plug holes, turn the engine over gently a few times (turn it over fast and you’ll just dump the oil in the exhaust) and leave it to soak past the rings.
 
It’s worth looking at the plug color to see if it’s been flooding on the move as well.
 
Has anyone mentioned oiling the bores yet?

All that petrol got into your engine by going past the pistons and rings, washing away the oil in the process, you now have very clean, and dry, pistons, rings and bores.

Squirt some oil in through the plug holes, turn the engine over gently a few times (turn it over fast and you’ll just dump the oil in the exhaust) and leave it to soak past the rings.

FWIW, one of the techniques used nowadays by some engine builders is to install pistons/rings 'dry' so if that wasn't done when the engine was last rebuilt, here is the opportunity to try that procedure! ;)
 
Yeah well, having experienced the effects of suspected petrol wash, I’ll leave that to others to experiment with !
 
Hey all, yes, I went for the carb first. I removed the overflow screw, and there was no leaking from there with the fuel turned back on. I pulled the float bowl and the needle and seat seem to be functioning as they should, with fuel flow stopping when I push the float arm up. The bowl seemed like it wasn't quite pressed against the rest of the carb properly, which might have been the issue or a contributing factor. The floats seemed to be floating, though I didn't read that comment until after the first carb session, so I didn't pay a whole lot of attention to the possibility that they might be full of fuel the first time I went through the carb.

Next I changed the filter, added fresh oil, put a little oil under the exhaust valve covers and into the cylinders. Kicked her over a bunch of times with the plugs out to get the oil spread around a bit, and tried starting her. That turned out to be a real challenge, she would almost fire a bit but not quite run with some early kicks. Pulled the carb and cleaned out the jets, and this time I checked to see if the floats were full of fuel - confirmed they are not.

The tab that engages the needle and seat was bent up quite high though, to cut fuel off early, and the bowl was only about half full when I opened it. I figured that might be the cause of my hard starting troubles, so I bent that down a little to allow more fuel into the bowl. Put it all back together and still no fuel coming out of the overflow with the gas turned on. Tried starting again, and same thing. Could get her to run for very brief stints of maybe 20 seconds at most before she would cut out. Sometimes on two cylinders sometimes on one. Discovered that I was getting good spark on one side, and not on the other. Turned out to be the plug. Changed that and got both sides firing. Still having trouble getting her going.

The good news is that there doesn't seem to be any oil showing up in the primary. Between the very brief periods when she ran for a few seconds, and the seven million kicks to make that happen, I'm sure if there was a leak at the crank seal there would be evidence by now. The bad news is the starting issue. She was starting first or second kick every time before this.... I'm beat to a snot from kick start attempts... Do you think this is carb related, or is this something more sinister?
 
It's pretty easy to get one of these flooded if they don't start on the first two or three kicks. Next time if it doesn't start after 3 kicks, take the choke off and open the throttle about 3/4 and give it a couple of trys.
 
I don’t think you can just randomly set the float height and expect it to run.

Too be honest I find Amals challenging enough. I’d never take on those fancy carbs.
 
Yes, I could be flooding it. Seems sort of like I'm flooding one cylinder, and not getting enough fuel in the other one. I'll give the 3/4 throttle trick a whirl tomorrow.

And I hear you on random float height settings. The last setting was my own and where I've got it now looks a bit more in line with the setting in the manual for the carb. Based on eyeballing it. I could get all scientific and measure it tomorrow to be totally consistent with what's in the manual, and I'll probably have to take it off and apart at least a couple of times tomorrow anyway...
 
Carbs ARE an exact science, so yes, get all scientific! Luckily you have only got one.
 
My bike has similar setup single Mikuni carb , Boyer mk4 EI .... starting procedure is , turn fuel tap on, flip enricher lever on top of carb , kick engine over once or twice , flip enricher off , turn ingnition on , kick engine over while being ready to twist throttle when it fires .... almost always starts
 
My bike has similar setup single Mikuni carb , Boyer mk4 EI .... starting procedure is , turn fuel tap on, flip enricher lever on top of carb , kick engine over once or twice , flip enricher off , turn ingnition on , kick engine over while being ready to twist throttle when it fires .... almost always starts



Same here, the Mik enrichener feeds a lot of gas. From cold, just a kick or two then turn it enrichener off to start. When hot it doesn't need enrichener at all: First kick every time.
Jaydee
 
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Sounds like a classic case of clogged / improper pilot jet.
However I would do a complete assessment.
I would.

1. Verify battery charge.
2. Verify all E connections, loose wires / connections?
3. Strong Blue spark on both plugs.
4. Verify both fuel taps are flowing and not clogged.
5. Set correct float height.
6. Replace / clean pilot jet.
7. Confirm main jet is tight.
8. Confirm enrichener / choke is working properly.
9. Disassemble air screw assembly, clean, verify condition, set at 1 1/2 turns.
10. Turn idle up a little.
11. Turn on both fuel taps for initial fill.
12. Starts by third kick.
 
Has anyone mentioned oiling the bores yet?

All that petrol got into your engine by going past the pistons and rings, washing away the oil in the process, you now have very clean, and dry, pistons, rings and bores.

Squirt some oil in through the plug holes, turn the engine over gently a few times (turn it over fast and you’ll just dump the oil in the exhaust) and leave it to soak past the rings.
I was gonna mention that, then oldtimers disease kicked in.
 
Looks like I've got a day off of work due to a water shut off :)!

Tried to start a couple of times as is before getting into the next carb removal and disassembly adventure. I've noticed that I'm consistently getting good spark on only one plug. I only have 4, and I've been trying to get away with cleaning them and switching them back and forth, but it looks like that's no longer gonna cut it. Three of the 4 seem to be toast. I imagine that this has to be a pretty significant factor here. I went through all of the ignition wiring the day before yesterday and it's all good. The one good plug is producing a nice strong spark on either side, while the others either don't fire at all or just a faint intermittent spark - again, same on either side.

Thanks for the list Craig and MichaelB. I'll check the local stores and see if they have any plugs first, and will get some if they do. Otherwise I'll have to order some in and wait for them to arrive. When I get good spark on both sides I'll try it, and if it behaves the same way I'll go through the carb again. Hopefully there are suitable plugs here in town!!
 
Aaaarrrrggg... No suitable spark plugs in town... Looks like I've got to place an order and start waiting. Such a beautiful day too!!!
 
I've never ran into a plug I couldn't clean a spark out of. Something else is up if you are consistently killing plugs.
 
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