The Original Sin
May 3, 2017
It can if you float needles don't hold.....which they're supposed to.
What position do you run in?
In the "on" position.
Also I've found if you have dry rot or cracks in the intake carb to motor boots that fuel can seep from them.
Ok so hear I am many weeks on this mechanical roller coaster. I've had my share of wins. I fixed my new gas tank by brazing it with silver soder . I fixed the leak in my carbs by rebuilding with new everything. I synced my carbs and just before congratulating mysef and a job so wonderfully well done I took the bike on a little test ride. OMG! What have I done!!?? It runs like crap. No problem starting and holding idle. The engine revs strong wth good response but as soon as I take it on the road the engine bogs, stutters, jerks, speeds up then lags. The bike can only run with the pet cock in PRI. Where do I start? Could it be the air fuel jets? I set them all to 2 1/2 turns out but that's now how I found them after I drilled out the factory installed caps. Can you guys give me your top ten things you'd check if you were me. Please help if you can.
Did you inspect all 4 vacuum diaphragms for tears/holes. Also the air cut off valves did you replace the O-rings in them.
Vaccum leak or pinched hose probably cause the petcock doesn't need vaccum to open up on prime. Double check your hoses.
Did you check to see if the vent tube on the fuel tank is not restricted. Also make sure your fuel taps diaphragm holes are lined up & are positioned at the bottom. Also check that the 4 mm O-ring is on all the way.
I did inspect the slide diaphragms and they seemed to be in good working condition. I sure could use some help. Can
What about the fuel tap diaphragm. When you get a new one it's already together meaning the gray plastic part is in between the 2 part rubber. All 3 pieces have a very small hole in them & they are all to line up. The hole alignment section goes towards the bottom of the fuel tap when assembled.
Yes indeed R.J. Bottom line is the carbs are coming back off! My gut tells me I probably missed something during reassembly.
People will be coming to you for expert advice after all of this! I know the frustration, spraying starting fluid around the carbs vaccum system is an old trick to check for leaks, the idol will change if it is leaking.
I really didn't expect so many problems when I bought the bike but then again it's 30 years old. Great idea spraying starter fluid. I'll do that for sure once I get these things pulled off, torn down and put back together.
Thanks for you help.
Yea, i found out (the hard way) that the clamps for the carbs to the engine need to be 100% fully screwed in or they will leak some air. Spraying starter fluid helped me determine that one of the clamps was still a few turns out. I have also pinched the vacuum line to the petcock quite a few times which starved the engine of fuel and caused instability too.
That tip is incredibly helpful.
I had to pull the carbs off Ron A. ZL 10 again. They had one plugged pilot jet & 2 stuck floats. Also I set the air mixtures screws at 3 1/2 turns out. I called my friend Ron A. the retired KAW Tech & he said to set them at 3 1/2 turns out for the starting point. What lead me to pulling the carbs is I measured the fuel in each float bowl #2 & 3 had about half the fuel in them as compared to #1 & 4. I recheck for 17 mm float height. One other thing if you spray starting fluid around the vacuum lines it is very possible to ignite a fire. I use a lawn mower fuel tank as a test tank when ever doing trouble-shooting. I hang it from my garage ceiling at about the same height that the bikes fuel tank would be. If you do this you can wrap the coils in some sort of plastic such as zip lock baggies because spark can be present even with the 4 wire leads connected.
A very special shout out and a very humble and greatful thank you to R.J and the rest of you guys that took the time to help me get my bike up and running again. I am very please and proud to inform you all that my ZL1 is running like a champ! No leaks and the carbs are all operating normally. My problem(s) after re-assembly were two fold. First, I reassembled the slide jet pins and diaphragms incorrectly, secondly I had a gap in the carb boot on the number 4 carb. Once I corrected these mistakes I cranked her up and everything is running great. Again thanks to all who talked me through my little crisis.