Try grabbing it on the outside with a good pair of small channel locks. It very likely will break free.
It’s a standard metric thread, so you could probably replace it with a normal screw.
It’s in such a tight spot there’s no grabbing this, even my needle nose can hardly grab it. However, instead of spending $70ish on a dremel I figured I’d just take a cheap screwdriver and see if I could chisel a slot on it. All the hammering eventually broke it free. The bowl has a minor amount of debris in it, I’m going to clean the jets and call it a night. If all goes well, putting it back together really shouldn’t take too long.
And yes, I’m going to get new screws, they don’t look like anything special. In fact, I was thinking of putting allen screws in there and then getting a long allen wrench of the same size.
cut a slot in it with a hacksaw and use a straight edge screw driver. I use a dremel with a cutting disk but if you don’t have one I’ve done it with a hack saw.
The bowl is off. One of the jets is out, the other one is stuck, I have some WD-40 (I know, but it’s all I have here) soaking into the threads and I’ll try it again tomorrow. The jet is countersunk, so if I strip that, all I can do is drill it out and buy a new one.
You might try carb cleaner on the jet if it’s still stuck. I also had a screwdriver that I ground down to the inside diameter of the riser that helped get idle jets out (The screwdrivers that were small enough to reach were too thin and didn’t seat well.) You might also give the screwdriver a little tap on the end of the handle to seat it into the slot and to break the jet free.
That other jet soaked for two days in WD-40, nothing (as I expected). Then I found some Tri-Flow and let it soak in that for a while, nothing. I wasn’t concerned since I knew I had to run up to Lowes to pick up some new screws so I was going to grab some PB Blaster. The PB Blaster broke it free in 2 minutes.
So, both jets out, they didn’t look that dirty. The larger one (main jet?) I could see through. I poked it out with a piece of wire (straight through and all the little holes around it) and sprayed it with carb cleaner. The smaller (pilot), I did the same thing. It was more difficult to get the wire through and I never could see straight through it, but that may have just been because the hole is smaller.
It’s reassembled now and I’ll get it back on the bike soon unless I feel the need to take more of it apart, but I don’t think that’s necessary at this point.
We await your report. Too bad you can’t get at the jets without removing the carb. On my Vespas with Dellorto carbs the jets are easy to get at. I’m confident that with a clean carb and new fuel this bike will run fine. oh and put new plugs in too.
Carb is back on the bike, I just dumped the fuel and pulled the petcock. I just stepped back in to figure out how to get the filter out of the tank (without wrecking it). Looks like I just have to get a grip on and pull it out. I also noticed that the filter is missing from the carb. I’m not sure how necessary it is though.
Also, I’m still not sure if I should try firing it up before I put new plugs in to see what happens or replace them first and risk fouling brand new ones.
I would clean and re-gap the old plugs first but that could just be me.
I pulled out the old plugs, cleaned them with a wire brush* and gapped them. I poured a little bit of fresh gas into the fuel line and it fired up just like it did in the OP, that is, it just popped a few times and died. Even with some starting fluid I didn’t get anywhere.
I went through the troubleshooting in the service manual. The throttle position sensor (and wires back to the ignition control module) seem to be okay. The plugs were just cleaned, but the next logical step is to put in the new ones. It also suggests a leaking or misadjusted carb or choke, but I’m guessing that’s not it only because it ran perfectly the last time I rode it.
There are two filters on the vacuum line (where it draws air in from atmosphere). I want to disconnect those and see if it makes any difference. Also, I should check to see if I can pull the choke off without taking the carb off again. Looking at the service manual, it looks like it’s easy to make sure it’s adjusted properly.
After that, it seems things get more engine-y and less likely to be the problem. ie Compression issues (valve stuck open), timing issues etc.
Its not a valve stuck open - you are not going to get the engine to even turn over on such an engine.
Have you determined if it has a vacuum operated fuel shut off, because the diaphragms can harden or perish.
It does have a vacuum shutoff (as opposed to a fuel pump), yes. However, last night I still had the tank off and poured gas directly into the the fuel line. After I was done, I opened the carb drain and the remaining fuel poured right back out, so I know it was getting in there. Also, before I started it, I turned the throttle a few times and the accelerator pump squirted some gas into the carb.
As for the valve being stuck open, that was just one of the troubleshooting things the service manual mentioned for hard starting.
It still sounds like s fuelling issue, you have spark and you have rotation, I guess you could check compression just in case.
It could not be something really dumb like a mouse nest clogging the exhaust now could it?
:smack:I still keep forgetting to check that. I’m going to be really annoyed if that the case. Especially since every winter I stuff some plastic bags up there for just that reason. Not that it was sitting over winter, but it’s not like it’s something I haven’t thought of. I’ll have to remember to look at that when I get home. I also went to take a closer look at some of the vacuum lines, including disconnecting those filters. Long shot, but I can try it.
ETA, I’ll probably also swap out the plugs at some point and take a better look at some of the electrical. Also, I may run the battery up to Autozone or Batteries Plus and have them check it. It’s entirely possible, now that I think about it, that it just doesn’t have enough juice to to really get the starter going. Even if it was okay before, it’s been cycled an awful lot over the past few weeks (but if it wasn’t the battery before, it’s probably not now, since it’s acting the same).
Checked they exhaust pipes nothing has been living in there. I never did get around to the vacuum lines, instead I started investing the spark. I grabbed a spark tester for a few dollars and checked the coils.
Before I did that, I checked the coils themselves. They’re getting 12v on the primary side. The resistance on one is 2ohms and the other is 4 (That seemed odd). I couldn’t get any reading from primary to secondary.
Now, that all took me about 20 or 30 minutes. When I was done, I plugged the spark tester in (in line) and tried to crank the engine and the battery was dead. I let it charge all the way back up to 13v (didn’t test it beforehand) and I pulled the negative cable off. I’m curious as to if it runs itself back down overnight without any draw on it whatsoever. If it’s down, I’ll get a new one, but either way, I think I’ll run it in and have it tested.
Uh Oh - you had not checked out the battery, if your bike is one with constant headlights then a weakfish battery may not recover from the start pulse fast enough to maintain running - battery is a totally good bet
It was still at 12v this morning, but I only got three cranks out of it and it was done, just clicking after that. This is the first time it’s clicked. I stuck it back on the charger just so I can bring it in to Batteries Plus with a full charge…or however full it gets since I plugged it in.
ETA, yes, the light is always on when the key is on.
Minor update:
I put in the new battery and it cranked much better. I redid some of my previous diagnostics and there wasn’t any change. I put the new plugs in and now I’ve got it running for 10-30 seconds at a time instead of 2-5 seconds. It could be that the existing problem was being exasperated by bad plugs or, hopefully, it was just running out of gas since all it had to work with was about a half a cup.
One thing I did notice is that after those few runs only the front cylinder (and exhaust pipe) were hot. The rear one was still cold. I checked the plugs and they all looked about the same. Hopefully in the next few days I’ll be able to get it running a bit longer. I’ll probably set the tank back on it with a half a gallon of gas or so. I’m working on the assumption that it just didn’t run for very long and (maybe) the rear cylinder has more mass to it.
I’m still open to more thoughts, but for the moment, I’m thinking there’s not too much more I can/should do until I throw the tank (and maybe the air cleaner) back on it.
ETA, not that it really matters since it never warmed up, but blipping the throttle or messing with the choke (closing it) kills the engine right away. Gradually opening the throttle will get me a few RPMs and a few more seconds, but not much. It’s still considerably more touchy then it was before.
Bolding mine.
I hope you mean opening it, as the choke should be closed (knob pulled out) until it starts (engine cold).
I have also found that continuing to crank a time or three after it fires while opening the throttle will get the revs up and allow it to idle with the throttle released, when cold.