| Author | Message | ||
     Jvgardner02 |
Hello all, new to this forum and to the Blast. Recently bought a 2006 Blast as a starter bike for the wife. Found a bike with 30 miles on it (been sitting a while for sure)....checked it out and everything looked great. Rode it for a while, ran great, so I bought it. Rode to gas station and put fresh 93 in... and it would crank up at the pump in neutral, then die when putting it under load. Figuring it had varnish and gunk in the carb after sitting so long w/ 10 year old gas, I drained gas tank, pulled the carb and fully cleaned it. NOW...it cranks up and rides fine for about 5 minutes, then slowly sputters and dies. I know its nothing with the fuel line because I've cleaned the carb, pulled the tank, cleaned petcock filter, etc. Also, everything is brand new...30 miles on the bike... Any ideas on this are greatly appreciated! | ||
| Gearheaderiko |
Replace the slow/pilot jet with a #45 (stock on many many Harleys. HD Should have it in stock). $6-$10 | ||
| Jvgardner02 |
Thanks for the quick feedback! Would your advice change if I added in the info that after the bike dies, it won't start for a few minutes? I can let it sit for a few, then crank it back up. It will run for a bit, then sputter die again, even when goosing the throttle. Not sure if that changes the analysis.... | ||
| Gearheaderiko |
You're going to need a #45 regardless. Slow jet is the one thing that commonly clogs up from sitting for a looong period of time. It also has the symptoms you describe. You'd have to change it anyway, whether it's good or bad. The stock #42 is too lean and it runs and starts better with a 45. Hopefully you didn't mess the carb up taking it apart. That's very common too  | ||
| Jvgardner02 |
Thanks for the advice! I will call the HD dealer today to pick up a new slow jet. What are some common problems you've seen with people taking the carb apart? Other than float height, I don't really see anything else in there than can go wrong if everything goes back together properly. Something specific to this carburetor that you have seen go wrong that I should look out for? | ||
| Gearheaderiko |
You name it, it gets messed up. It's a very simple carb, but more often than not a post starts out with "I took my carb apart to give it a good cleaning and now my Blast won't run right". Fact is a Blast carb rarely needs "a good cleaning". Carb problems can be traced to a single system in the carb and most often it's a clogged slow jet or a malfunctioning auto enrichener. However after the carb gets taken apart by the unknowing, it could be a bunch of things completely unrelated to the problem (if there even was a problem). | ||
| Jetlee |
Most often it doesn't go back together properly, and that's where the problems begin. How to "clean" a Blast carb: 1. Remove fuel bowl 2. Remove cap and slide 3. Use whole can of carb cleaner to spray the hell out of orifice and crevice 4. Re-assemble That's it. (Message edited by JetLee on June 17, 2016) | ||
| Jvgardner02 |
Ok, so I have replaced the slow jet, boot, and airbox/carb gasket. Brand new parts. Once I got everything back together on Saturday it did fire up, but was still trying not to idle. I checked the idle mixture screw and it was off, so I set it at 2.5 turns from the bottom. Fired it up, and it ran great. Put about 10 miles on it around the neighborhood just to run it, and it was really running and idling fine. Left for the 4th weekend, and came back today and it won't crank again. It fires up every now and then and idles extremely low, and giving it any throttle kills it. I don't understand what can make the thing so temperamental..... Thanks in advance for an ideas! Thing is testing my patience.... | ||
| Ezblast |
Bad gas? EZ | ||
| Jvgardner02 |
I don't think so.... I have completely flushed the tank and added in fresh premium from a well-traveled gas station. After posting last night it stopped starting at all....it will start for a moment with a spray of starting fluid, but otherwise nothing. A mechanic buddy of mine is convinced it just needs to be run, and that it will work the kinks out. But can't run it if I can get it to start and STAY running! | ||
| Jvgardner02 |
Update: This afternoon I could not get the bike to start, yet again. Tried "manually" choking it by holding my hand over the carb while the wife held the clutch in. It started up, and would run a little, but eventually sputter and die again when I removed my hand. If it did stay running when I removed my hand, giving it throttle it kills it. Auto-enrichener maybe? Admittedly I am pretty ignorant beyond the basic carb system (TPS, auto-enrichener, etc). And I can clearly tell that taking the carb apart is not recommended by the experts here, and I understand why for sure! But I am pretty confident that everything went back together properly. Hoping this problem is something else... | ||
| Gearheaderiko |
If the AE is bad, the bike will run after its warmed up. It will be okay in the summer months and if you've replaced the slow/pilot jet with a #45, you won't have much of a problem at all. If this all started after you took the carb apart, then that's the problem. The CV carb is very simple. It being complicated is not why I say don't take it apart. Experience has proven that taking the carb apart by the inexperienced very very often leads to problems. The second and probably must important, is the carb rarely ever needs cleaning and rarely ever has a problem where wholesale disassembly is needed. Its just like an engine with separate operating circuits, you just need to diagnose which circuit is faulty. As always, check "Das Boot". New ones have been improperly installed causing problems too. | ||
| Jvgardner02 |
Thanks again for the feedback. The problems definitely started prior to taking the carb apart. How it was running, the fact that it had been sitting for years, and my experience with other engines led me to believe that a carb cleaning was in order. It was really dirty, so I don't think it was in vain, but I was unaware of repeated issues with disassembly of this particular carb. But assuming that my problem is with the fact that I disassembled the carb, in your experience where is the best place to start trying to remedy that problem? I will check the float height to be sure that it is accurate. But aside from checking that all other parts are assembled correctly (I followed the service manual to the letter in both disassembly and reassembly) what are some common things you've seen that I could check for actually inside the carb itself? I switched the clutch safety so I could start it solo. Still am able to sometimes start it with my hand over the carb throat, but remove my hand and it dies. Getting strong suction at the carb throat. Sorry if it seems like I'm asking the same questions, just trying to get to a solution if my disassembly of the carb is the root of the problem. (Message edited by jvgardner02 on July 06, 2016) | ||
| Gearheaderiko |
Okay, it won't stay running, not even enough to get it warm, right? Hand over the carb and it will start says you have a lean condition. With a #45 slow jet and this being summer, it should stay running long enough for you to get it warm enough to ride it. Common carb disassembly/reassembly problems that may relate to your issues are the needle guide falls out unnoticed or get put in backwards (small barrel shaped piece at the bottom of the carb mouth that the needle slides in and out of). Rubber diaphragm on top of carb is installed wrong, pinched or not sealing. O-ring, washer or spring gets left off the idle mixture screw. Das Boot!! Don't assume it's good if it looks good on the bike. Slices in the boot can close perfectly if still on the bike. If you shimmed the needle, remove the shims. If you removed the auto enrichener, you'll have to check it for proper reassembly (if you didn't touch it, DONT!) Did you remove the intake manifold? I've probably asked this but: did it ever run okay for you? Is there anything (anything, seriously*) that you did before you had problems. * beyond carb problems, I can't tell you how many pages of posts I've gone through to have someone finally say what they did right before the problem started or some unrelated mod (or so they thought) they did that immediately preceded the problem. It just happened on another thread!!! | ||
| Gearheaderiko |
Also: rubber vacuum nipple cap on carb. Is it there? In good condition? | ||
| Jvgardner02 |
Awesome, thanks! I did not do a thing to it before having problems other than fill it up with gas. I literally rode it to test ride it before buying, and then after I paid the dude I rode to the gas station to fill it up. Upon fill up, bike wouldn't run under load. Thats what got me thinking that the fill up dislodged some gunk somewhere and clogged up something in the carb. Or new gas mixed with old gas...same problem. I have not touched the AE, and won't. I will go through the carb and check for each of these things you mention. I know the vacuum nipple on the carb is there and in good condition. Did not remove intake manifold, and did not shim the needle. Any tricks to getting a good seal on das boot? I'm just using brand new hose clamps on a brand new boot I got from the HD dealership. Will check all of the other things you mentioned, and also move through the service manual assembly instructions to be sure I did everything correctly. Again, thanks for the help. | ||
| Gearheaderiko |
The carb just "clicks" in to the boot, likewise with the manifold. Just don't overtighten the clamps. If you start to see the boot edges mushroom or distort, you've gone a little too tight (just a little. Right before it distorts or mushrooms is good). If you have a compression tester, test the compression. |
