Post by cleaveunto on Nov 27, 2010 14:14:26 GMT -5
Help. Low to non-existent manifold vacuum. Fuel petcock won't stay open when engine is running. Stalling (out of gas) when running under load with wide-open throttle. Engine will start after much cranking then run fine until it stalls under load again.
So far, I have: Replaced all the vacuum and fuel lines. Replaced the fuel petcock. Replaced the fuel filter. Installed a vacuun guage.
Post by cleaveunto on Nov 27, 2010 15:08:34 GMT -5
I bought this honda 250 with this problem.Here is a post from previous owner: OK, I'll run down what I've tried and the results - my diagnosis is burnt valves or a trashed inlet valve stem seals. Symptoms: Faint blue smoke. Low to non-existent manifold vacuum. Fuel petcock won't stay open when engine is running.
Stalling (out of gas) when running under load with wide-open throttle. Engine will start after much cranking then run fine until it stalls under load again.
So far, I have: Replaced all the vacuum and fuel lines.
Replaced the fuel petcock. Replaced the fuel filter. Installed a vacuun guage.
Tests: Checked compression and timing and both are within acceptable values. Individually plugged each and every vacuum connection to check for leaks.
Removed all the vacuum lines except the one leading from the carb to the air valve, confirming the air valve works and there is manifold vacuum when the engine is running. Vacuum when the engine is warmed up is less than 5" HG. Done the tradition propane torch leak test with no leaks found. Removed and re-installed the carb. Double and triple-checked vacuum hose routing against the photos on Randy's website and the service manuals.
Wiggled, thumped, pounded and removed& re-installed the intake manifold to check for leaks or cracks.
If I pypass the fuel petcock and run a line directly from the fuel tank to the carb, it starts and runs fine but I still have zip manifold vacuum.
If I connect a vacuum pump to the fuel petcock, cap off the vacuum line running from the manifold to the fuel petcock, and start the engine it runs fine, but the manifold vacuum still reads very low.
I'll try any suggestions of what to look for or check. Thanks for the help
Weird.... not sure if you have the Honda Helix clone engine but I do. I nearly went crazy trying to figure out why my bike wouldn't start, replaced all fuel/Vac lines and still the same problem. Took out the fuel valve and ran a line straight from the carb to the fuel tank andit started everytime. I remember being a noob and adjusting the valves over and over without the piston being on TDC. This caused a horrible compression problem and led to little to no vacuum and the intake manifold was actually spitting OUT gas and air. My bike starts up everytime wether cold or hot, but the only problem is that when I ride my dad on the back lol ( he's. No more than 200lb) it stalls out when we come to a stop 70% of the time, I already made sure any hose weren't pinched. The rpms rise back up once he hops off. This is crazy!
Make sure all your vacuum hoses are hooked up correctly!!! This is the first thing that i would guess it wrong!! After this is would pull the carb and go through that. if it still doesnt work, Buy a new petcock off EBAY!! they are like 20 bucks!! If all this doesnt work, go to the source! check the gas tank. I bought an elite once that had its tank RUSTED out with a liner in it! the liner was floating around clogging the petcock screen! definently check the tank.
My first thought though would definently be that the vacuum lines are hooked up incorrectly. Let me know what you think! bookmarked ya!
The most likely problem You have is the intake Manifold , the little rubber Boot between the Carb and the Cylinder Head they crack very easy and then You get a Vacuum leek, A very common Problem with the Elite and Helix Engines .
wereed: HOw can I start a thread?
Jun 1, 2013 10:55:49 GMT -5
wereed: or respond to a thread I started three years ago...
Jun 1, 2013 10:56:07 GMT -5
marklorenzi: I just bought one of the Fleetwoods. They look like a clone of the Honda XRM's they sell overseas. It is in transit now and I should get it this week. I will try to post my experience here. Call me the guinea pig hahaha.
Jun 2, 2013 20:29:11 GMT -5
flyangler: wereed, this forum is read only the new forum is on the banner above. Dan
Jun 5, 2013 7:35:29 GMT -5
silkyg1973: can someone please tell me how to post
Jun 10, 2013 12:08:46 GMT -5