Problem starting my 81 Yamaha XJ 550 Maxim - 9000 miles
Posted: Mon Oct 24, 2005 8:08 am
This is my first bike and first time working on one, so all the help you could give would be awesome. Here's a breakdown of what's going on:
Problem:
Battery is turning the engine, but after 10 seconds of holding the ignition switch there just won't be any combustion. The bike was riding fine in the summer, but if I didn't ride it for a week it would have some trouble firing up. All I would have to do there was to pull the choke all the way back and it would start after a couple trys. The first time it didn't start was after that week long monsoon we had up here in the Northeast (I'm in Philly). At that point, the bike had been sitting for a week. It was covered and out on the street.
Since then I've tried multiple things to get it working:
Ignition - checked the spark plugs and they were in good condition. Each one was producing a good spark. I went ahead and bought new sparks anyway and installed them. Tested the new ones to make sure they were sparking and they were. When I was replacing the 4th cylinder spark, I put my hand over the hole when I hit the ignition switch, and I felt a gust of air come from the cylinder. Didn't check the other three for this, but I assumed they are working fine since I'd be hearing a different noise if the pistons were stuck.
Petcock - Removed the vacuum and fuel lines at the petcock. Set the valve to Prime and the gas poured out. Attached the vaccuum line back to the petcock, put the valve in the "ON" position, cranked the engine and gas was coming out. Therefore the vaccuum line and the fuel lines are ok.
Airfilter - Replaced
Carbs - Took them off today thinking I'd find the problem there, but they were extremely clean! Still removed the jets and blew them out with cleaner. There were no apparent obstructions. Cleaned it up, lubricated joints, and reassembled. Put the petcock on Prime for 5-10 seconds to fill the float bowls on the carbs, switched the valve over to "ON" and tried starting. No luck.
So what could be left? One thing I did notice was that on the middle side of the 2nd and 3rd cylinders, where the cylinder body meets the top cam cover, there are some wet spots coming from the gasket. Would this prevent the bike from starting? Any help would be greatly appreciated. If you need anymore info, let me know. Thanks!
Alex
Problem:
Battery is turning the engine, but after 10 seconds of holding the ignition switch there just won't be any combustion. The bike was riding fine in the summer, but if I didn't ride it for a week it would have some trouble firing up. All I would have to do there was to pull the choke all the way back and it would start after a couple trys. The first time it didn't start was after that week long monsoon we had up here in the Northeast (I'm in Philly). At that point, the bike had been sitting for a week. It was covered and out on the street.
Since then I've tried multiple things to get it working:
Ignition - checked the spark plugs and they were in good condition. Each one was producing a good spark. I went ahead and bought new sparks anyway and installed them. Tested the new ones to make sure they were sparking and they were. When I was replacing the 4th cylinder spark, I put my hand over the hole when I hit the ignition switch, and I felt a gust of air come from the cylinder. Didn't check the other three for this, but I assumed they are working fine since I'd be hearing a different noise if the pistons were stuck.
Petcock - Removed the vacuum and fuel lines at the petcock. Set the valve to Prime and the gas poured out. Attached the vaccuum line back to the petcock, put the valve in the "ON" position, cranked the engine and gas was coming out. Therefore the vaccuum line and the fuel lines are ok.
Airfilter - Replaced
Carbs - Took them off today thinking I'd find the problem there, but they were extremely clean! Still removed the jets and blew them out with cleaner. There were no apparent obstructions. Cleaned it up, lubricated joints, and reassembled. Put the petcock on Prime for 5-10 seconds to fill the float bowls on the carbs, switched the valve over to "ON" and tried starting. No luck.
So what could be left? One thing I did notice was that on the middle side of the 2nd and 3rd cylinders, where the cylinder body meets the top cam cover, there are some wet spots coming from the gasket. Would this prevent the bike from starting? Any help would be greatly appreciated. If you need anymore info, let me know. Thanks!
Alex