vinpickering
XS400 Member
Ok, so long story short my '80 XS400 has been off the road for over a year as I (slowly learnt to paint, then) repainted it. I took it for it's first ride in that long and it was glorious. It and I was loving it. So then I thought I'd ride it to work, and it got there fine but then when I tried to leave it wouldn't start until I'd tried kicking it for about 20 minutes. I had an audience and everything by then end. A guy even clapped when:
Eventually it started, and I was so scared of it stalling (and taking another 20 minutes to start again) I was blipping it and keeping it revving at about 2000rpm at the first set of lights. I took off fairly quickly but after about 100m it died at the top of a hill. It literally just sounded like a "Pfft" and then the revs were at zero and I was coasting down the hill. I first thought the battery had disconnected itself but all the electronics were on. I was still coasting, even dropping the clutch to hope it would hill start but it just kept coasting, not slowing down at all, telling me I had no compression at all. Eventually it stopped halfway up another hill and I tried kicking it again after shifting through the gears a few times and it was the same. I could even kick it in gear and I'd just hear this "whir-whir-whir" of the piston just going up and down with little resistance, and definitely no sparky sounds. I could also even push it while in gear. But, putting it in neutral, I had a long walk pushing it home to mull over what I thought might have happened...
My first thought was the drive chain, but it was still attached. Then I thought gear box, but that didn't seem right. It seemed to me like the top end wasn't talking to the bottom, because there was no spark when I kicked it. Cam Chain was my theory by the time I was home, but by then it was dark and I was swimming in my jeans and work shirt with sweat, so it would have to wait till I could find out.
First thing I did when I got back to it was take off the point cover and kick the engine over again (I could do it by reaching over and doing it with my hand, there was so little resistance). Cam shaft didn't move. Cam chain was sounding about right. I then took off the valve covers and saw the attached. Can you spot the difference? Yep, the left inlet valve doesn't have a lock nut. Makes me sick to think where it might be and what it might have done in there.
So, anyway, my questions for you guys are:
As you might be able to guess, I REALLY don't want to take the engine out, because I don't have a bench to put it on anyway, or, I'm assuming, the strength to mount it back on again by myself once I'm done.
The factory manual gives you instructions I'm sure I can follow (and I've seen other forum topics that say this), so that's not the issue, I'm more after some rough guidance, rather than a how-to.
Any help/sympathy is appreciated.
Eventually it started, and I was so scared of it stalling (and taking another 20 minutes to start again) I was blipping it and keeping it revving at about 2000rpm at the first set of lights. I took off fairly quickly but after about 100m it died at the top of a hill. It literally just sounded like a "Pfft" and then the revs were at zero and I was coasting down the hill. I first thought the battery had disconnected itself but all the electronics were on. I was still coasting, even dropping the clutch to hope it would hill start but it just kept coasting, not slowing down at all, telling me I had no compression at all. Eventually it stopped halfway up another hill and I tried kicking it again after shifting through the gears a few times and it was the same. I could even kick it in gear and I'd just hear this "whir-whir-whir" of the piston just going up and down with little resistance, and definitely no sparky sounds. I could also even push it while in gear. But, putting it in neutral, I had a long walk pushing it home to mull over what I thought might have happened...
My first thought was the drive chain, but it was still attached. Then I thought gear box, but that didn't seem right. It seemed to me like the top end wasn't talking to the bottom, because there was no spark when I kicked it. Cam Chain was my theory by the time I was home, but by then it was dark and I was swimming in my jeans and work shirt with sweat, so it would have to wait till I could find out.
First thing I did when I got back to it was take off the point cover and kick the engine over again (I could do it by reaching over and doing it with my hand, there was so little resistance). Cam shaft didn't move. Cam chain was sounding about right. I then took off the valve covers and saw the attached. Can you spot the difference? Yep, the left inlet valve doesn't have a lock nut. Makes me sick to think where it might be and what it might have done in there.
So, anyway, my questions for you guys are:
- About how screwed do you think I am?
- Can I take off the top end without removing the engine from the frame?
- Will I be able to replace the cam chain (if that's still the main issue) without removing the engine from the frame?
As you might be able to guess, I REALLY don't want to take the engine out, because I don't have a bench to put it on anyway, or, I'm assuming, the strength to mount it back on again by myself once I'm done.
The factory manual gives you instructions I'm sure I can follow (and I've seen other forum topics that say this), so that's not the issue, I'm more after some rough guidance, rather than a how-to.
Any help/sympathy is appreciated.