Go Back   GZ 250 Forums > GZ250-Specific > Troubleshooting

Reply
 
Thread Tools Display Modes
Old 05-09-2014, 03:24 PM   #201
jonathan180iq
Super Moderator
 
jonathan180iq's Avatar
 
Join Date: Jan 2007
Location: Dalton, GA
Posts: 3,996
It's been the last year or so that all of these valve problems have been popping up... I don't remember being an issue for most of the life of this forum. All of the years of these bikes are different, and I haven't really kept up with mileage data. Maybe it's just that we have more members trying to fix a problem instead of people never posting and then just throwing their bikes, away. But it seems odd.

Anyway. The valve issue isn't something that happened because of you cranking the bike. A few different things had to fail all around the same time, and the broken gear and the subsequent searching for issues probably all boils down to this.

What kind of shape was your old head in? You'll also want the guides too. I don't recall the whole story. But if you have a good head on hand, then you're good to go. I'd just swap it over.



Login or Register to Remove Ads
jonathan180iq is offline  
Reply With Quote
Old 05-19-2014, 12:24 AM   #202
ImaginativeFig
Senior Member
 
ImaginativeFig's Avatar
 
Join Date: Jan 2014
Location: College Station, Texas
Posts: 138
I really don't think it's a valve problem. I hand cranked again with the head fully assembled and the valve windows open and the most resistance happens a bit before the intake valves open up, not during any valve movement.
So after hand cranking it a bunch and not encountering anything too bad, I decided to try with the key again. This time got a whole new sound. Just realized I didn't dump a whole new load of oil in there this time, so it was just going with the dregs that were left over after I took the side off 2 weeks ago.
No terrible sounds tonight, a familiar failing sound that I forget the meaning of. What causes this one?
ImaginativeFig is offline  
Reply With Quote
Old 05-19-2014, 10:04 PM   #203
gz4me +
Senior Member
 
gz4me +'s Avatar
 
Join Date: Sep 2013
Location: Santa Maria, California
Posts: 234
Thumbs Up Multi-problemed bike

I know this might sound stupid, but did you check for spark after putting everything back togeather?? Grandson and I still have not got his GZ going. Last time we took everything apart and then put it back and still would not start, We did find bad connection at pick-up coil to CDI connector. Fixed that and got spark back, but still no start for us. But did have spark back. Hang in there!!!! You are doing one hell of a job.



Login or Register to Remove Ads
gz4me + is offline  
Reply With Quote
Old 05-25-2014, 01:53 PM   #204
ImaginativeFig
Senior Member
 
ImaginativeFig's Avatar
 
Join Date: Jan 2014
Location: College Station, Texas
Posts: 138
Ok, I've check for spark, then a second time checked for spark with a witness. Spark is strong and purpley and jumping across the gap, which is the right distance.

When I'm holding the starter, the engine does turn over, there is air being pushed out of the exhaust (so my camshaft prolly isn't snapped again )

We tried starting it with starter fluid (actual starter fluid that I bought from the store, nothing approximate about it), no go, but we did get a reversion that scared me...

I also tried running starting it twice on Thursday. The first time I got two loud backfires,
the second time it started, but sputtered out.

so... what now?

Last edited by ImaginativeFig; 05-25-2014 at 02:09 PM.
ImaginativeFig is offline  
Reply With Quote
Old 06-13-2014, 05:47 PM   #205
ImaginativeFig
Senior Member
 
ImaginativeFig's Avatar
 
Join Date: Jan 2014
Location: College Station, Texas
Posts: 138
Oh No

Ok, since I had reason to believe I had spark, air, fuel, and compression, I started looking for timing or other stuff that could be wrong. I eventually found isaac's thread called "No start: Have spark, have fuel, have air" in which he discovered that his woodruff key had been shorn off, thus allowing the flywheel to misalign and screw up the ignition timing.
If you'll remember from last page (about a month ago), I intially didn't tighten my flywheel on tight enough, well, as it turns out, that destroyed my woodruff key.
It took some time to figure out how to get it out, since the protruding part was completely flattened/gone.
Turns out that the semi-circular shape means you just have to push down on one end (by, say, tapping an awl on it with a hammer) and the other pops up and can just be pulled out, so it's not really an excuse for your friend to build his arc welder, but whatever, we got it.

I put a new one in today with great hopes that it would go, but it didn't. It was hot and it took us a long time to tighten everything down on my bike all proper-like, but yeah, it won't go. Turn over sounds, no catching. I'll take another look at it sometime next week, I guess.



Login or Register to Remove Ads
ImaginativeFig is offline  
Reply With Quote
Old 06-13-2014, 10:47 PM   #206
k1w1t1m
Member
 
Join Date: Nov 2009
Location: Centerton AR USA
Posts: 36
Are you sure the cam timing is correct? I've never been inside one of these, just throwing an idea out.
k1w1t1m is offline  
Reply With Quote
Old 06-16-2014, 09:15 AM   #207
ImaginativeFig
Senior Member
 
ImaginativeFig's Avatar
 
Join Date: Jan 2014
Location: College Station, Texas
Posts: 138
It's definitely something I'll have to check again.
I'm missing the white line on the cam sprocket that's supposed to be at the front when it's timed, so even if did have it rightish, I may still be 180 off.
ImaginativeFig is offline  
Reply With Quote
Old 06-17-2014, 03:46 PM   #208
k1w1t1m
Member
 
Join Date: Nov 2009
Location: Centerton AR USA
Posts: 36
Quote:
Originally Posted by ImaginativeFig View Post
I hand cranked again with the head fully assembled and the valve windows open and the most resistance happens a bit before the intake valves open up, not during any valve movement.
This is what makes me think cam timing. The most resistance should be just before the exhaust valves open.
k1w1t1m is offline  
Reply With Quote
Old 06-18-2014, 10:32 PM   #209
5th_bike
Senior Member
 
5th_bike's Avatar
 
Join Date: Oct 2007
Location: HoCo, Maryland
Posts: 1,349
Quote:
Originally Posted by k1w1t1m View Post
This is what makes me think cam timing. The most resistance should be just before the exhaust valves open.
I think you're right, however the most resistance is on the compression stroke, and both valves remain closed, then. So "just" meaning, after the piston goes down from the compression.

The exhaust valve should then remain open until the piston is at the top again. That is when the inlet valves should start opening. And the inlet valves should close when the piston is down again. Then, all valves should remain closed when the piston goes up, to the compression.
__________________
2005 "Saturn Black", stock + tach
5th_bike is offline  
Reply With Quote
Old 10-05-2014, 05:51 PM   #210
ImaginativeFig
Senior Member
 
ImaginativeFig's Avatar
 
Join Date: Jan 2014
Location: College Station, Texas
Posts: 138
It was the woodruff key again. This time it didn't get shredded, it had just gotten pushed out when I was putting the rotor on or something.
Then the carb was gunked up and needed cleaning,
here's what it's doing now, what do you guys think I should do about it?

Last edited by ImaginativeFig; 10-05-2014 at 05:53 PM.
ImaginativeFig is offline  
Reply With Quote
Reply



Tags
electrical, oil, problems, troubleshooting, won't start

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:14 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.