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-   -   Rebuilt the engine! (http://www.gz250bike.com/forum/showthread.php?t=2901)

MLGTIB 02-14-2010 09:33 AM

Rebuilt the engine!
 
Hey everybody. So I have an 05 GZ with about 6100 miles on it. Since I bought it in September, I noticed that every time I started it up it would make this popping sound. I recently took it to the dealer to replace the brakes and the mechanic noticed it to. When I went to pick the bike up he informed me that on the front of the engine there was a nut missing and the stud was just hanging freely. So I ordered up a whole bunch of parts and got to work. I replaced the head gaskets, all the studs, and Piston rings since I was already in the engine. I finished all the repairs yesterday and when I started her up it was beautiful, not a single noise other than the engine running of course. It sounds like a new bike. In order to remedy this problem from happening again I just added some locktite to all the studs. I rode it for about 50 miles and am very happy with the results. Once I have a chance to upload a short video of the first start up I will. :2tup:

alanmcorcoran 02-14-2010 03:31 PM

Re: Rebuilt the engine!
 
I think a lot of the mechanical types on here will be looking forward to seeing your movie.

Did you order the parts from Suzuki or somewhere else?

Easy Rider 02-14-2010 07:42 PM

Re: Rebuilt the engine!
 
Quote:

Originally Posted by MLGTIB
When I went to pick the bike up he informed me that on the front of the engine there was a nut missing and the stud was just hanging freely.

I'm really glad that all turned out OK but........
It is highly unlikely that ALL THAT needed to be done on a bike with that kind of mileage. I suspect that you have more mechanical skill and experience than about 99% of the people here and a "do it yourself" rebuild of that magnitude would probably NOT be a wise undertaking for most.

Just exactly what WAS the part that was loose ??
Could you not have just fixed THAT without doing all the rest ??

burkbuilds 02-14-2010 09:07 PM

Re: Rebuilt the engine!
 
It does sound like a lot at first read, but when I went back and read the original post again it looks like the only thing you did that was probably unnecessary was the new rings. I guess if you've got the engine out and all, popping a set of rings in isn't really a big deal on a one cylinder engine, and with no more mileage than you had on it, you probably didn't even need to hone the cylinder. Otherwise just gaskets, studs and nuts.

MLGTIB 02-14-2010 09:12 PM

Re: Rebuilt the engine!
 
The cylinder head nut that was missing was the one just below the two exhaust ports on the front of the engine. In addition, the actual stud that it screws on to had come lose and was resting on the cylinder base below it (it doesn't fall out and get lost, but falls out and remains loose in its bore), and that created the leak in the head, which creates the popping noise on initial startup. After heating up, that usually goes away since the engine expands with the heat and seals the gap well enough. Since I had to remove so much of the cylinder head it required me to replace all the gaskets. Although I didn't HAVE to replace the rings or cylinder base gasket, I figured I might as well for my own peace of mind. As for experience, I have a bit but I have never done anything to this extent. I used the service manual which has good instructions. The only thing that I recommend is to download the word doc version because in the section that explains how to install the new piston rings there is a picture that is on top of a diagram that shows you how the gaps of the rings should be positioned.

The dealer wanted $400 to do the job, where I did it for the cost of the parts which came out to be around $75. If you are a person who wants to learn more about how the engine works and how to do the repairs yourself than this is the engine to do it on. It was pretty easy to do, just have to have a little patience and go slow to make sure you get it right. Best of luck to all that jump in on the engine repairs. :2tup:

Maggie 02-15-2010 01:29 AM

Re: Rebuilt the engine!
 
Hey MLGTIB! Looks like we're neighbors...I'm in West Van Nuys (basically Reseda!). I am totally inexperienced with any kind of mechanical work, but really want to start doing the work. Maybe next time you do dome basic work on your GZ I could bring mine over and watch you? Then maybe I'll get the courage to try something like an oil change (I love reading the "how to" posts, especially with the pics!)

MLGTIB 02-15-2010 09:28 AM

Re: Rebuilt the engine!
 
Quote:

Originally Posted by Maggie
Hey MLGTIB! Looks like we're neighbors...I'm in West Van Nuys (basically Reseda!). I am totally inexperienced with any kind of mechanical work, but really want to start doing the work. Maybe next time you do dome basic work on your GZ I could bring mine over and watch you? Then maybe I'll get the courage to try something like an oil change (I love reading the "how to" posts, especially with the pics!)

Hey Maggie, I will try to keep you in mind when I need to do something. Oil changes are the easiest thing to to. When its time just let me know. On a side note, I am always looking for someone to ride with. Hit me up anytime. I will get the pixs and video up later today for everyone to see. :rawk:

trykemike 02-15-2010 12:50 PM

Re: Rebuilt the engine!
 
Hey MT !

When I had put 1000km on my bike i examined the engine and noticed what appeared like an oil sweat between the exhaust pipes at the gasket . I also tightened the nut that is there between the pipes and used blue locktite. That resolved the oil leak. There is a similiar nut under the carb at the back of the head snug it up also. Check the manual for a detailed picture.

MLGTIB 02-20-2010 09:26 PM

Re: Rebuilt the engine!
 
Here is the video of the First Start up. Please excuse the poor quality, I used my iPhone to record it.

http://i705.photobucket.com/albums/w...terrebuild.jpg

alanmcorcoran 02-20-2010 09:50 PM

Re: Rebuilt the engine!
 
Pretty good quality for iphone!


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