Thread: Gp1200 Rebuild Help
04-13-2009, 05:17 PM #1
I had 0 compression in the Mag Cylinder at the end of last season and decided to wait until this spring to rebuild. I just finished taking the engine out and apart to try to figure out the cause of this. I found half of washer chewed up inside my engine!!! From the looks of it, this might have been the cause to why the piston ended up fried. What i need help with is, could the washer be the culprit to this problem? Can the cylinder be re-sleeved or is it toast? Pretty sure the head is toast? Are the cases fine? I have pictures to add that shows the damage and to where.
Last edited by Hockey369; 07-02-2009 at 12:09 PM.
04-13-2009, 05:22 PM #2
04-13-2009, 05:26 PM #3
04-13-2009, 05:30 PM #4
04-13-2009, 06:39 PM #5
well i see what happined.....take a real close look at your rear seal next to the coupler......is that a break cut out of the seal?
cases can be saved just sand out the nicks and dings.... heads are cheap... buy a sleeve and have the damaged cylinder resleeved. Have the crank checked... hows the bearings?? New piston, seals, and gaskets and your good to go. Do some of the work yourself and it could be done for under 500 bucks.
04-13-2009, 06:44 PM #6
Check the fuel pumps in all three carbs! This is the cause of most engine blow ups in the 65U engine. Where did the washer come from? You will need to track this down to ensure it does not happen again. Understanding why the engine failed is key to ensuring your rebuilt engine wont self destruct straight away .
04-13-2009, 06:56 PM #7
- Join Date
- Aug 2006
I have run worse heads just sand down the high spots since non appear to be in the dome'
are u sure it wasn't a ring snag ?
04-13-2009, 08:51 PM #8
Where was the washer ? and where are the pics of the washer ? what kind of washer ?
04-13-2009, 09:47 PM #9
Both seals were good on the crank. The bearing feel good and are still smooth but i will get the crank check anyways...never can be too sure.
Im also planning on rebuilding the carbs since i will have it apart and will be waiting on parts i will have the time.
It could have been a ring snag. I'm not quite sure which is one of the reason for the post.
You can see the washer in the pic with all the parts. Its the half washer in a pile of crap next to the burnt up piston. That i found in the intake manifold. I will take a better pic of the washer.
04-13-2009, 09:55 PM #10
Better pics of the washer. I only found one half. This is the top and bottom.
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