Author Topic: How do I set the timing on the Grandvista 250..?  (Read 2360 times)

maninbabylon

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How do I set the timing on the Grandvista 250..?
« on: November 10, 2017, 10:25:47 PM »
I recently purchased a used 2009 Grandvista 250 that needed a new piston. So, all the work was done and everything is almost back together.  The problem I'm having is "How do I set the timing???"  I know what to do with the cam shaft, but where the heck is the "T" for Top Dead Center or where is the marking for top dead center...?  Where is the T on the flywheel...? 
« Last Edit: November 10, 2017, 10:45:18 PM by maninbabylon »

big blue

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Re: How do I set the timing on the Grandvista 250..?
« Reply #1 on: November 11, 2017, 10:35:29 PM »
Take a look at this post from this forum...http://www.kymcoforum.com/index.php?topic=11412.0
2012 Kymco Like 200i LX (Sold)  Salem, Oregon USA

mrbios

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Re: How do I set the timing on the Grandvista 250..?
« Reply #2 on: November 13, 2017, 04:14:41 AM »
There is no 'T' mark on the cam gears.  The manual describes the position as the two holes are in a horizontal position.  See attached picture.

Here's a link to my head gasket repair for the Grandvista. 

https://drive.google.com/open?id=1axfPrnVPtCOXlIYzgEnq70ZsuuU7uOWo

Here's the Manual:
https://drive.google.com/open?id=1FlbbsvqRyUhEbKYK8ZDCri5QmZNOlT8M

What happened to the piston?
PaulC

maninbabylon

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Re: How do I set the timing on the Grandvista 250..?
« Reply #3 on: November 28, 2017, 07:23:07 PM »
Thank you for the responses... they really helped.  I was able to properly set the timing. The bike over heated and fried the piston, it literally melted and popped a hole in the piston.  The cylinder was surprisingly still in good shape and just needed some lite sanding. After replacing the piston, rings, pin, clips, gaskets, valves, flushing out the engine... I put it all back together and it cranked right up and ran for a bit until it over heated.  So, I checked the waterpump and the impeller was free wheeling.  I opened up the right crank cover and discovered the real reason the bike overheated and fried the piston.  The circlip that holds the gear that connects to the small drive shaft for the waterpump and oilpump was gone...(huge design flaw in my opinion) so, no waterpump or oil pump. I replaced the circlip and put evrything back together and tried to start it and the starter motor fried. I have replaced the starter motor and all it does is grind a bit.  Now I have a short somewhere that is keeping it fromk starting.

mrbios

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Re: How do I set the timing on the Grandvista 250..?
« Reply #4 on: November 28, 2017, 09:02:22 PM »
Thank you for the responses... they really helped.  I was able to properly set the timing. The bike over heated and fried the piston, it literally melted and popped a hole in the piston.  The cylinder was surprisingly still in good shape and just needed some lite sanding. After replacing the piston, rings, pin, clips, gaskets, valves, flushing out the engine... I put it all back together and it cranked right up and ran for a bit until it over heated.  So, I checked the waterpump and the impeller was free wheeling.  I opened up the right crank cover and discovered the real reason the bike overheated and fried the piston.  The circlip that holds the gear that connects to the small drive shaft for the waterpump and oilpump was gone...(huge design flaw in my opinion) so, no waterpump or oil pump. I replaced the circlip and put evrything back together and tried to start it and the starter motor fried. I have replaced the starter motor and all it does is grind a bit.  Now I have a short somewhere that is keeping it fromk starting.

That's some impressive work.

Here is a general FYI on digital ignitions aka CDI for motorcycles and most cars:

Page 17-1 of the manual:
"The ignition system adopts CDI unit and the ignition timing cannot be adjusted."

The only "adjustment" for timing it to make sure the timing chain / cam gears, cam shafts are in the TDC position. 

I'm not sure how the circlip came off but I've never had that problem on any scooter/ mc / atv and I have 23K on my 2005 Grandvista and I run it at 80-100% throttle on the highway most of the time.

Recommendations:
1. Don't use the starter until you crank the motor by hand by removing the cover and using a socket and ratchet.  Depending on what you experience you might want to remove the valve cover and verify torque and timing of the motor - TDC mark. 
2. Check valve clearance AND feel for resistance from compression.  Too low compression = no start.
3. Remove the spark plug and crank the engine first by hand and then with the starter.  When using the starter check for a visible and sound of a spark.
4. Report results to this thread.

Note: anytime the cooling system is disturbed or flushed remove the front plastic piece to directly access the radiator to remove the cap, expel trapped air and observe that there the coolant is circulating especially when the motor is revved.  After the thermostat opens you can dip your finger or grab the hose to feel for warm / hot coolant.  If you don't get that there is a problem: trapped air (most common), thermostat not opening, or in your case water pump is not spinning. Never flush the coolant and refill from the reservoir without accessing the radiator as that will result in trapped air and overheat the engine after about 10 minutes of idling /driving.

2.
PaulC

maninbabylon

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Re: How do I set the timing on the Grandvista 250..?
« Reply #5 on: December 02, 2017, 08:20:53 PM »
Thanks MrBios for the info... I guess I did all I could do for the timing considering the info you shared. Everything is in TDC.  As for my new problem. As I said, I removed the right crank case cover and replaced the circlip on the drive gear that connects it to the drive shaft of the water pump & oil pump and then put it back together, new gaskets etc, filled with new oil and coolant (and yes I have the front of the scooter off so I can access the radiator) and then I went to start it and the starter solenoid clicked and the starter motor did a grunt and then nothing. Keep in mind, it was running before I replaced the circlip, when I removed the right crank case cover no electrical wires need to be touched. After this, I pulled out the starter motor and found that it was fried on the inside, melted. So, I ordered a new one and started looking at my grounds. That's when I found my main power line melted to the main ground wire in three spots.  Whatever happened when I tried to crank it the first time caused them to melt and ground out.  I fixed those wires and installed a new starter motor and now nothing happens. The solenoid clicks and the motor does nothing.  I ook the motor out and tested it and it runs great.  I can turn the fly wheel by hand, but I think the only thing it can be at this point is the starter clutch...  Any suggestions...?
« Last Edit: December 02, 2017, 10:33:53 PM by maninbabylon »

mrbios

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Re: How do I set the timing on the Grandvista 250..?
« Reply #6 on: December 02, 2017, 11:43:02 PM »
Thanks MrBios for the info.....
...  Any suggestions...?

Your welcome and excellent work and thanks for reporting your results which helps everyone. 

Starter clutch is suspect.  Good that the motor cranks by hand. If it was a motorcycle you could roll start it.

Starter clutch... when they fail it is usually two possibilities - stuck engaged - engine cranks  but after the engine starts the clutch will not disengage and the starter keeps spinning.  Other possibility is failure to engage - usually the starter will spin fast but the engine won't turn.  If it just clicks that could mean a lack of power - so you might want to directly connect the battery positive to the large main wire on the stater.

Keep me posted on your progress I feel like you are getting close.
PaulC

maninbabylon

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Re: How do I set the timing on the Grandvista 250..?
« Reply #7 on: December 04, 2017, 07:52:39 PM »
Ok, here's the final update on my problem.  Through this whole process I have learned that Kymco engineers these motors to the finest of tollerances. When I removed the right crankcase cover I did not have an OEM cover gasket to replace the old one, so I went out and purchased the Gasket maker stuff in a tube.  This was the mistake.  It turns out the starter gear is held in place with a dowel that is held in place by the engine body and cover. If you do not use an OEM gasket the cover will pinch the starter gear and not let the starter motor turn at all.  After backing out the screws just ever so slightly, the starter worked great. So, I am waiting on my OEM gasket to arrive from Israel.

mrbios

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Re: How do I set the timing on the Grandvista 250..?
« Reply #8 on: December 04, 2017, 08:23:02 PM »
Ok, here's the final update on my problem.  .... So, I am waiting on my OEM gasket to arrive from Israel.

Wow!  What an exciting update!  Cars, especially in the past, tended to be much more forgiving of improvised DIY solutions.  However, in the case of my 1992 BMW K75S I quickly learned to use genuine OEM BMW parts and exacting German techniques as any other solution introduced new problems. 

Also, because there are so many cars on the road and so many DIY forums / videos people test and report the results to all kinds of unorthodox fixes and how long they last.  Our scooters are rarely messed with in these ways.  When I changed my head-gasket I couldn't find any instructions online and the manual left out important steps - like unbolting the motor and pushing it back to make room to get the head off!  Surprise!  In your case I would probably have used the silicone sealant rather than go online to order the part and wait forever for it to arrive and I would have had no idea that it could jam the starter. 

Great updates and please update when the gasket arrives.  Good work!
PaulC

maninbabylon

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Re: How do I set the timing on the Grandvista 250..?
« Reply #9 on: December 27, 2017, 12:24:26 AM »
So, I received the OEM crankcase cover gasket and it is installed and the starter is working perfectly now.  However, I have another problem. Now there is no spark from the spark plug. I have a new spark plug, and replaced it just incase I received a bad new one. It's happened to me before with NGK plugs. I also replaced the CDI and Ignition Coil, still nothing. It's turning over fine now, it just won't fire. Any suggestions would be welcomed.

maninbabylon

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Re: How do I set the timing on the Grandvista 250..?
« Reply #10 on: December 27, 2017, 06:11:51 PM »
Figured it out after reading this post http://www.kymcoforum.com/index.php?topic=25018.0
Who knew there was a kickstand kill switch...?  LOL

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