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Old 10-18-2017, 01:52 PM   #31
Bob123456789   Bob123456789 is offline
 
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Thank you sir.


I will try the ATF in the cylinder hole followed by a compression test.


Could you elaborate more what you mean by check the timing. Right now everything is together engine and all the body panels. If you mean check the marks on the camshaft sprocket (see page 10 of the following document) that is a fair amount of work and I would like to make sure we check the other things first before diving in to it. I can easily check the second set of marks on the shaft that drives the CVT (see page 11 of the following document).


http://www.chinesescooterreference.c...Adjustment.pdf


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Old 10-18-2017, 06:43 PM   #32
Bob123456789   Bob123456789 is offline
 
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Just did the compression test again. Here are the results:


60 psi dry
60 psi after putting ATF in the cylinder before the compression test


 
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Old 10-19-2017, 07:05 AM   #33
bogieboy   bogieboy is online now
 
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looks like a tear down is in order.... something went wrong, and its really hard to guess at what it is without pulling things apart.... start with timing, like the whole document you posted, start fresh, then if that checks out, time for the head to come off to check the rings and head gasket.


 
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Old 10-19-2017, 09:39 AM   #34
Bob123456789   Bob123456789 is offline
 
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Thanks bogieboy.


A couple of questions. First is it worth redoing the valve adjustment before pulling it apart? I can do the valve adjustment and be at top dead center by putting something in the cylinder and checking the marks on page 11 of this document. I can't see the parks on page 10 of the document without pulling it apart.


http://www.chinesescooterreference.c...Adjustment.pdf


Does the fact that the compression is the same dry and with ATF tell us something?


Is there anything else I can try before I pull it apart?


 
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Old 10-19-2017, 09:49 AM   #35
Merlin   Merlin is offline
 
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Question

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Originally Posted by Bob123456789 View Post
Thanks bogieboy.


A couple of questions. First is it worth redoing the valve adjustment before pulling it apart? I can do the valve adjustment and be at top dead center by putting something in the cylinder and checking the marks on page 11 of this document. I can't see the parks on page 10 of the document without pulling it apart.


http://www.chinesescooterreference.c...Adjustment.pdf


Does the fact that the compression is the same dry and with ATF tell us something?


Is there anything else I can try before I pull it apart?
I would redo the valve adjustment. Just make sure your at top dead center. It sounds to me like you might be 180 off.
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Old 10-19-2017, 10:54 AM   #36
Weldangrind   Weldangrind is offline
 
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Bob, I recommend that you repeat the compression test with the valve cover removed.
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Old 10-19-2017, 11:17 AM   #37
Bob123456789   Bob123456789 is offline
 
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We are going to get this thing going soon! Thanks for everyone's help.


bogieboy do you agree that I should try a valve adjustment before taking everything apart again? Is there anything else I should do before doing that?


WeldanGrind why do you recommend doing the compression test with the valve covers off? Intake, exhaust or both?


 
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Old 10-19-2017, 11:53 AM   #38
bogieboy   bogieboy is online now
 
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My guess for WAGs suggestion is to see if you hear chuffing, that would be indicative of a blown headgasket. It cant hurt to do another valve adjustment either, i have had strange things happen on brand new tractors...LOL had one engine that had a valve adjuster back out of a rocker arm in 4 hrs run time, straight from the factory.... you may have a similar issue.... or it just backed out enough to cause low compression ...


 
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Old 10-24-2017, 11:10 AM   #39
Weldangrind   Weldangrind is offline
 
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Bob, I meant the entire valve cover. If the compression returns by simply removing the cover, my guess is that it was on backwards.
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Old 12-01-2017, 03:33 PM   #40
Bob123456789   Bob123456789 is offline
 
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Life got in the way of getting this thing going which I want so much soon. Thanks so much to everyone who has helped with that.

First I reset the intake valve gap then did a compression test since I could do that without removing a bunch of panels. 45 psi very low.I reset the exhaust valve gap to 0.20 mm and did a compression test.Compression was still only 45 psi.

What do I need to do next to get this thing going? I had fuel and spark but no compression. What else could be causing the low compression?Timing chain off by one tooth (this engine has two sets of marks, one on the timing chain sprocket and another on the engine main shaft and both are set right at the same time)?

Any ideas?


 
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