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Post by natedoggaz on Jul 13, 2013 2:08:18 GMT -5
157QMJ is stamped on the engine - unless I am looking for another number?
The Scooter model is Jonway YY150T-12 which is stamped on a plate on the front.
Thanks!
ND
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Post by natedoggaz on Jul 12, 2013 13:36:58 GMT -5
hmmm...
I am now wondering if it would be easier to just but a new engine. Would essentially have a new scoot...
Not to mention all the spare parts mentioned by Onewheel.
I have already spent about $50 on a new head, and I would be spending about that much on a new jug and piston. Not to mention all the work involved in tearing the old one down!
Does anyone know where I can get the best price on a new 150cc GY6 -- including the shipping? I live in Arizona.
Also, I am not sure if I need long or short - how can I tell this?
Thanks!
ND
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Post by natedoggaz on Jul 11, 2013 2:16:05 GMT -5
Alrighty...I am convinced... I am going to drop the engine and see if I can clean it out for possible metal shavings. I would hate to put on a new cylinder and head just to wreck them down the road.
The guy gave me all the receipts when I bought it. The engine was rebuilt less than 700 miles ago... who knows what the mechanic did to it... Possibly the oil pump went out or something too which wasn't replaced...
Has anyone done this before or can point me to a how-to guide to drop the engine?
It is a 2011 Jonway.
THANKS!
ND
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Post by natedoggaz on Jul 9, 2013 23:11:08 GMT -5
Hey all - thanks for all the comments and replies!
sorry I didn't respond sooner - was right around the 4th holiday...
So this is a 150cc scooter I bought off Craig's for pretty cheap.
I have not actually had the chance to ride it. When I took it home I realized the head gasket was leaking, so my rebuild began...
The original owner had the entire engine rebuilt prior to me buying it off him.
It may be because of the air intake for the reason the jug and piston are all jacked up. The seat apparently broke and he never fixed it and rode around on it for a while. With the airbox directly under the seat, he was actually sitting on it and broke it away from its supports. When the airbox broke away it cracked on each side and left holes from where it was supported.
When I changed the oil, I really did not notice many, if any metal shavings in the oil - but then again I didn't strain it to look for any...
Although the damage could actually be caused by my repeated attempts at starting it while I was trying to figure out the reason it would not start.
Its quite possible that I just need to replace the cylinder and piston. I will try looking into it a little more need see if I need to do a full teardown....
So far I have only purchased a new head, air filter, and some smaller parts. I would prefer to not have to buy a new engine if I can avoid it...
Thanks!
ND
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Post by natedoggaz on Jul 4, 2013 3:45:37 GMT -5
Cool thanks...not what I was hoping to hear.... but glad I looked... would have been a waste of time if I had not looked into the cylinder and piston and had at last thought there was an issue. Scrappy has the top end rebuild kit for $50 so I will just order for them again.
ND
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Post by natedoggaz on Jul 4, 2013 3:17:34 GMT -5
Hello All been a little while since I have been on here... It has been in the upper 110"s here in PHX and I just don't feel like wrenching in the heat.... Anyways, I got up the urge to install my new head I got from Scrappy... For whatever reason I felt like puling the cylinder off before installing the head just to be sure everything was OK. Here is what I found - do I need to replace the cylinder and head because of these gouges?? ![]() farm8.staticflickr.com/7367/9207491134_d062f6b8eb_z.jpg [/img]  Let me now what you guys think...If I need to replace that stuff, so be it. Would rather replace it now then having it break down on me later on. Thanks! ND |
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Post by natedoggaz on May 13, 2013 3:32:46 GMT -5
When I took the valve cover off the 2nd time (after the new gasket went in) I did notice that there was 1-2 small black pieces stuck on the inside. It looked kinda like ash so I pulled them out.
They were pretty small - so I don't think they caused any damage.
Does anyone know what I can use to clean those parts up?
Going to try 1 more time before I get a new head with a new gasket.
Thanks!
ND
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Post by natedoggaz on May 9, 2013 17:43:10 GMT -5
My new head gasket should arrive any day...
Now, what can I use or do to ensure I have clean and debris free surfaces so the gasket has no gaps and nothing can escape around it?
Also, can someone pleas provide the torque specs for the 6 bolts?
...and which I should tighten first (the 2 long side bolts or the 4 main head bolts...
Thanks!
ND
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Post by natedoggaz on May 6, 2013 15:58:49 GMT -5
Thanks for your input and advice onewheel and the rest!
It may ultimately come to purchasing a whole new cylinder and head kit...
I do want to try one more time though - although I will need a new head gasket first probably - URGH!
Does anyone have the torque specs for the head (the 4 in the middle and 2 on the side) and I will put it back together. Also the torque for the 2 exhaust bolts.
I did tighten it via the criss-cross method, so I don't think that I was responsible for warping it - if in fact it is warped. I will check it today with a straight edge and see if it is bent in any way.
Thank you!
ND
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Post by natedoggaz on May 5, 2013 17:44:43 GMT -5
Hello - Yes, I do have one..
One of the lower end 1/2" wrenches from HF.
It works, but not sure on its accuracy?
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Post by natedoggaz on May 5, 2013 17:33:11 GMT -5
Hello, Many of you have seen the issues I experienced in one of my past posts.. So I replaced the head gasket, and low and behold it "tried" to start. Sputtering, backfiring, and turning over ever so briefly. It did not want to take gas at times, and I was able to ride it about 100 yards until it stopped on me and I had to push it back to my house... Sometimes it ran for a few seconds, then it died and did not want to start again. I also replaced the exhaust gasket as seen below. I could hear and feel exhaust air coming from somewhere - like it was not all going through the pipe... Almost like there was a leak somewhere, but the 2 bolts were nice and tight into the head. I am starting to think that the head could be warped, but would like other opinions as to what may be going on here. I can feel and hear air escaping from somewhere around the gasket - but it is on very tight! Here is the gasket I am using:  Brand new head gasket - almost burned up!  Gasket totally warped!  Major exhaust/carbon buildup on the bottom of the head:  Burn marks all over the cylinder and on the lower left corner, as well as around the cylinder:  Burn marks and charring on the exhaust outlet:  It looks like it has been driven for 100's of miles instead of 100 yards. I have tried to start it quite a few times, but still a lot of wear. It was cleaned up to the best of my ability when I took it off the first time. Here was the "before" picture when I took it off the first time:  I made marks with a marker on the cam and timing chain before I took it off and put it back EXACTLY in the same spot. What is causing this? Is it a warped head - or something else?? Thanks! ND |
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Post by natedoggaz on May 1, 2013 2:11:15 GMT -5
It's the plastic petcock thing for vacuum only and it does have a line that connects to the charcoal canister.
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Post by natedoggaz on May 1, 2013 1:30:29 GMT -5
This is not for fuel - only vacuum lines are connected to it...
ND
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Post by natedoggaz on May 1, 2013 1:01:46 GMT -5
From this image from ScootDawg. It is the black plastic vacuum petcock in the upper left corner with 2 blue hoses attached. What is that? When I search for petcock, the only results I get are the one for fuel.  Thanks! ND |
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Post by natedoggaz on Apr 27, 2013 20:12:35 GMT -5
OK cool - I have a coupon for a digital caliper at HF for $10.99
I will measure the old gasket and the opening.
Wondering if I should use the measurements off the old gasket and base it to purchase the new one...
ND
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