|
|
Post by dickyh on Oct 1, 2015 21:57:58 GMT -5
I used the flange style and the exhaust is very tight
|
|
|
|
Post by dickyh on Oct 1, 2015 18:50:30 GMT -5
OK, So what I thought was sound transferring from the head bolts is not it at all, and now I'm worried! I've attached a vid of the engine running and the noise it is making. It is as if something is loose and the noise is coming from underneath the engine. I thought it may be a roller rattling and checked but not the case. The scooter is running perfectly but the noise is got me worried. here's a thought... when i put the new head on, as I was setting the piston to TDC, the chain came off the sprocket inside the case. I was able to get it back on, and put everything else back together. The chain guides are in place and everything is running fine. was there are piece that may have fallen out and is rattling on the bottom? I have no clue! Anyone have an idea??? |
|
|
|
Post by dickyh on Sept 30, 2015 16:50:48 GMT -5
dickyh... That's great news!! It's awesome when we get another scooter back on the road. I hope the experience doesn't make you hesitant on doing mechanical work. Everyone here have made mistakes, and had to fix them. That's part of what makes scooters so fun. Replacement parts are very cheap. Thanks! Since I've had this scoot, I have done all of the mechanical works on it, so this was just more experience, however it was a bit intimidating, but now more confident than ever. One final issue I encountered that for some reason, I guess the new parts were a little shorter, is that the valve cover wouldn't fit over the bolts. I was determined not to let it stop me and I carefully covered everything, so not to allow any shavings in and literally cut off the top of the bolts as a temp fix and ordered shorter bolts to replace them with, which I will do on Saturday. And for some reason the scooter is a lot quieter than it ever has ever been, even before I set the gaps too large. One issue is that at idle there is some chattering coming from the valve cover, but it doesn't seem to affect the performance what so ever and about 2400 rpms it goes away. It is not from the tappets being too loose, cause I quadruple checked them and they are both at .004. and it is not the normal sound of tappets being too loose. I think because the bolts are longer than they were that the sound is transferring up them to the valve cover. If anyone has any other input on this PLEASE let me know. But the scoot has never run better. |
|
|
|
Post by dickyh on Sept 30, 2015 5:12:16 GMT -5
Well, the engine is finally back together and the scoot runs like a top. Thanks to ALL who helped me through it all. Glad to know there are people out there willing to help.
|
|
|
|
Post by dickyh on Sept 27, 2015 6:30:22 GMT -5
From the guide I read, it says 8lb on the 2 that hold the head to the cylinder and 13lb on the 4 long ones. I did in a cross-cross pattern as instructed and I was being very careful only a little at a time. BTW, I stopped on the side ones cause I was sure that if I kept going I was going to snap them off.
The wrench is supposed to click when it is at the right setting, correct?
So now my question is do I really need to torque them? I usually have a pretty good feel on tightness. The thing I don't like about the torque wrench is that you can't really feel how tight they are getting. I borrowed it from a race car mechanic, so I assumed it was working properly, and triple checked the setting.
The other question I have is if I remove the rocker assembly, I could probably switch out the broken stud, as it snapped right at the top. I really don't want to take it all the way down if I don't have to. getting the piston in the cylinder took a lot of work as I didn't want to mess up the rings or the cylinder, so I was being very careful and not forcing anything. And I don't have another set of gaskets.
|
|
|
|
Post by dickyh on Sept 26, 2015 17:47:57 GMT -5
Well, broke a stud... I used a torque wrench at 13lbs foot as recommended by someone and one of the studs snapped, so now I have to wait till tuesday to try again. Positive side I guess is I'm learning about the engine anyway, LOL I ordered 4 and going to replace them all in case I stressed the other 3 studs. so close...  thought I was doing the right thing by using a torque wrench, but now I'm afraid to try it again for fear off snapping the new studs when I get them. |
|
|
|
Post by dickyh on Sept 26, 2015 9:21:29 GMT -5
Funny you should say that cause I change the oil like every 300 miles RELIGIOUSLY and I installed an oil cooler about 3 months ago.
OK so I'm having some difficulty getting the cylinder over the piston. goes up to the point where all the rings are in the cylinder and wont go any further and I don't want to apply too much pressure. any suggestions???
UPDATE: GOT IT ON
|
|
|
|
Post by dickyh on Sept 26, 2015 7:23:26 GMT -5
So my cylinder and piston came today - Whoo Hoo! and I have a few questions... Firstly the ring order for the top two. both are black but one appears to have a slight bevel to it and has marking on it (R) the other is all black and has a marking (RN) which it the utmost top? I'm guessing the one marked r with the slight bevel. the second question is, is there anything I need to do to prep the piston or the cylinder, like clean it out or something? I know on install to coat both with a light film of oil, from what I've seen and read anyway. Anything else I should know? I also know to check the ring gap inside the cylinder before attaching to the piston. Markings on the top two ring will be installed up. Can you take a pic of those rings? Since you have two different rings there this is critical you get this right. Is the Bevel to the inside or outside of the ring? Is there any undercuts on the inside of either ring? doesn't even surprise me anymore of a Chinese mfg supplying product with no instructions. And actually the vendor who puts there name on the product should step up. I found out that the R with the bevel on the outside of the ring is the top most ring and when I checked the gaps it made sense as the top is .008 and the bottom is .012 which is correct according to the calculations I did based on instruction I read |
|
|
|
Post by dickyh on Sept 25, 2015 17:07:53 GMT -5
So my cylinder and piston came today - Whoo Hoo! and I have a few questions...
Firstly the ring order for the top two. both are black but one appears to have a slight bevel to it and has marking on it (R) the other is all black and has a marking (RN) which it the utmost top? I'm guessing the one marked r with the slight bevel.
the second question is, is there anything I need to do to prep the piston or the cylinder, like clean it out or something? I know on install to coat both with a light film of oil, from what I've seen and read anyway. Anything else I should know? I also know to check the ring gap inside the cylinder before attaching to the piston.
|
|
|
|
Post by dickyh on Sept 25, 2015 17:00:35 GMT -5
Here's a weird question... As I stated I received to heads yesterday with everything installed, both had the spark plug in and both heads that the coil wire goes over seemed to be purposely bent. Is there a reason for this? Not sure what you mean, can you take a pic? here's a pic of what I mean. Note that I am going to use my own plug the nch7 ( i think that's what its called) but was wondering if there is a purpose for doing this as I have never seen it done before  |
|
|
|
Post by dickyh on Sept 25, 2015 6:30:01 GMT -5
Here's a weird question... As I stated I received to heads yesterday with everything installed, both had the spark plug in and both heads that the coil wire goes over seemed to be purposely bent. Is there a reason for this?
|
|
|
|
Post by dickyh on Sept 25, 2015 6:26:25 GMT -5
remember where all the little metal guides go. It's important to reinstall how it was. You'll see what I mean when you tear it down. Make sure to install the rings properly and to use a torque wrench to tighten it up in the end. Pretty much same exact procedure as this: www.49ccscoot.com/bbk.htmlThanks for the info. answered a lot of my questions about procedure! |
|
|
|
Post by dickyh on Sept 25, 2015 6:25:10 GMT -5
Piston guy. Pretty sure it was the exhaust valve. If it was the intake valve, then nothing was likely damaged. I read it as the exhaust valve. I just read it again, and it was the exhaust valve lash that he set far too large. Just checked his new thread. The exhaust valve blew the seal, and was stuck open. I set both large, but I am pretty sure it was the exhaust valve that caused the problem because as I stated earlier, when I took the head off the collar clips for the exhaust valve pretty much came off in my hands. |
|
|
|
Post by dickyh on Sept 25, 2015 5:06:39 GMT -5
thanks! was able to get them loose with a little effort. did you replace your cam and if so where, which one ? for future reference if I ever need to get one... No problem.
I never was able to find a cam. We resorted to using the old cam. One of the lobes was damaged, but it looked like the rocker did not ride over the damaged area so we reinstalled and crossed the fingers. He has a few hundred miles on it now and it is still running fine.
I've looked high and low and can't believe that there is not a replacement out there somewhere. Scrappy doesn't even sell on for the head they sell. Maybe someone knows how to convert to the common style? Mine is fine, thankfully and I hope i won't ever have to replace it, but sure would like to know where, what to do if the need ever arises. |
|
|
|
Post by dickyh on Sept 24, 2015 20:56:28 GMT -5
Ever tried GY6 store... I got clutch from them. Free shipping and was quick, but never bought anything expensive. They do have gy6b stuff. Taida too!! Thanks, I'll look into it. |
|
