Replacing cylinder body

[jayjmarlo]

I am replacing the cylinder body, I accidentally broke a stud on the intake manifold and broke the tip of the stud removal tool. It seemed cheaper to just replace the whole cylinder body than try and get it out. The one I ordered included the intake manifold and the piston and it was very cheep. So my question is what do I need to know to get this thing on? I feel like the piston attaches to something there are two holes on the bottom. I did a little research on the board and read about 2 pins? How do they attach? I pulled the head and am replacing the studs with stronger hardware. Also I ordered a copper gasket spray for the head gasket because it was recommended in the newbie guide. This is still a new kit. Any tips before I pull the base off? I see two bolts and than maybe I have to pull pins. I don't know how to get to them I'm sure I could just start taking things apart but as I'm waiting on parts in the mail I thought I'd ask before I break something again.

 

[Deleted member 12676]

I could assume you have a Grubee engine but you know what happens when one assumes. Please tell me which engine you have.

 

[jayjmarlo]

Ow sorry, I got it on Ebay actually it's not branded but it should be the same one. It's the 66cc model 2 stroke Chinese motor.

 

[Deleted member 12676]

Just take off the carb, exhaust pipe, and cylinder head. Pull the cylinder up and off.
Slide the new one down over the piston etc. Easiest way is to first take the piston off, insert it into the bottom of the cylinder, slide the cylinder/piston into place, and reconnect the piston. then push it all the way down and put the head and other stuff on.
Press the rings tight while inserting piston into cylinder. don't force anything. rings break fairly easily. Before getting frustrated and breaking anything take it to a mechanic.
Maybe you can find a video on youtube showing 2 stroke engine reassembly.
You're fixin' to find out why some people prefer electric motors. ha!

 

[BigBlue]

Here's a pictorial of an engine breakdown that might help you:
https://motoredbikes.com/media/albums/teardown-chinese-ht-49-80cc-engine.808/

Good Luck,

Chris
AKA: BigBlue

 

[BigBlue]

Here's another link that may help:
http://motorbicycling.com/showthread.php?t=297

Good Luck,

Chris
AKA: BigBlue

 

[jayjmarlo]

Thanks for the info. I got the cylinder off fine. My only concern is the lower gasket. It was stuck on the bottom side. So I pride it off. It looks ok, this is a new engine still. But it doesn't look great really it was suck on there pretty good like it had some adhesive on the bottom side. Should I use the copper coat gasket spray? I already ordered it because the newbie guide recommended using it to spray 2 coats on the head gasket. Should I do the same on the lower gasket?

 

[Deleted member 12676]

the head gasket has to deal with over 1000psi, whereas the base gasket only with 5psi max. Leave the base gasket stuck to the bottom. I would oil or grease it to make sure it don't try to also stick to the cylinder. If it isn't torn then don't worry about it leaking.

 

[jayjmarlo]

To clarify it was stuck to the base of the old cylinder. I peeled it off with a butter knife. It looks slightly ruffed up but it is not torn. You recommend I use it as is and just rub a little motor oil on both sides correct?