compression issues

[MrMoochie]

My crossfire 150 has around 100lbs of compression and it wont start. Im jus wonderin if thats enuff forit to run on. It has a new piston, rings and cylinder jug.

[x-bird]

if it's a completely fresh build, the rings may need to seat yet. I'm not sure how it is with these little things, but usually a car engine needs a fair amount of run time for this to occur and until then, there will be a slight amount of blow by, reducing compression a bit. While it sounds a little low, I'd think it wouldn't be the cause of a no-start situation.

[MrMoochie]

Thats what im not understanding because im getting spark and the carb is getting gas. I can usually figure this stuff out but im stumped. Thanx

[x-bird]

valve lash settings on spec? wondering if you can miss the timing marks on these to the point where you'd see a spark while cranking but have the intake valve closed so the spark is happening before the charge hits the chamber or after it's out the exhaust.

[MrMoochie]

Ill check that out because its kinda hard to set the timing jus right. Thanx

[x-bird]

thought about that after i posted and got the big duh moment. of course these will fire the plug when it's out for spark testing since the magnet passes the coil pickup. Gotta get off the V-8 mentality sometimes ... def check your timing since you did a full top end on it.

[BuggyMaster]

100lbs shuuld at least allow it to run. Im thinking timing.

[BuggyMaster]

And specifically cam timing.

[MrMoochie]

Ok guys so i finally got my gy150 to fire after redoing the timing. Now my issue is with the vacuum setup, there's hoses everywhere i cant figure it out. I need a link or some good detailed directions. Pleez help

[crossfire150(:]

http://www.google.com/imgres?hl=en&b...=LZEsRFF4oSfwi

*this is a helpful diagram for your 150 crossfire vacuum setup!