car no go-go

[dreamcatchu]

finally finished putting my new motor together and installed it, but the damm thing won't fire, before putting the motor in set everything up, even the dizzy, manually set the timing at 6 deg as per factory setting, primed everything and all i'm getting is a small carby backfire, i'm not game to keep cranking it as i installed a new cam as part of the build, i need help......

[Not_An_Abba_Fan]

Check to make sure you have set the timing correctly, not 180 degrees out. Take out number one spark plug, wind the engine 90 degrees backwards, put your finger over the spark plug hole and turn the engine forwards by hand to make sure you are on the compression stroke. You should feel the compression push your finger off. If you don't feel any compression you have the timing 180 out. There is another way to do it, but you need to take the rocker cover off.

[dreamcatchu]

timing is spot on, i set the cam, crank and dizzy all together, the only thing i can come up with at the moment is that the valves aren't closing completly due to the copious amounts of metal we took of the block ( 0.75mm ), but the motor is tight when turning over so that seems to rule that out

[Not_An_Abba_Fan]

A carby backfire indicates a timing issue. How old is the harmonic balancer? It hasn't spun on the rubber has it?

[DANNY8]

When we chucked a HC 173 head on the 202 in our SKiDWAGON, then started it she was backfiring through the carb. That turned out to be the rockers loose and after tightening it ran sweet.

http://www.youtube.com/watch?v=eUXeBMVmF4U

So maybe sumfin ain't working which is not opening the valves properly. If all the bolts are tight...then maybe it's low oil pressure and the lifters aren't pumping up enuf or sumfin.

[Tree cutter]

Sounds like the timing is 180 Deg out to me

[vlv8vic]

gas or petrol? certainly sounds like a timing issue or a collection of things.

[dreamcatchu]

turns out it was a timing issue, not enough sleep when putting a motor together aint good but all sorted now, just gotta sort out the carb