Rebuilt a honda c50 engine valve timing is set and i have spark at the plug and can not get it to fire i also replaced the carbretor

SOURCE: ENGINE WONT TURN OVER

sounds like the timing belt it has a interference engine so if the timing belt broke you could have bent rods and cracked pistons or worse. good luck

SOURCE: engine not firing

this happened to me, only she was misfiring as opposed to not firing at all, i got the plugs and leads replaced (one needed a helicoil as the threads were worn) but chevrolet themselves did the job on it and told me the the camshaft was blocked with old oil, they flushed that and reflashed the ecu, and she was right as rain again

however it could be a timing problem? not too sure of timing procedures!

SOURCE: 2000 DODGE STRATUS 2.5 V6

There may be a ground wire that you forgot to put back or a power wire that give power to the coils. Re-check all electrical wiring and make sure they are all connected. Good luck and thanks for using FIX YA

SOURCE: GMC 2500 P/U 350 Vortec.. Installed rebuilt

Have you checked to see if your distributor is aligned properly? I just had to change out a distributor on a 1997 GMC 3/4 ton that has the V8 Vortec in it as well and you need to pay attention to the (2) numbers around the mating surface / rim of the distributor. You should see a number 8 and a number 6. You need to find TDC on your number 1 cyl. You can either slowly crank the motor over or turn the motor over with a ratchet and socket on the bolt securing the main pully to the crank while another person places their finger over the spark plug hole and when it just starts to Stop pushing air out past your finger then stop. Is the rotor aligned with the number what ever size engine you have in your truck (i.e. 6 or 8)? If not then your timing is off. You will need to remove the distributor and rotor, then install your rotor (before re-installing the distributor) and align the rotor pointer with either the number 8 or 6 stamped on the lip of the distributor where the cap sits down and creates the seal. I have found that they run both numbers on the distributor because they use the same distributor in both the V6 and V8 Vortec motors or a least the plastic base of the distributor. There will be (2) numbers here and sometimes hard to see. Align the pointer with what size engine you have and lower the distributor down into the hole. If the end of the shaft starts to turn the rotor as it aligns with the oil pump causing the pointer to no longer be pointed at the number that indicates which engine this is being installed in then you need to remove the distributor and look down into the hole where the distributor goes in and you'll see the end of the oil pump shaft with a slot (perfect for a big flat head screwdriver) staring back up at you. You'll need to insert a long shanked large flat head screwdriver down into the hole and turn the slotted oil pump shaft until you can successfully lower the distrubutor into place and not lose your mark. I also found that you'll need to have to pointer of the rotor a bit retarted from where it is suppose to be. This is because the distributor shaft gear is swirled and will cause the rotor to turn as it finds its mark, aligns and lowers down into a seated position. When it is seated and the rotor has stopped turning it should be pointing at the indicated cylinder Stamp in the lip that is your size motor (V6 or V8). Now it should be on time. The computer will take care of advancing and retarding.

If not the timing, then I would also consider that you may have a bad crank shaft sensor. These are merley suggestions because there is no more to go on than what you've submitted.

SOURCE: 2007 Pt Cruiser I Changed

I'm going to give this some thought and try to get back with you tomorrow....a cousin back home in Missouri is a MoPar nut and an excellent mechanic in his own right.