davep_96

Hey guys. Just finished hooking up my 355 that I just rebuilt and I'm having problems getting it to start so I can break it in. It only starts when I gold the pedal to the floor, and even then it dies very quickly. Keeps backfiring through the carb too. What am I doing wrong here? What does it mean when it shoots a flame out of the carb?

When I put the distributor in I left the timing alone so it was sparking at tdc. Then I rotated the cap counter clockwise just a little to see if it would stay started. All fuel lines are hooked up. Any help would be great. If you need any more info let me know. Thanks a lot

davep_96

Also, forgot to mention, my dad put the oil in the engine and I found out after that he didn't add the break in additive. We only ran the engine for a total of like 15 seconds. Would that have messed up the cam? I put the additive in today so when we try again tomorrow it's in there.

Stekman

When you built it and did the timing set, did you line up the gears dot to dot? If so, flip the dizzy 180° and restab.

davep_96

Yep gears were dot to dot. When I installed the dist I put my thumb over #1 spark plug hole and let it blow it off. Then aligned timing marks on balancer/cover. Then put dist in and lined it up to point at # 1 wire on cap, which was not pointing at #1 cylinder. ( I already had wires on cap and so the rotor did line up with the #1's terminal. Is it possible somehow #1 wasn't at tdc on the correct stroke?

Stekman

Dot to dot is #6 firing, #1 on the exhaust stroke. Both dots straight up, at the 10 o'clock position is #1 firing.

It's one of the most common errors when building small chevs.

davep_96

Well I got it started up. It was dot to dot but I put the dist in when #1 was tdc on compression stroke. Somehow the problem was that we were way too retarded, to the point where it took a lot of advancing just to see the timing mark on the guage. Not sure how we got that retarded cuz the dist started out really close to 0*. Runs good now, but I still want to know why it started so retarded.

Stekman

What cam/timing set did you use? New or used damper? Is this a non-computer controlled setup?

I've hooked up degree wheels to engines and found occasions where the marks are off by quite a bit.

If you're reusing a stock-style damper with the bonded elastomer ring, I have also seen instances where the outer ring slips in relation to the inner hub. This causes the timing mark on the outer hub to move relative to TDC.

davep_96

Comp cams 284h. Stock damper from a 89 pickup. So are you saying that the dots are off then? Cause if the damper is off from the cover guage, then when I set it at 10* it would not really be 10* then?

Stekman

Not saying that your particular instance is a case of the dots being off or not. I'm just saying it's a possibility, as I've spec'd it out before and seen it happen. Only way to know if that's the case or not for you would be to hook up a degree wheel and spec it out. Which, not really a plausible option since the motor is in the car and running.

Were it the damper situation, then yes, setting at x degrees of timing, per the timing indicator and the notch on the damper, would be incorrect. The outer hub is bonded to the inner hub at a specific place, locating the notch in a specific location in relation to the crankshaft keyway - and the rotating assembly. So say the outer hub shifted 10° counter-clockwise. Then you time the motor to 10° advance. You're really going to be at 20° advance.