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Timing for dummies, can't get motor to start!

8_YOUR_H2

8_YOUR_H2

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I can not get my new motor to fire for the life of me. It will turn over for a few seconds then a huge sonic boom comes out the tail pipes then nothing. All of the plug wires are correct and there is spark. Plugs gapped at .045 just like they are supposed to be.

When I set the motor at TDC I watched when the intake valve opened then closed. As both valves were closed I lined up the timing mark with the pointer. Shouldn't that be #1 TDC? What am I doing wrong? Everyone around here says it is 180* out. So that would be one full revolution of the motor after my inital setting.

This whole thing is going to end up on the camp fire.
 
take the coil wire off,take the plug out of the #1 cylinder.Hold your finger over the hole and have someone bump the engine over until you feel the air rushing out of the hole.then set the balancer on tdc and that should give you tdc on #1 cylinder.then just stab the dist. in and line up the rotor with the #1 terminal on the cap.
 
8_YOUR_H2 said:
When I set the motor at TDC I watched when the intake valve opened then closed. As both valves were closed I lined up the timing mark with the pointer. Shouldn't that be #1 TDC? What am I doing wrong? Everyone around here says it is 180* out. So that would be one full revolution of the motor after my inital setting..
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you would be correct. whoever is advising you otherwise is wrong.

sound slike you need to advance the timing a little (that is turn it clockwise, to make it spark sooner.) it sounds as if its sparking too late, causing the pop out the tailpipe.
 
If you've got a timing light, it's pretty easy to make sure you are darn near 0* at least. Of course make sure you are TDC #1, then hook up the timing light to the #1 plug wire. Turn key to "run", rotate distributor back and forth until the timing light fires. Where it fires is 0*.

You can always just turn the distributor as someone cranks the engine, but on a new build I'd rather fire it up right away than let it sit there with the starter grinding away.
 
dyeager535 said:
You can always just turn the distributor as someone cranks the engine, but on a new build I'd rather fire it up right away than let it sit there with the starter grinding away.
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Especially with a new flat-tappet (non-roller) cam in the new engine. I like to fire right up and get the revs up a little ASAP, but maybe that's just me.
 
Did you adjust the hydraulic lifters (if you have them)? If so, they could be too tight. I experienced this. If they are adjusted too tight, you won't get any compression cause the valves don't seal completely and then you get the firing through the carb and exhaust.
 
also, did you prime the oil pump? your lifters may be collapsing, and not alowing the valves to open, thus the engine wont run then.
 
We primed the oil pump but not for a real long time. I did soak the lifters in oil for a few days before I put them in. When I took off the valve cover I could see the valves opening and closing as I turned the motor over. I will back off the rocker nuts a bit cause I know I may have gone a little too tight on them.

I worked on it a bit today and nothing. No sonic boom, not even a hiccup.
 
81K5GUY said:
take the coil wire off,take the plug out of the #1 cylinder.Hold your finger over the hole and have someone bump the engine over until you feel the air rushing out of the hole.then set the balancer on tdc and that should give you tdc on #1 cylinder.then just stab the dist. in and line up the rotor with the #1 terminal on the cap.
Click to expand...

You would be right if we only had 2 strokes to the combustion cycle, however you may want to be alittle more precise than that. The "air rushes" out the hole on two of the strokes.
 
Wouldn't the air come out of the spark plug hole on the compression stroke only when both valves are closed?

Are the 4 cycles...

1. Intake
2. Compression
TDC
3. Power
4. Exhaust

Not trying to be a dick, just trying to make sure I am not an total moron.
 
Or, suck, squeeze, bang, blow.

Yes, there is only one stroke where if everything is working correctly, you get the compression mentioned in the 4 cycle engine. I suspect Mudzer just spaced his reply, which is why I was chuckling.
 
Mudzer said:
You would be right if we only had 2 strokes to the combustion cycle, however you may want to be alittle more precise than that. The "air rushes" out the hole on two of the strokes.
Click to expand...


sorry I should have been more specific,Im not always good at putting my thoughts into words lol.
 
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