First time engine build won't fire

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BOXHEADgumby

BOXHEADgumby

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I have a 360 i rebuilt it is my first time and I took my time doing it to avoid mistakes but I am beginning to feel like I've missed something. I have the motor in the car now a 74 duster, and for the life of me it will not fire. I found that i had the distributer drive gear clocked in wrong i have since fixed that and I've checked my wires again and again and it still will not fire. I am getting spark and fuel in fact it is spitting gas back out the carb. Any suggestions ?
 
BOXHEADgumby said:
I have a 360 i rebuilt it is my first time and I took my time doing it to avoid mistakes but I am beginning to feel like I've missed something. I have the motor in the car now a 74 duster, and for the life of me it will not fire. I found that i had the distributer drive gear clocked in wrong i have since fixed that and I've checked my wires again and again and it still will not fire. I am getting spark and fuel in fact it is spitting gas back out the carb. Any suggestions ?
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have you checked to make sure you have the timing on the correct stroke?
 
BOXHEADgumby said:
I have a 360 i rebuilt it is my first time and I took my time doing it to avoid mistakes but I am beginning to feel like I've missed something. I have the motor in the car now a 74 duster, and for the life of me it will not fire. I found that i had the distributer drive gear clocked in wrong i have since fixed that and I've checked my wires again and again and it still will not fire. I am getting spark and fuel in fact it is spitting gas back out the carb. Any suggestions ?
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If it's not some kind of roller cam stop cranking on it until you are sure it will fire. If it's a flat tapper cam you'll kill it if you don't get it fired.
 
yellow rose said:
If it's not some kind of roller cam stop cranking on it until you are sure it will fire. If it's a flat tapper cam you'll kill it if you don't get it fired.
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Good to know thanks, y'all don't think maybe my carb is the issue by chance ?
 
BOXHEADgumby said:
I did however it's worth trying again.
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yeah, double check, i made this mistake when i was 19 and trying to put together my 360 based stroker build. I screwed up and had it on the exhaust stroke instead of the compression stroke. after 2 hours of trying, my grandfather walked out, took one look, and knew exactly what i'd done. fired up right after that.
 
How to set your timing.

1...Remove no1 plug, stick your finger in the hole and bump the engine until you feel compression on your finger

2...Wrench the engine CW from that point until you get the timing marks set on about 10-15 BTC. Don't allow the marks to go past and "around once" from step one

3....Pull the cap and see where the rotor is. It should be APPROACHING the tower contact for no1. Position of the distributor or drive gear DOES NOT MATTER. All that matters is that the rotor is coming to wherever the no1 wire is plugged into the cap

4......If you have a magnetic dist. set the dist housing so the reluctor is about centered in the magnet. YOU CAN CHECK timing on the starter with a light, but don't crank forever. Two people works better. Once you get good at this (magnetic) you can actually hear or rig a gap and see the spark. With the dist loose, retard (CW, SB) the timing some, and then move the dist advanced (CCW, SB) until the spark "triggers." By moving the dist CW, then CCW, to the point of "snap," and being more careful each time, you can get the timing close enough to run

5.....Since you are having trouble, might be wise to check that you actually have a nice hot spark. Ground a screwdriver with a clip lead, and hold it right at the top of the coil tower or "rig" a test gap or plug to the coil tower. Crank the engine USING THE KEY. With a solid core coil wire or the grounded screwdriver, you should get a hot, fat spark at least 3/8" long and typically 1/2" long
 
yellow rose said:
If it's not some kind of roller cam stop cranking on it until you are sure it will fire. If it's a flat tapper cam you'll kill it if you don't get it fired.
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Put in some oil through the breather and it will drip down on the cam to keep it lubricated...

Maybe throw in some STP or Motor Honey...
 
Turn the distributor counter clock wise a bunch and then try it, if all else is right... could just be retarded.
 
BOXHEADgumby said:
I have a 360 i rebuilt it is my first time and I took my time doing it to avoid mistakes but I am beginning to feel like I've missed something. I have the motor in the car now a 74 duster, and for the life of me it will not fire. I found that i had the distributer drive gear clocked in wrong i have since fixed that and I've checked my wires again and again and it still will not fire. I am getting spark and fuel in fact it is spitting gas back out the carb. Any suggestions ?
Click to expand...

Follow the instructions from 67Dart273 (Del) ...

If you have a good spark, set the initial timing to 10° like Del has described above...

If the carb is still dry and won't squirt gas when you cycle the accelerator, then get a jar and pour a little gas down the carb while holding the throttle blades open, then close the throttle and try to start it... If it doesn't start, then pour a little more gas down and try again until the carb is "primed" and you can get gas to squirt...

As long as you have gas, spark, and the timing chain is correctly installed, you should be able to get her to start...

Set the initial timing to 10° - 15° BTDC or where you can get to run steady, play around with turning the distributor - set it to where you begin get the max vacuum and leave it there until the engine reaches temp...

Once started, then set the timing to 34° - 36° BTDC at 2000 - 2500 RPM once it is warm...

Then let it run for 45 minutes to break in the cam, making sure to watch the oil pressure and water temp... Check water temp about every 5 - 10 mionutes while breaking in the cam to be sure you don't overheat... If it starts overheating, shut it down or get a garden hose and run it over the radiator to get the temp back down...
 
MOPAROFFICIAL said:
Turn the distributor counter clock wise a bunch and then try it, if all else is right... could just be retarded.
Click to expand...

Turning it too much one way or the other can get you where it won't start...

I prefer to find TDC, then set the engine to 10° BTDC and crank it up.... I've had good luck getting fresh engines to fire at 10°....

Then adjust the initial timing to max vacuum and try to get it to idle as smoothly as you can...

Then set total timing at 2000 - 2500 RPM after the engine reaches running temp (160° - 180° F)...
 
krazykuda said:
Turning it too much one way or the other can get you where it won't start...

I prefer to find TDC, then set the engine to 10° BTDC and crank it up.... I've had good luck getting fresh engines to fire at 10°....

Then adjust the initial timing to max vacuum and try to get it to idle as smoothly as you can...

Then set total timing at 2000 - 2500 RPM after the engine reaches running temp (160° - 180° F)...
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That's kind of been my worry is that i did in fact not install the timing chain right.
 
whats your firing order? Look at distributor: 18436572 CW. Top of compression in driver front (#1) pulled plug should be pointing to or very close to #1 on tower which could be anywhere. Easy to wire backwards if you grew up on B/RB's. Also, look at the crank snout (under the bolt and washer) for the keyway. Its almost always at 1:00 when at TDC. Something you can check without taking the timing cover off. I have started a motor with a propane torch head stuck in the open throttle of a carb with no gas in it, an option if you think your carb is SNAFU. I think Mopar did that when setting the distributors along with a damper probe.
 
BOXHEADgumby said:
That's kind of been my worry is that i did in fact not install the timing chain right.
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If you're not sure, you may want to pull the timing chain cover to verify that it's correct... A tooth off can make a difference...
 
If you pour gas into the venturies;FIRST,move the car outside, away from any valuables.
Then;you better have a fire extinguisher nearby,and if you see flames, use it!!
I don't like that idea at all for a newbe.

Start with a properly filled carb, then follow post #8.
Once it's running post #12, has it covered.

I just gotta add, that it sorta sounds like the intake valves are not sealing. Normally I would suggest a compression test, but with the break-in lube being cast off the cam with the already excessive cranking, I'm not so sure at this time,that it's a good idea. .
So if you just can't get it going with the above helps, Then, do a compression test. It may be that your valves are not closing. But it's too early to go there, just yet.
 
BOXHEADgumby said:
That's kind of been my worry is that i did in fact not install the timing chain right.
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What cam do you have? You can get "some idea" of whether it's right by doing a quick "degree check"

Pull the driver's valve cover so you can watch the no1 valves, review the timing events, and see if you can justify valve movements to the balancer. If you pick events closer to TDC, you can estimate quickly, IE measure the distance from TDC to 10, and from 10 retard to 10 advanced on the tab. "Mark" this distance on the balancer using masking tape, whatever you can come up with.

For stock cams, there is a procedure in some of the factory service manuals. You can download these free from MyMopar.com

As the advice above, do NOT go cranking and cranking on that new cam. A new engine fire should NOT be more than seconds of cranking to get a poop, a stutter, a "start and die" and then run.
 
AJ/FormS said:
If you pour gas into the venturies;FIRST,move the car outside, away from any valuables.
Then;you better have a fire extinguisher nearby,and if you see flames, use it!!
I don't like that idea at all for a newbe.

Start with a properly filled carb, then follow post #8.
Once it's running post #12, has it covered.

I just gotta add, that it sorta sounds like the intake valves are not sealing. Normally I would suggest a compression test, but with the break-in lube being cast off the cam with the already excessive cranking, I'm not so sure at this time,that it's a good idea. .
So if you just can't get it going with the above helps, Then, do a compression test. It may be that your valves are not closing. But it's too early to go there, just yet.
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My feeling also. Adjustable valve train? Does it sound like it has compression or does it spin real fast.
 
The gas spitting back out of the carb indicates that the ignition timing is way out of time, OR you have the rotor in the distributor indexed wrong. And if the cam timing is off, then setting ignition timing to the damper mark will be wrong. As said, if the timing is right and there is a bit of fuel in the engine, it will fire.

- Check spark as in port 8. Checking for the spark to jump a spark plug gap in open air is not a valid test at all. The spark has to jump at least 1/4" in open air to be able to jump a spark plug gap in a compressed fuel-air mixture.
- Pull the distributor cap with the damper at 0 TDC; the rotor should be pointing directly at, or slightly CCW from, the #1 or #6 spark tower.
- Pull the valve cover as described in post 18 and look at the valves. When the timing mark on the damper passes 0 on the timing cover, on either #1 or #6, the exhaust valve should be closing and the intake opening. On the next rotation of the damper mark past the 0 mark, the other of these 2 cylinder's valves should do this. If this exhaust close/ intake open does ot happen right around the 0 mark, then the cam timing is off.
 
STOP CRANKING!!
Have someone there that knows this stuff come and give a quick hand.
 
j par said:
STOP CRANKING!!
Have someone there that knows this stuff come and give a quick hand.
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Luckily I don't think it's been cranked on as much as it seems hopefully at least. I tried it initially and got gas sputter back at me and no attempt to fire thats when I stopped and knew it was a timing issue realized it had the drive gear in wrong and fixed that for ease of keeping track of wires and such. I then made sure I have a spark by grounding a plug. I did notice mention of intake valves and I did put on adustable rockers and makes me wonder if when I set the lash if I wasn't 180 out and that's why it's given me so much trouble, if I get the chance I'll double check that before cranking it again as well as going through the steps listed above and keep myself in check. I'll let y'all know if I get anywhere and really appreciate the help and yes if it doesn't work this time I will get someone over here to help me out.
 
What are you doing to get on the compression stroke?

I don't set valves with a chart, I use EOIC which means......

Bump the engine until the EXHAUST just OPENS and set that intake

Bump the engine until the INTAKE opens and nearly goes CLOSED and adjust that exhaust

===========================

There are two ways to get on the compression stroke. Pull no1 plug, stick your finger in, and bump the engine until compression blows your finger out. Stop!! Look for the timing marks which should be "coming up." Then wrench the engine until the marks are "where you want" timing.

Second method has a caveat. If you have either valve cover off, rotate engine to TDC and look at either no1 or no6 valves. One set will be both closed, the other set will be both some open, on "split overlap." The two that are closed are compression stroke

The caveat is this is easy to mistake. When you get "let's say" looking at no1, on TDC, and you think they are closed, wrench the engine say, 20 degrees each way from TDC. If the valves move, they are split overlap. If they do not move you are on compression stroke
 
BOXHEADgumby said:
I then made sure I have a spark by grounding a plug.
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What does this mean? If it means that you take out a plug and then ground it and watch for the spark to jump the plug's gap, that is NOT a good test of spark. A spark that jumps a .035" to .045" gap in open air is in no way guaranteed to jump that same gap in a compressed fuel-air mixture. If it won't jump AT LEAST a 1/4" gap in open air, then the spark is not good enough. You have to test the spark right before you can rule it out as a problem.
 
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