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300 6 cylinder not idling


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Good evening all,

I have a 1984 f150 with 300 6 with the duraspark conversion. I replaced the carb with a non feedback carb. The only way I can get it to run is to open the choke, and give it some gas while cranking. Once it goes I have to get the rpms up to stay running. At idle it misses badly and puffs through the carb, and dies.

Any help is greatly appreciated, also ask any questions you may have, and I'll do my best to answer

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Have you double checked firing order? What about distributor timing. If it keeps stalling I know setting timing is hard, if not impossible, but have you rechecked distributor at #1. Start with the basics, assuming you haven't already. Have someone look down the carb as you try and start it, is it flooding fuel into the intake? Be careful doing that one.
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Have you double checked firing order? What about distributor timing. If it keeps stalling I know setting timing is hard, if not impossible, but have you rechecked distributor at #1. Start with the basics, assuming you haven't already. Have someone look down the carb as you try and start it, is it flooding fuel into the intake? Be careful doing that one.

that is what i wa thinking.

i was going to get a compression tester, ( I want one anyway) and find tdc on number 1, and set with the timing marks.

As for looking into the carb, I'lldo that as soon as I have help.

Ill post results as soon as I can,

Thank you

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that is what i wa thinking.

i was going to get a compression tester, ( I want one anyway) and find tdc on number 1, and set with the timing marks.

As for looking into the carb, I'lldo that as soon as I have help.

Ill post results as soon as I can,

Thank you

If you did a DS2 swap, the straight six can and will start with the distributor timing 180* out. Or perhaps the dizzy is a tooth off?

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If you did a DS2 swap, the straight six can and will start with the distributor timing 180* out. Or perhaps the dizzy is a tooth off?

You don't need a compression tester to find TDC.

Pull #1 plug, ground the coil wire and using a starter button hold a finger over the plug hole and bump the starter till the air pushes your finger off the hole.

Then check to see if the timing marks line up. If it is off you should be able to turn the motor by hand.

Then check the firing order.

Dave ----

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You don't need a compression tester to find TDC.

Pull #1 plug, ground the coil wire and using a starter button hold a finger over the plug hole and bump the starter till the air pushes your finger off the hole.

Then check to see if the timing marks line up. If it is off you should be able to turn the motor by hand.

Then check the firing order.

Dave ----

Finally got time to on my project, got it all timed and idling well.

Turned it off and no start unless I adjust the distributor,.

I watch the vacuum advance and it doesn't move. So I have two questions

1. Is there a way to test the vacuum advance

2. Is the vacuum line to the vacuum advance supposed to have constant vacuum

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Finally got time to on my project, got it all timed and idling well.

Turned it off and no start unless I adjust the distributor,.

I watch the vacuum advance and it doesn't move. So I have two questions

1. Is there a way to test the vacuum advance

2. Is the vacuum line to the vacuum advance supposed to have constant vacuum

To test the vacuum advance, pull the hose off the carb and suck on it. With the distributor cap off you should see the plate inside turn as you apply vacuum.

As for constant vacuum to the vacuum advance, there are two schools of thought. I don't like to have vacuum at idle and then have it come in as you apply throttle. Others like vacuum all the time.

But on the 300 six with the Carter YF or YFA, there is frequently no port that gives full manifold vacuum, so you have to use the one they supply.

In any event, you shouldn't need vacuum advance to get it started. It sounds like your timing is late. I'd put it at least at 8 BTDC, if not 12.

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Finally got time to on my project, got it all timed and idling well.

Turned it off and no start unless I adjust the distributor,.

I watch the vacuum advance and it doesn't move. So I have two questions

1. Is there a way to test the vacuum advance

2. Is the vacuum line to the vacuum advance supposed to have constant vacuum

The stock configuration draws distributor advance vacuum from a carburetor port and has no suction to speak of at idle. If it runs well but won’t start without timing adjustment I might suspect the ignition module on the fender. It advances the spark during cranking for easier starting and if that is not happening it can cause problems.

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It advances the spark during cranking for easier starting and if that is not happening it can cause problems.

Ah, good info, I wondered what that white wire on the Duraspark did. I saw some diagram that implied it supplied power during cranking, but that didn't make sense since the red wire doesn't lose power during cranking, or at least I don't think it does.

 

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