problem getting 350 started

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curse

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I got it running and it ran ok but I could not time it because the idle was too high. I checked for vacuum leaks etc but didn't find any. It sounded like it was popping out the carb and 1 time I hit the gas pedal and it dropped in rpms until I revved it up again, then the too high idle was back along with the popping. I'm leaning towards a sticky/gummed up distributor...thoughts?
 

AuroraGirl

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Uh.. I domt think the distributor can gum up.. unless im mistaken. If you have spark and its not misfiring, its probably working just fine. if its revving high, you got fuel and air getting in. Is your idle screw adjusted out? You didnt mention that. It sounds like your kickdown functioned when you said you hit it and it went down.. for starting you set the choke and it runs the rpms a little higher and then if you manually kick it down it goes to a slower idle with no choke closed.

Id check your idle screws.
 

curse

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Yes, idle screw is backed way out. Ya know what else I failed to mention?....It will not start now but is getting spark and fuel. it's not even spit-n-spuddering at all, Just turning over.
 

AuroraGirl

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The only way you dont get anything from "fuel and spark" would be no compression. I think you should check your spark with a grounded plug. an inline tester like said doesnt mean you got enough. And fuel... if you use starting fluid and something happens, it means you arent getting enough fuel to a point.
 

Bextreme04

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The mechanical weights can in fact gum up and not smoothly adjust as RPM increases. That shouldn't be the problem below 1200 rpm though. It could also be gummed up and stuck high, but again that isn't likely and should be pretty obvious when the cap is removed.

You should be adjusting the timing with the vacuum advance canister hose removed and plugged at the distributor. The engine should be fully warmed up and somewhere around 700 rpm. Your idle will change as you adjust the timing, so it might take some fiddling around to get the rpm and timing right. Just get it down below about 900 and then start moving the distributor around to get it close. Then adjust the idle and readjust the timing. You should be able to go back and forth enough to get it really close.

It would also probably be helpful once you get the timing dialed in to adjust the idle mixture screws and final dial in the idle rpm.
 

Bextreme04

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Put the idle mixture screws all the way in and then back out 2 turns. That will get you in the ball park and make sure that it should be at a spot that will allow it to start.
 

Bextreme04

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I would also recommend you get a TDC tool and verify that your timing mark on the cover is actually at the correct location and the damper hasn't started to fail. The outer ring on your damper could be slipping and the mark could be way off. This is the tool. https://www.speedwaymotors.com/Top-...k81iOXlMLAKVoEnZkaBQIrtOspSXavlhoC4zAQAvD_BwE

You basically screw it into the number 1 plug hole and then turn the motor over by hand until the piston contacts the stop. You then put a mark on the damper where it lines up with the timing mark. Then you turn the motor over the other direction until it again makes contact and stops against the tool and make another mark where the damper lines up with the timing mark. A spot halfway between those two marks is the actual mechanical TDC of the motor. If it doesn't remotely line up with the mark on your damper, you need a new damper because the rubber has degraded and the outer ring is slipping on the inner hub.

Once you have the correct TDC mark on your damper, make a mark on the base of your distributor where your #1 plug wire is located with the cap on. Then remove the cap and make sure the rotor is pointed directly at that mark when the mark on your damper is at the 0 deg timing mark.

Verifying the starting timing and then making sure the idle mixture screws are at the correct baseline turns should get it to at least start and run enough to fine tune.

The back fire and no start are symptoms of being WAY out on something. You either have a mechanical issue like valves out of adjustment/broken, or the timing is way off, or you have a massive vacuum leak. Maybe a combination of some or all of those things.
 

curse

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I can get it to start but it only runs with foot to the floor.
 

Bextreme04

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I can get it to start but it only runs with foot to the floor.

Like I said above, you've messed with a bunch of stuff trying to get it to start.

I would suggest go back to the beginning and methodically check it all mechanically to verify decent mechanical installation and close enough timing.

If you can get it to start but it needs lots of throttle to keep running and you don't want to be methodical, you can hook a vacuum gauge up to a main manifold source, start the engine and then move the distributor back and forth until your vacuum maxes out. That should help you get it close enough to run well enough to fine tune.

Having to floor it to get it to start suggests you could have crazy rich idle mixture as well. Again, screw them in until they softly bottom out and back off 2 turns. That will most likely be slightly rich, but still good enough to start easily and run decently. If they are more than 2 turns out, you probably had the idle mixture adjusted while there was a large vacuum leak.
 

Vbb199

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Finally got around to removing the mufflers
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I would've **** my pants. Then laughed and laughed and laughed for hours, Maybe days afterwards if that happened to me

I love it when stuff blows up :headbang::lol::laughing1:
 

Vbb199

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I think they sell a spark plug holder that plugs inline thats got a clamp on it, so you can do what you said with a little less work. I saw them at menards.

you can also hold the plug with the plug wire attached between your teeth, and roll the motor over.
 

curse

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Like I said above, you've messed with a bunch of stuff trying to get it to start.

I would suggest go back to the beginning and methodically check it all mechanically to verify decent mechanical installation and close enough timing.

I really appreciate everybody's advice and believe I'm checking it methodically. It seems like I set the timing "close enough"

1. The vacuum advance canister hose is unhooked and vacuum plug installed on carb.
2. I did turn the idle mixture screws all the way in lightly seated and then backed both out 2 full turns ( they were 1.5 turns out of the box. so far this is the only adjustment done to the new carb).
3. I went back through and checked all vacuum lines, checked pcv valve, and checked gaskets under the carb. Everything looks good.

Some of the recommendations above cannot be done yet since I can't get it running close enough to a decent idle to do it.

I ordered a tdc tool to verify the mark on balancer is correct. I was thinking just now that maybe the plugs are fouled from all of this.

So I guess my game plan is to check the harmonic balancer mark and check the plugs, maybe just replace them.

If I don't get it going soon I will have to pull some things apart and check mechanical items like valves. I know it might sound like it but this isn't my first time installing a distributor and setting timing. I've never had an issue and am stumped.
 

curse

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Having to floor it to get it to start suggests you could have crazy rich idle mixture as well. Again, screw them in until they softly bottom out and back off 2 turns.
Definitely rich! This is with the idle mixture screws 2 turns out. Waiting on the top dead center tool.
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