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Old 11-01-2020, 06:03 PM   #51
forestb
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Re: Spark plug diagnosis

At 700 rpm I have 11 pounds of vacuum. In park
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Old 11-01-2020, 06:06 PM   #52
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Re: Spark plug diagnosis

Timing!
What’s your timing at 700 in park?
Just like it sits.
Vac gauge hooked up and vac hooked to distributor.
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Old 11-01-2020, 06:20 PM   #53
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Re: Spark plug diagnosis

15 degrees
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Old 11-01-2020, 06:31 PM   #54
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Re: Spark plug diagnosis

Plug off the distributor and tell me what your initial is?

And check your vac pot to see if it’s working. Pull a little vacuum on the hose with your lungs.
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Old 11-01-2020, 06:41 PM   #55
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Re: Spark plug diagnosis

Still 15
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Old 11-01-2020, 06:43 PM   #56
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Re: Spark plug diagnosis

So check your vac pot.
Do it while it’s running.
If it’s good your timing will increase.
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Old 11-01-2020, 06:44 PM   #57
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Re: Spark plug diagnosis

How do I do that? I don’t have a vacuum pump

Last edited by forestb; 11-01-2020 at 06:51 PM.
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Old 11-01-2020, 06:53 PM   #58
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Re: Spark plug diagnosis

Pull the hose off the carb.
Put a cap on that port.
Use your lungs and suck on the hose. The vac pot should move and your timing should increase or your idle rpm will increase.
Use a longer hose if you can’t reach.
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Old 11-01-2020, 07:16 PM   #59
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Re: Spark plug diagnosis

So I don’t have a longer hose and I can’t reach. I did attach my vacuum gauge to the port that you had me connect the vacuum advance to and it had zero vacuum. I attached the port that is directly above the driver side mixer screw (where my vacuum gauge was connected to) and then checked my timing and it read 33 degrees. So the vacuum advance is working when I apply vacuum from that port
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Old 11-01-2020, 07:30 PM   #60
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Re: Spark plug diagnosis

Yup!
Vac advance pot is good.
Leave it hooked up there and turn your idle down to 700 or lower.
See if your idle screw can be backed out enough not to make contact.
Try that.
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Old 11-01-2020, 07:35 PM   #61
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Re: Spark plug diagnosis

When I did this yesterday there was a point where my throttle cable prevented my throttle from moving as I unscrewed my throttle adjustment screw. I had to disconnect my throttle cable to lower it any further. Should I do that now
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Old 11-01-2020, 07:43 PM   #62
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Re: Spark plug diagnosis

I could get it down to around 400 rpm before it stalled. That is around the same time as it lost contact with the plate that it pushes on. I could pull on the throttle a little to lower it but that is when it stalled

Last edited by forestb; 11-01-2020 at 07:57 PM.
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Old 11-01-2020, 07:56 PM   #63
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Re: Spark plug diagnosis

Leave your cable hooked up.
Turn the idle down to 700 in park.
Adjust your mix screws.
See if you can close either mix screw without it quitting.
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Old 11-01-2020, 08:14 PM   #64
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Re: Spark plug diagnosis

So I tightened the drivers side mixture screw until fully tight and it kept running. When I listened it back up around 3 full turns the rpms dropped to around 400 and it almost stalled.
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Old 11-01-2020, 08:22 PM   #65
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Re: Spark plug diagnosis

Disconnect your throttle cable.
Turn the idle down. See if you can back the Idle screw out all the way.
The idea is to find a way to get your primary throttle closed enough to cover the transition slot and get your carb idling on the idle circuit and not the power circuit.
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Old 11-01-2020, 08:30 PM   #66
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Re: Spark plug diagnosis

I’m assuming you mean with the engine running. Won’t it just stall out again below 400 rpm? Or am I turning the screw down all the way without the engine running?
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Old 11-01-2020, 08:51 PM   #67
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Re: Spark plug diagnosis

You need to experiment.
Slowly turn the idle down while running.
You want to see if you can get the primary throttle almost closed.
Do you still have the vac advance hooked up in the same place on the port above the mix screw?

Speaking of mix screws just set them at 1 and 1/2 turns out.
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Old 11-01-2020, 09:00 PM   #68
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Re: Spark plug diagnosis

Yes that is where the advance is connected to. I might have to try this another day. I am loosing my light
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Old 11-01-2020, 09:20 PM   #69
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Re: Spark plug diagnosis

So I took my ds side screw to 1.5 turns out when I turned the ps screw down to nothing it stalled out. I turned it out to 1.5 turns out and was able to get it started again but it was barely idling and I had not even changed the idle screw. It is dark now and am done for the day. Any suggestions for next time?
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Old 11-01-2020, 09:43 PM   #70
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Re: Spark plug diagnosis

Idle screw action like that says you’re close on the throttle setting.
The transition slot is covered a bit.
For more idle you could first try 4 more degrees initial timing. If that helps the rpm adjust the mix screws again.
See if that helps.
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Old 11-01-2020, 09:43 PM   #71
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Re: Spark plug diagnosis

Thank you for all of your help today. I really do appreciate it
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Old 11-03-2020, 09:58 PM   #72
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Re: Spark plug diagnosis

So I think I got over the hump. I was able to unscrew the idle screw quite a bit using the idle screw and increasing the idle using the timing and mixture screws. I am going to try and get it a little lower and then try to dial everything in. What should I aim for as far as timing goes? The only reason I had time to work on it today was because my boss sent us home early today so that we could lock down the building just in case any protest started and so that we did not get road blocked in.
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Old 11-03-2020, 10:31 PM   #73
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Re: Spark plug diagnosis

Timing is best if it starts good hot and doesn’t ping while driving.
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Old 11-07-2020, 05:08 PM   #74
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Re: Spark plug diagnosis

I got the idle down as much as I think I can while bringing it back up using the mixture screws and the timing. Then set my idle to about 750 rpm in drive and around 1300 in park. I set my timing to around 23 degrees at both park and drive. I has a little bit of trouble starting when hot. I have not gotten a chance to drive it yet sense it is about to rain. When I adjust my mixture I am currently connecting the vacuum gauge to the port that the vacuum advance is usually attached to. Which means I have to disconnect my vacuum advance when doing this. Would it better if I connected the gauge to the lowest center port that is usually connected to the hole in the passenger side valve cover?
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Old 11-07-2020, 08:12 PM   #75
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Re: Spark plug diagnosis

It didn’t start raining so I was able to adjust things a little more. I set my timing To around 15 Degrees at 700 rpm and adjusted the mixture a little more with the gauge connected to the center port. It seems to start better. I will go for a drive tomorrow and see how it runs.
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