Vibration at idle..

[78futura]

Ok 78 futura 302. 10k into engine. Started a crazy shake the column at idle about a year ago.. duraspark 2 factory. New plugs wires cap rotor 2 years ago. Checked everything and found ok. Took the pickup coil out of the distributor. The outer part with the windings sits very loose on the inner steel section. When I ohm it out at the plug and wiggle the winding part ohms go from 400-600 sometimes 1.6k and even 0 ohms.. Are all these coils made that way? I am thinking to replace the pickup coil as it may be sending screwy signals to the module and making the idle uneven.. any thoughts?
I replaced my intake gaskets this year. 3rd time 1250 paper gaskets suck only last 6 months before soaking up coolant. I went to the s3 steel core. and retorqued 4 times after every drive. I checked vac leaks etc all good except my secondary shaft on my carb the teflon seals need to be replaced.. it is a crazy shake like it has a 600 lift cam.. it is running a xe274h so should not be quite that choppy.. any thoughts on the pickup coil I do not have a new one on hand as can not buy in Canada have to order online and wait a couple weeks. Home depot sells them in usa for **** sakes!! They do not even know what a pickup coil is here and keep talking about an ignition coil...

[Broncojunkie]

Have you checked the harmonic balancer?

[78futura]

Have you checked the harmonic balancer?

It is 2 years old and the bolt is tight. The rubber looks good too. Its a 28oz balanced engine with the 28oz flex plate too..

[78futura]

If anyone can chime in that has spent days screwing around with duraspark distributors that would be great.. I wish I had snother one here. Will check a new 81 351m and see if the pickup is the same. The reluctor is broken when brother tried to remove so may have a free pickup coil from that one

[MERCURY MOTORSPORT]

That's the first thing I would've thought too. Either a partially seperated/un-bonded balancer (the rubber seal) or a cracked/broken motor mount

[78futura]

That's the first thing I would've thought too. Either a partially seperated/un-bonded balancer (the rubber seal) or a cracked/broken motor mount

I went all around on the balancer and is tight. I checked the water pump too etc. Driver side motor mount bolt I turned the nut almost 1/2 a turn to tighten.. they are energy suspension new mounts. Tranny mount tight and in good shape.

[MERCURY MOTORSPORT]

My 'ol Dad was a really old-school engine performance builder back in the day, him & his brothers used to work on my Grandfather's race cars. I'm kind of wondering about it and out of curiosity I'm going to run in by him when I talk with him later tonight. Aside from the aforementioned problems, he's probably going to mention the flywheel and/or a bent crankshaft or similar. Bumping this for you too . . . it'd be nice if maybe some of the Duraspark distributor guys would volunteer a few suggestions, whether a vacuum advance issue could cause a engine shake at certain RPM's or ??

[Jerry peachuer]

Point and shoot thermometer gun on each header see if one of the holes is dead
Could be broken spark plug or separated plug

I had 2 different autolite plugs do this to me

Sounds crazy but before you put spark plug in you shake it to see if ceramic separated or your plug socket has the rubber in it

Firing order and or cross fire I believe on cylinder 5/7 could be happening depending on plug wire routing also
Don't quote me on 5/7 but middle of the firing order has 2 cylinders firing and those wires should have a wire separator or put another wire in betwen them so they don't trigger each other
Not sure if this is common with duraspark ignition or not

[78futura]

Point and shoot thermometer gun on each header see if one of the holes is dead
Could be broken spark plug or separated plug

I had 2 different autolite plugs do this to me

Sounds crazy but before you put spark plug in you shake it to see if ceramic separated or your plug socket has the rubber in it

Firing order and or cross fire I believe on cylinder 5/7 could be happening depending on plug wire routing also
Don't quote me on 5/7 but middle of the firing order has 2 cylinders firing and those wires should have a wire separator or put another wire in betwen them so they don't trigger each other
Not sure if this is common with duraspark ignition or not

Temp gun they are all very close from a cold startup. I replaced the plugs just to check already. Also ohmed wires and ignition coil. Wondering if anyone has any expertise with the pickup coil going wonkey and what that can do?
I can rev it in neutral and do a couple 5k blasts and there is no missing or hesitation popping farting etc. Pipes are nice and clean( just put 2.5 rear pipes on made them myself straight out the back you can not even see them from the side on a futura that is not an easy task on the rhs rear with the brake line and fuel tank in the way...

[Jerry peachuer]

Nice tuck job on exhaust work
Is the balancer 28oz also

[78futura]

Nice tuck job on exhaust work
Is the balancer 28oz also

Yes it is

[Jerry peachuer]

Have the valves been recently lashed down

[Jerry peachuer]

valve could be not shutting/sealing missing making it shake by missing

Pickup coil can't offer any advice on what it would do
Your dizzy has a bushing and when bushing wears it could create and wobble slightly i guess which will go closer and further away (bent) from the fixed pickup coil

However performance distributors may offer sound advice for the duraspark dizzy and or there FAQs page

Ignition module could be messing with your signal also i guess

Is carb loading up during idle meaning when you rev out of the miss is it gas galore smell out exhaust?

Or is it just shaking and its a clean rev

Put timing light on it and stand next to it and slowly and steadily ease it to 2500 3200 rpm and see if timing jumping all over or if its steady and increasing smoothly decreasing smoothly

As far as home depo selling pickup coils I would pick a few up( no pun intended) but there automotive section is very bleak to say the least

[78futura]

valve could be not shutting/sealing missing making it shake by missing

Pickup coil can't offer any advice on what it would do
Your dizzy has a bushing and when bushing wears it could create and wobble slightly i guess which will go closer and further away (bent) from the fixed pickup coil

However performance distributors may offer sound advice for the duraspark dizzy and or there FAQs page

Ignition module could be messing with your signal also i guess

Is carb loading up during idle meaning when you rev out of the miss is it gas galore smell out exhaust?

Or is it just shaking and its a clean rev

Put timing light on it and stand next to it and slowly and steadily ease it to 2500 3200 rpm and see if timing jumping all over or if its steady and increasing smoothly decreasing smoothly

As far as home depo selling pickup coils I would pick a few up( no pun intended) but there automotive section is very bleak to say the least

Timing does not seem to jump. Lash set quite awhile ago. Prob 3 years? Car does load up when at idle sometimes and have to clear it up with a 5k..lol maybe floats are too high? Will have to check. Its a 600cfm vac sec holley. I am going to change the pickup coil then screw with it some more..

[78futura]

[Jerry peachuer]

Nice car

[78futura]

Nice car

Thanks. Thought I would add some pictures for fun..

[Jerry peachuer]

Looks like a lot of fun

[Walking-Tall]

Nice car. When exactly did the vibration begin (after cam change, other)? For the record, 230-degrees of intake duration @ .050 and a 110-degree lobe separation camshaft usually produces a fair amount of "choppy" in a 302. The primary idle feed restrictions in a 600 vacuum secondary (which LIST-#?) may actually not be big enough for your camshaft combination (slight richer (calibration) idle/off-idle needed), and the air gap intake manifold (slight richer (calibration) idle/off-idle needed) that simply does not put much heat into the carburetor... so lean misfire could be going on. For very bare bones starters, make sure that the engine is very much so up to operating temperature and is as fully heat soaked as it can be prior to adjusting the idle mixture screws... speaking of those, whereabouts are they set at as is right now?... Primary transfer slot exposure at idle?...

What's the initial timing at? If not close to or already at, it might be happier with 16- or 18-degrees BTDC initial timing, which no doubt will necessitate "re-curving" (limiting) the distributor's mechanical advance to only be providing 10 (distributor) degrees of centrifugal advance. In the distributor - is the thin cir-clip retainer there that holds the breaker plate down? You mentioned looseness. Without digging deep in reference materials, my experience with DuraSpark II distributors is that they either work or do not work.

[78futura]

Nice car. When exactly did the vibration begin (after cam change, other)? For the record, 230-degrees of intake duration @ .050 and a 110-degree lobe separation camshaft usually produces a fair amount of "choppy" in a 302. The primary idle feed restrictions in a 600 vacuum secondary (which LIST-#?) may actually not be big enough for your camshaft combination (slight richer (calibration) idle/off-idle needed), and the air gap intake manifold (slight richer (calibration) idle/off-idle needed) that simply does not put much heat into the carburetor... so lean misfire could be going on. For very bare bones starters, make sure that the engine is very much so up to operating temperature and is as fully heat soaked as it can be prior to adjusting the idle mixture screws... speaking of those, whereabouts are they set at as is right now?... Primary transfer slot exposure at idle?...

What's the initial timing at? If not close to or already at, it might be happier with 16- or 18-degrees BTDC initial timing, which no doubt will necessitate "re-curving" (limiting) the distributor's mechanical advance to only be providing 10 (distributor) degrees of centrifugal advance. In the distributor - is the thin cir-clip retainer there that holds the breaker plate down? You mentioned looseness. Without digging deep in reference materials, my experience with DuraSpark II distributors is that they either work or do not work.

I think its an 1850 list. Running 18advance at idle with vac advance pulling that in hooked up to the manifold port. 2 deg initail and maybe 25 total. Very heavy springs on the distributor so mechanical late. I tried every other combo but running 91 octane and with 10.2:1 compression will detonate and this seems to be the best setup.
Back to the carb curb idle is turned way down I opened the secondaries a bit to increase the idle. When it does warm up I do get a faster idle than lets say 160 F. Runs at 175F. Need to get a af gauge..

[78futura]

I think about 1 1/2 turns out. I noticed richening the mixture lots helps with off idle detonation but back to an idle will load up with fuel and sputter..
Not exactly sure when the weird vibe happened.
Welding in subframes right away. Hp+built tranny+ drag radials= twisted up fox. Lol

[Walking-Tall]

So I understand right, are you saying that it's at 18-degrees BTDC WITH the vacuum advance connected?... and only at 2-degrees without? If so, that's an issue, and would provide lotsa unhappy "choppy" idling for sure... and low speed off-idle will suffer due to retarding/reverting back to the 2-degrees or so...

With that cam and cylinder heads, it ought to like upward of 18-degrees BTDC initial, and 32- or 34-degrees total at upwards of 5000rpm... all measured/set without the vacuum advance in the picture.

So the vacuum advance can pulls in 16-degrees (you stated 18 combined pulled in, with 2 initial)? Must have a "8" stamped on it's stem? ... if less is needed with a performance curve setup (very often the case), the vacuum advance can that's originally intended for use in a 1974 390 F100 (Standard Motor Products part # VC230) is stamped with a "6", therefore providing 12-degrees crankshaft vacuum advance...

[Walking-Tall]

I think about 1 1/2 turns out. I noticed richening the mixture lots helps with off idle detonation but back to an idle will load up with fuel and sputter..
Not exactly sure when the weird vibe happened.
Welding in subframes right away. Hp+built tranny+ drag radials= twisted up fox. Lol

Yup, that's pretty good indication that the idle/off-idle calibration is lean for the combination...
The 1850's usually have 0.026" primary idle feed restrictions... I'd be installing (adjustable) 0.028" in a combination like yours... and (also adjustable) 0.070" primary idle air bleeds for starters... which would provide a pretty good initial window calibration for appropriate idling, off-idle, and transition...

[Walking-Tall]

For instance, my own 218-degrees intake duration @ .050 lift camshaft, ~9:1 compression, 87-octane running, ported E7TE headed, regular Performer RPM and presently a 600 vacuum secondary (0.026" primary idle feeds and 0.070" primary idle bleeds... haven't had a chance for much super-tuning in this department, but it works pretty good with crispy throttle response and light part-throttle acceleration so far), BBK shorties and 2-1/2" dual exhaust, 302 in my car, has a DuraSpark II distributor with a limited mechanical advance (10-degrees distributor (so 20-degrees crankshaft)), is presently set at 14-degrees BTDC initial with vacuum advance disconnected, and has the above stated VC230 vacuum advance can on it, that's regularly connected to full manifold vacuum... and I intend to bump the initial up another 2-4 degrees, because it'll likely stand it, will sharpen throttle response even more, and will smooth the mildly choppy idle some that it does have...

[78futura]

For instance, my own 218-degrees intake duration @ .050 lift camshaft, ~9:1 compression, 87-octane running, ported E7TE headed, regular Performer RPM and presently a 600 vacuum secondary (0.026" primary idle feeds and 0.070" primary idle bleeds... haven't had a chance for much super-tuning in this department, but it works pretty good with crispy throttle response and light part-throttle acceleration so far), BBK shorties and 2-1/2" dual exhaust, 302 in my car, has a DuraSpark II distributor with a limited mechanical advance (10-degrees distributor (so 20-degrees crankshaft)), is presently set at 14-degrees BTDC initial with vacuum advance disconnected, and has the above stated VC230 vacuum advance can on it, that's regularly connected to full manifold vacuum... and I intend to bump the initial up another 2-4 degrees, because it'll likely stand it, will sharpen throttle response even more, and will smooth the mildly choppy idle some that it does have...

What parts do I need and how hard is this to do? Something about
Drilling it out, tapping, do you need a af gauge to calibate or do you think I can hillbilly tune? Lol