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318 Poly Vibration

matthon

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I posted this on FABO in late October and they have helped greatly.
Figured there may be someone on this forum who isn't also on FABO who might be able to help.

Issue: slight vibration, never there for months, now remains constant at any rpm, never gets worse.

Details on everything:

Replaced an existing 318 poly in a 64 Fury that needed a rebuild with a running 318 poly from a 65 Plymouth that was rebuilt a number of years ago. I swapped my valve cover, oil pan and pickup. Motor is extremely clean inside, I painted the outside.

New MSD distributor, coil, starter and relay, voltage regulator, belts hoses, engine mounts, headers/exhaust, etc.

Battery came from another running car I had, alternator was tested and good.

Could not locate a replacement trans mount.

Ran really good, but had a slight hesitation above 50 so I rebuilt the carb, degreased it, carb cleaner, compressed air, and changed the plugs.

Idle mix screws were about 7 turns out when I got it, noticed before I rebuilt carb, part of instructions is to write down number of turns in before disassembling. Once rebuilt, wouldn't run well w/o screws out 7 turns. I thought way too much, plugs were not fouling or blackened, checked multiple times, ran well, didn't smell rich at all or eat gas. I address this and the timing later once I realize the timing mark doesn’t exist on my poly.

With a few adjustments it was running great and driven daily for roughly 2 months.

September 28: checked all plugs, looked good, installed new plugs I purchased earlier anyway.

October 8: pulled plugs to check, looked fine.

October 5: alternator died, I updated another car to an alternator with an internal regulator so I used the alternator from that car, charged battery. Next day drove fine for many hours on a parts run, left it idling for 30 minutes or so. Got home, shut it off, battery spent.

October 6: new battery installed, low on gas, drove to gas station, halfway there wouldn't move, wanted to stall, felt a vibration when it started moving. Made it, needed gas to get back. Ran better by the time I got home. Checked all plugs, pulled wires apart, re-crimped a few to be sure. Checked firing order, started, ran the same, realized I forgot to plug 1 wire in, vibration remained.

This is where the vibration started. Starts right up, idles nice, but has a slight vibration, which is the same at any rpm.

Vibration can be felt best on tops of fenders in front, on top of air cleaner, and sometimes with steering wheel at idle.

Disconnected belts/pulleys, not water pump, disconnected alternator, not alt, not power steering, no knocking noise, no oil in radiator, no metal in oil, pulled valve covers, all pushrods in place. In and out of reverse and drive, trans doesn't budge, mount doesn't move, engine moves a little, rubber mounts new, look fine, bolts tight.

October 25: checked the oil, a little bit of milky, been sitting over a month, ran it, looks fine. Some water comes out the tailpipe at startup, not green, no sweet smell, radiator has been the same level all along.

October 26: drove to work. Ran fine there, horrible on way home. Same with oil and antifreeze.

October 28: drained some oil, no water. Grounded each plug wire, no change from cylinder to cylinder. Noticed new Moroso plug wires were total crap, ordered new ones.

December 15: replaced plug wires. Needed to move it. Fired right up on a freezing cold day.

December 23: adjusted valves based on a thread on fbbo, cold method. All but a few were correct, #7 had zero. Checked oil drains on heads. Discovered I used the wrong base gasket from the kit, it had a few, which was preventing the PCV from working. Engine runs so well, starts no problem, sounds great, vibration.

December 29: put correct carb base gasket on, PCV works fine. Started fine, idles fine, oil looks good. Pulled all plugs, all black. I knew it was rich, but have checked replaced a few times, always looked good, probably from being rich and only been idling lately. Began compression test, per instructions, warm up engine to test, disconnected coil, open carb butterflies, crank same amount for all. Starting with odd at #1, 120, 120, 110, battery died, really, new a few months ago. Had to get back to family time so stuck the charger on it.

December 30: back to it today, cold engine, but did all starting with odd at #1, 150, 150, 145, 150, starting with #2, 145, 150, 140, 150. Pulled valve cover to help find #1 tdc. There is a timing tab on the cover, but balancer does not have a timing mark. Apparently this is the case with some polys. I have 3 polys, 2 have no mark, one has no balancer. Not a later balancer, not 180 off. Found tdc, set it to 10dg btdc for initial start, same as when I originally started engine. Rotor exactly on #1 at 10 dg btdc.

January 1: gap new plugs to .035, installed tach, set balancer mark to 10dg btdc, set rotor to #1 cylinder, reset idle mix screws to 2 1/2 out, pulled top of carb off and checked float level, cranked engine to make sure needle was closing, has clear fuel filter. Realized vacuum advance was connected to manifold vacuum on carb, moved to ported. Adjusted distributor to get to 10dg btdc at 600 rpm, put it in drive, reverse, idle dropped but was ok, no hint of stalling.

Drove it. Did great, ran great, sounded great, headers/dual exhaust, no issues at stop lights, didn't smell, shut down instantly, started perfect. Didn't mess with the idle mix screws at all, no more 7 turns out to keep it running. Came home a few times to check trans fluid, oil, bolts, etc. Took it back out, thoroughly enjoying it. At this point, I’ve somehow forgotten to even check for a vibration.

Decided to do a little interior work, make it look nicer.

30 mins later, started, idles much lower and quickly stalls in park or neutral, forget drive. Shaking, sounds horrible, smells worse, adjusted carb, etc, nothing works. Checked for vacuum leaks, none. Disconnected heater vacuum, heater/defroster doors run off manifold vacuum, nothing. Pinched fuel line to run it dry thinking maybe something was stuck in needle/seat because it smelled so bad, nothing.

Pulled 2 plugs both half black half white, brand new white. Unable to find info on this scenario.

January 6: Set #1 tdc compression, removed valve cover to make sure, set distributor/rotor to #1, cleaned up cap and rotor, checked/cleaned up coil wires, checked all plug wires are clicked on all the way.

Started, let warm up, advanced timing to 10dg btdc, set idle to about 700 rpm, checked timing reset to 10dg, ended up running best at around 12-13dg. Set idle mixture using vacuum gauge hooked to manifold vacuum on carb. Checked idle in drive and reverse. Double checked timing, tightened up distributor, took for a ride. Runs good, not much different than last time.

Changed coil to the exact same coil, brand new coil I just received for another car, no difference. Checked water pump, alternator, power steering pump, again, no issues. A little valve chatter at higher rpm when driving, nothing major, very small adjustments to timing and idle solved it.

Ran extremely well, really well, nothing new there, but that vibration. Vibration is more obvious, if that is the correct term, seems more prevalent at the right front, passenger side.

I was holding a small long screwdriver leaning on the passenger fender and noticed the upper horn vibrating, then I noticed the screwdriver in my hand vibrating at the same frequency.

Put a big long screwdriver to the fuel pump, not vibrating or knocking.


Checked, tightened, changed, replaced everything, fixed a tranny leak at the kickdown, put new floor mats in, nothing!

Everything works, except the clock, trans goes into gear and shifts great, solid car.

The vibration started after the battery died, ran great, shut off, battery dead, replaced, ran like crap. The only thing I did before working on interior was to disconnect the battery so the interior light wouldn't burn the lens up.

I can't find anyone, professional or otherwise, who can either take the time to work on an old car, can figure out the issue, or even believes there is an issue.

Slight vibration, never there for months, now remains constant at any rpm, never gets worse.

Screenshot_20190107-145919.png
 
If the vibration doesn't change with increased revs then it can't be directly related to the rotating assembly, and the fact the vibration is more noticeable on a part attached to the car rather than the engine itself points to a harmonic being transferred from elsewhere. Is it the same with the car motionless at idle/revving engine as it is when driving at idle revs or driving at speed? Is it the same with transmission in park as in neutral? Is it less noticeable when driving? Could be transmission related?
 
Is it the same with the car motionless at idle/revving engine as it is when driving at idle revs or driving at speed?
If I recall correctly it does not change. I will double check this, specifically idle motionless vs idle moving. Overall, if I rev it up, or hold it at a higher rpm, I do not sense an increase in vibration, so it is hard to determine if it disappears.

Is it the same with transmission in park as in neutral?
Yes. I will double check though.

Is it less noticeable when driving?
Yes.

Could be transmission related?
I thought so as well, problem is, as you may know, there is no way to easily separate the engine from trans as the ring gear is attached to the converter, so I can't start it without being connected to the trans.

Any suggestion or question, I have been going back and checking.
 
66sat brought up some very good question that need answering. couple things jump to my mind. could vacuum advance line possibly have cracked even slightly? also when was the last time you checked the points (I don't know if your distributor has points?) if it happened around the time a new battery was put in leads me to believe that possibly having a failing battery in the car for a while had some effect on some part of the electrical system. maybe not tho. did you put in new motor mounts when you swapped the engine and how long ago was that? also does the car always run fine, rev up smoothly, regardless of the fact that it vibrates the body?
 
Sorry, MSD electronic, no points.
I rewired the starter and solenoid, dizzy, and put in new pos/neg cables.
I actually changed the vacuum advance hose to a new piece on January 1.
New motor mounts went in when I swapped the engine in July. Not a torque monster by any means but runs well, mounts look good, checked all bolts.
 
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When I checked the float level on Jan 1 I pulled the accelerator pump plunger out, checked for debris in there and in the float bowls. I know I changed the filter twice to a clear filter, first time I saw debris I changed it immediately, I bought a bunch of filters, and it is currently full of gas. I also cleaned the gas tank out multiple times.
Accel pump sprays gas nice, motor revs strong, all plugs looked the same as every other plug each time I pulled/changed them.

I can easily pull the carb again, pull it apart and spray it out, blow it out, not a big deal.

I appreciate any feedback, just trying to clarify what I have done and what I am seeing.
 
Looking at pics to check what I did and when, never saw wiring before with numbers on the wires
20190107_172136.jpg
 
What advice did the guys on FABO give you? You said they were very helpful. You've done a ton of checks but I wonder if you're not seeing the wood for the trees. If the vibration frequency doesn't change with revs or speed then it can't be directly related to the engine. I think all the battery and carb problems are unrelated and coincidental and are leading you down blind alleys.
I'm not a mechanic however, so maybe I'm talking out of my ***! I'm just thinking that like with finding water leaks, finding vibrations is similar in that where it finishes can be far from where it originates.
If it vibrates when the car is static that rules out certain things (wheel bearings etc) but if it's when it's moving then that opens up other things including suspension, exhaust etc.
 
BELT TENSION? sounds like maybe something is not bolted down enough (something connected to engine block) or something developed slight play. not sure if you have checked the alternator or power steering pump belts/pullys. if the engine revs up nice and smooth than I doubt its carburetor. also you sound like you've done a lot of replacing/updating to the electrical system which was working fine until this happened... so probably not that either. could be a transmission issue but I don't know much about transmissions.
 
I posted on FABO on Oct 25, so basically everything after that date.

I completely agree, I'm not seeing the forest thru the trees. But I'm also going coo coo for coco puffs trying to figure this out. I even thought to myself, I shouldn't have posted about the new battery and disconnecting to do interior work, that'll lead everyone down one path, potentially the wrong path, because I keep thinking I took a wrong turn myself.

Definitely static, car not moving. I almost wish it was when moving, or got worse with speed, it seems easier to figure out at this point.

The way that horn was vibrating, you had to look directly at it to see it, and stop it to verify, I didn't notice it ever before. This car is pretty original, solid, and still put together. No rattling or noises at all.
 
Checked all belts/pulleys. Disconnected all and ran it. Tightened them up multiple times. Electrical is in excellent shape, just updated what I needed.

I've tightened bolts cold, hot, in a house, with a mouse, etc.

I've searched the interweb for months.

Wish I could run it w/o trans. I'm guessing percentage of vibration getting worse when driving goes up if it's the trans, but I don't know.

I don't know anything at the moment.
 
Is it the same with the car motionless at idle/revving engine as it is when driving at idle revs or driving at speed?
At idle motionless the same as at idle in drive.
Driving at speed difficult to tell, I would say yes.

Is it the same with transmission in park as in neutral?
Yes. Pushbutton trans if that matters.

Is it less noticeable when driving?
Yes.

Just drove it around, ran great, seemed to start to run not as good when I got back.

I checked the trans to engine bolts, just because, one was a little loose, no change to vibration.
20190107_190622.jpg
 
The fact the vibration is there when the engine is running great and when it's running like crap means you can eliminate certain things surely e.g. carb, ignition. Also if it's both when the car is static and moving then you can eliminate everything south of the transmission. Does it vibrate the same when it's first started and engine is cold or does it start only the car is warmed up?
Maybe it's been there from the start and you didn't notice because it's less noticeable when driving, and you're only noticing it now since you've had it idling when checking the battery/alternator way back in October? Did you install the replacement engine just out of interest?
If you slowly increase the revs while watching the motor does it smooth out at any point?
Is the fan fixed or a clutch fan? If it is a clutch fan maybe it's shagged and due to the coupling it doesn't increase in revs with the engine hence the vibration being the same at all revs? I know you said you've tried it with the alternator belt disconnected but the waterpump/fan was still connected. Check the fans bolts anyway, if it's new engine stuff comes loose.
Is the radiator mounted securely - if not maybe a vibration from the hoses being transferred to the radiator and then the support?
 
Engine cold or hot.

It definitely started after the battery install. I brought a friend with me on the parts run the day before and it was smooth as silk. We were all over it showing it off while it idled for 30 minutes w/o issue.

Installed replacement engine because it was close by and priced at a fraction of what it would cost to rebuild the original. The original had severe water/rust damage in one cylinder, nest of some kind, and was stuck. I've known about this car for over 10 years, guy drove it, then parked in a dry garage. There was another nest in the tailgate, and not so much as a mouse dropping anywhere else.

Slowly increasing revs it doesn't smooth out. I held my hand on the air cleaner and I can feel it slowly dissipate, meaning the sound/rpms of the engine start to mask it, but it doesn't go away.

Fixed original fan. Checked it several times.

Water pump/fan and alternator on the same belt.

Radiator is secure. I was just pushing on it earlier while warming up my hands on it.

I had an Accel dizzy in another car, and it would eat caps/rotors, always had to keep a spare with me. Switched to MSD, haven't had an issue in over a year.
The running bad sometimes reminds me of that, but the Accel would run like crap then quickly not run at all.

Thinking of ordering a new cap/rotor, but not thinking it will solve the vibration issue.

This is definitely helping, thank you all, just can't get this though.
What the heck are we missing?

Fyi, that's not a real ballast resistor, it's fake, only purpose is to provide 'run' power after start. I took it from my other car when I re-wired that car. I checked it again, no issues.

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They put a new battery in it. could they have possibly messed with the battery tray. maybe its not sitting in there right. the battery is heavy and if its it not fully secure that could cause a vibration issue... maybe!!! maybe it got rusty from the acid at one point and putting a new battery broke a mount or something like that? you probably already checked that but who knows!
 
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could the timing chain assembly have worn out? or water pump(but that would probably only be once it warmed up?
 
It didn't have a battery when I bought it. I bought a new battery hold down kit and put a working battery in it.
Battery tray is rock solid with no rust. Might be hard to see but still has factory paint on it.

Keep the suggestions coming please, I'm losing my mind here.

20180505_184957.jpg
 
As far as I know a worn timing chain, or one that jumped, would display additional symptoms, metal shavings, mis-fire, noise, backfire, etc.
I also don't have slack in the valvetrain while manually moving the crank back and forth. I've done it multiple times trying to get tdc exact.

Open to more opinions on this scenario though.
Also if there is a better way to test for this.
I can check the timing again at the same rpm of 700 and see if it changed.
I don't ever recall that it changed on it's own before.

Water pump doesn't budge, I loosen the alt/water pump belt each time to spin the crank by hand otherwise the fan gets in the way of the ratchet.
 
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do you know anyone with one of those electrical tune up machines to hook up to your engine who might be able to help you. that analysis might answer your problem right there. they don't have to be a shop that works on cars this old, I'd imagine some shop near you has one. something like a "sun tune up tester"

also for the record we have the exact same car, as you probably know. poly 318 and everything, pretty much all stock. the only difference is that mine has a 4 barrel and I'm still running stock distributor with points. my engine and tranny were rebuilt by the PO (no way to verify) My wagon does shake at idle, the whole car a little bit, I've always thought this was normal. but I think my cam was reground to a little hotter specs also. also been working on the car constantly and have not had a chance to drive it really. the basket case that it is, I've taken it for a few test drives and it basically smooths out when driving as I remember.

have you experienced loss of power? or just vibration, or is it hard to tell?
 
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