Have you swapped the tires front to back?

 

No. I had a new set put on before starting body work several years ago. I don't recall whether I noticed the vibration before all that work. That work included replacing floor pans (just under your feet ie tunnel remained) and trunk pan and rear 18 inches of frame rails and reworked the rockers.

I'll swap the tires around when I get the drive shaft back.

 

I am sure, the sloop in tail shaft of trans causing your vibration

 

When you say it seems to quit when you turn to the left it has me thinking it could be a wheel bearing. Improvement by steering to the left would point at a left side bearing being culprit. And feeling it in the steering wheel I'd start looking up front. Check the front left wheel bearing.

 

I have a 62 convertible with original 6 cyl automatic. It has a rhythmic vibration that starts about 30 mph then goes away above 50 mph. Also it kind of quits when I steer to the left. When I say rhythmic, it's hard to describe. Kinda
rrRRRRrr...rrRRRRrr..rrRRRRrr.. About a second or 2 between iterations and doesn't seem to speed up with increased mph. It's not a big vibration. I just feel it in the steering wheel.

I've done a lot of restoring on this old thing. The trans was completely rebuilt just before I bought it. I've rebuild the front suspension and steering and had the rear end rebuilt. Today I'm taking the drive shaft to a shop to have him spin it up to check the balance. Visually it looks OK.

One question for now: can there be any play in the shaft coming out of the trans? I pulled the drive shaft yesterday and I can wiggle the end of the shaft just a little. Maybe a 1/16 inch or so.

When you say you feel it in the steering wheel, that is an indication to me that your problem is in the front end. As bracketchev70 stated, I would start with wheels and tires. Have the tires re-balanced. Are your new wheels quality hub centric wheels? If not perhaps a set of hub rings would help. In my mind this is always the first, and least expensive place to start.

 

I don't know what hub centric wheels are or hub rings. Here is a pic of the chrome wheels that were on it when I bought it. They are 14 inch 4 lugs so I hope I can stay with them. It took me forever to find a stock 14 inch 4 lug for a spare.
Also I'll show some pics from when I did a brake job. That was about the first thing I did to it when I bought it 6 years ago.
Looking at those bearing pics reminds me I did have an issue with the left front. Seems I couldn't get the inner bearing off easily. I had to smooth the spindle with emery cloth a little.

 

Get the front end off the ground and spin the wheel. Does it feel smooth? Or a bit choppy? Try to rock it side to side to check for any play. Can't hurt to replace the bearing again. Be sure to grease it up good(via packing it) when reinstalling and don't overtighten it. Tighten the bearing just until you have noticeable drag then back it off until the cotter pin can be inserted. No more than 1/4 turn. Spin again to make sure it feels smooth. I'm sure the other fellas around here have some other good procedures for doing this. Hope this helps.

 

I'm fairly familiar with all that procedure but I'll check it out again.

I just took a 5 second video of the wobble in the transmission output shaft but I guess I can't upload it it here. If anyone wants to view it email me at kenwinchester@gmail.com and I'll send it.

 

I'm not sure what the accepted play tolerance would be for the output shaft. I'll take a knee on that one. Interested to see what others come back with...

 

Hey, Winch. Thinking front end or bearings as well. Also, if an upper ball joint is worn and you make a turn, it loads the ball joint differently and can throw a wheel or wheels out of alignment. Check wear on the front tires for that as you might be seeing some choppy wear.

 

Probably not enough miles on the tires yet to tell. Also all ball joints have been replaced.

 

Might be play somewhere. Have you checked alignment? Does it have the cams for the lower control arm or a 'lockout kit'? A bump could knock it out of alignment, and that noise could be a result of that.

 

It was aligned probably less than a hundred miles ago. It's all stock. I remember they had a hard time getting the right side caster (I think) because they couldn't tighten the nut on the strut rod down quite far enough. They got it within tolerance but it could have used a little more. It seems to track fairly straight.

What brand did you use? There are some junk ones available that are not worth a penny right out of the box.

Moog.

I think I found it or at least a good bit of it. I checked the front wheel bearings. Tires have no play left to right and up and down but I noticed when I spin it by hand it went 4 or 5 turns so I checked the bearings. I was able to tighten the left one notch with a channel lock but that didn't make it spin much less. I put a socket on it and it pulled it in when I turned it down to the next notch. I figured that would be too tight but it now spins free hand 1 1/2 to 2 turns. It took tightening the right side one notch to get it to spin with that much drag. Took it for a drive to get gas and it's much better. Still a little vibration around 50 but I didn't notice it at all under 50.

When I put the driveshaft back in I feel no play at the trans shaft so I won't have the DS balanced today anyway.

One more unrelated question. Can gas evaporate considerably if the car is not driven? According to my records I filled up September of last year. Today it took 14 gallons to fill it to where the pump clicks off (no top off). But I've only driven 85 miles since last September! That's 6 mpg.

 

One question for now: can there be any play in the shaft coming out of the trans? I pulled the drive shaft yesterday and I can wiggle the end of the shaft just a little. Maybe a 1/16 inch or so.

Yes, you can wiggle the output shaft with the driveshaft removed. The output shaft is supported by the driveshaft yoke which rides on the tailshaft bushing. If you can wiggle the front yoke of the driveshaft when the shaft is installed, then the tailshaft bushing is worn and can cause a vibration.

 

it was said in posts above, check left wheel bearing. a left turn would put more weight to the front right an less on the left front wheel.

 

Also all ball joints have been replaced.

What brand did you use? There are some junk ones available that are not worth a penny right out of the box.

 

Winch,

Glad you seemed to have found the issue with the vibration.

How often do you start the vehicle(and for how long) besides only driving it 85 miles in a year?
- Nick

 

It gets driven very little. Being a vert with the top always down I only drive it on really nice days. Plus I've been forever waiting for the interior to get done so it doesn't have the passenger seat in it right now. I try to drive it around the subdivision a couple of miles once a month or so but when the weather doesn't permit that I'll start it and let it run until it's warm maybe once a month. Probably less in the winter.

I'm hope to get it painted this fall. Just a freshen up as the body is pretty good. And hopefully I'll get the interior back so next spring I plan to make it my daily driver. But then I'm retired and only go to town (5 miles) once a week or so.

You got me wondering how many miles I've put on it since I bought it in August of 2016. The title doesn't have the mileage but I have the receipt from the transmission rebuild in June 2015 and it now only has 2,300 more miles than then.

I found the inspection report from when I bought it and I have put 536 miles on it since then! I need to drive it more.

 

Starting it once month on top of sitting that long isn't surprising you consumed that much gas, hence lowering the mpg drastically. I wouldn't be too worried about it. My opinion of course. Sometime you should take it out, fill it up and drive it for 50-60 miles or more. Refill it before you bring it back home and figure your true gas mileage.

 

Good advice. I just ran to town again and drove it. Hot day but worth it for all the thumbs up.

 

Also, check to see if your carb is percolating, especially after stopping it when the engine has been warm. Even more fuel loss. 6 mpg is not at all what you should be getting.

 

How do I identify percolating? And if it is, what is the cure for that?

 

I've had tire cords separate several times on me.
Jack the tire off the ground and spin it watching the tread pattern for uniformity.
I've found that TOYO tires are known for this, but it could happen with any manufacturer.

 

Percolation is when the carb gets hot enough to boil the fuel in the carb. Fuel with ethanol in it has a greater tendency to boil. You might notice that after getting the car hot (especially on hot days) that after you shut the car off the fuel in the carb will boil. Sometimes you can hear it, or you might see it leaking out of the carb, or into the throttle bore. While the car is running, and fuel is flowing into and out of the carb, that fuel is cooling the fuel lines and carb. After shutting it off, it creates a heat soak condition and the fuel in the carb heats up. If it's hot enough, it will boil. If you have a clear fuel filter you might notice it there, too.
Many old cars do this and nothing is required to fix it. My '47 Willys does it on hot days. Many times it will boil the fuel out of the carb, it will flow into the intake manifold, and when I start it again while it is still hot it will take a second or two to clear out and run OK. If the fuel boils while the engine is running, it can cause the engine to run too rich or too lean. Then you have to work at insulating the fuel lines, or insulating the intake manifold from the carb. Things like that will reduce the carb and fuel temps enough that it won't boil while the car is running.

 

Steve G makes a good point, too. Many of us have our cars sitting on their tires for half a year, or some have tires older than 6 or 7 years. Other ways to check possible tread separation are to look for cracks in the sidewall close to the tread, and, if the tire has some miles on it, different tread depth at say, 12 points around the tire. If you're finding that the tread is really low in one spot: tread separation.

 

what's the age on them tires? More than 10 years old and they done, these days.