Starter grinding and car vibrating

[TheClarkster]

I just got back from checking out a '68 Cougar that I'm very interested in buying. The only two things that keep me from plopping down the $2000 right now are:

• Cranking the car over produces a grinding noise
• The car vibrates more violently the faster you drive

Is there any one thing that could be causing both of these? I've looked on Cougar boards and so far the best explanation I've seen had to do with the Torque converter bolts missing the holes and bending the flywheel(I think that's what it said). So now I turn to the TFP gearheads to help me!

[MSD]

The bent flywheel can do both, or you may have a bad starter and bad engine mounts. Either way, you'll probably be putting a few hundred dollars into the car to get it up and running. If you have any gearhead friends or know a local mechanic, have them look at it and they can probably tell you. That's a good deal for a car in running condition.

[TheClarkster]

In either of those cases would it be alright to drive it about 30 miles on surface streets back to my house? The guy who has it now has been driving it for a couple months with the vibrating so I'm assuming the problem hasn't worsened with driving on it.

[godxzilla]

could be a bad starter motor and some unbalanced tires. I would buy it. I dont think there is anything thats a deal killer in your description. Maybe tell him you found a starter for 100 and you need to knock that off the price.

having the flywheel resurfaced or replaced is not a major deal but while you are at it, may as well give it a clutch.

[TheClarkster]

Well the guy is delivering the car to me on Wednesday, so at least I won't break it driving it home. Where would I take it to have the flywheel and Torque Converter checked out? Would my 76 station mechanic be able to do that?

[Peryn]

Before you start spending the big bucks for transmission diagnostics or repairs, try checking the cheap/easy things. Like balancing the tires. At what speed does it start vibrating noticably? Seems to me that if it were a tranny/flywheel thing, then the vibration would be related to engine rpms, not speed. Are there any noises when its vibrating (humming, buzzing, etc)? The most common cause of car vibration is out of balance tires. Spend $50 or find a freind to balance them for you. Also, how long has the car been sitting? There is always the chance that your tires are flat-spotting and getting out of round. In which case new rubber may be needed and a balance wont help.

Also, its an old car, has the starter ever been replaced? how long ago. There is a chance that a $60 starter will solve the grinding problems. If the drive gear on the starter isn't enaging all the way or is fubared, it will grind. The car will still start, but youll start to take out the teeth on your flywheel. Pull your starter out of the car, take a look at the teeth and get a general idea of the condition of your starter.


I guess it just seems like such a stretch to me to go from "grinding and vibrating" to toqrue converter bending the flywheel. Check the simple, easy, cheapo stuff first.

[merkerguitars]

Well the grinding is usually a sign of the starter drive going bad or being misaligned. Like many said could be the flywheel or other things. A good mechanic should be able to fix it. Anyhow...a 68 cougar is a kick ass car, definately a head turner.

[irseg]

Is the vibration dependent on engine RPM or the speed you're going down the road? Does it do it if you rev the car in neutral?

Best case would be bad starter and unbalanced/flatspotted tires.

Worst case would be crankshaft bearings that are so worn that the flywheel wobbles and no longer aligns properly with the starter.

[godxzilla]

im with peryn. that was my response as well, only mine was much less thought out and detailed! hats off peryn!

just get a balance and clean the contacts on your starter, for starters! (bad pun)

Mikey

[tspikes51]

Definately check the tires for belt wear, and rev the engine while in neutral and stopped. If the vibration is still there, then start checking out your flywheel/tc/crankshaft.

[TheClarkster]

As a followup to my problem:
The starter is replaced and the grinding when you start the car is gone.
We checked the flywheel and motor mounts.
The car vibrates noticably(sp?) only while driving. Revving the engine in park does not cause vibration at all. The vibration is bad when going somewhere around 30 mph and gets very bad while coasting at those speeds. The vibration reduces by a bunch if you shift it into neutral at those speeds though.
Any more ideas or diagnostic tests we could do?
Thanks

[lk_3000]

Check the tires and see if the lug nuts are tight. Happened to my dad's car when i changed his tire in the snow.

[MSD]

Originally Posted by TheClarkster

As a followup to my problem:
The car vibrates noticably(sp?) only while driving. Revving the engine in park does not cause vibration at all. The vibration is bad when going somewhere around 30 mph and gets very bad while coasting at those speeds. The vibration reduces by a bunch if you shift it into neutral at those speeds though.
Any more ideas or diagnostic tests we could do?
Thanks

I believe you may have a bad second gear, or on an auto, a bad two-three accumulator. This is what happens when you're driving near the speed at which the transmission shifts: a seal wears out in the accumulator, the drop in pressure druing the shift can cause it to shift back into second, which kicks the pressure up, making it shift into third, which drops the pressure halfway through the shift, dropping it back into second, and so on ...

[TheClarkster]

Originally Posted by MrSelfDestruct

I believe you may have a bad second gear, or on an auto, a bad two-three accumulator. This is what happens when you're driving near the speed at which the transmission shifts: a seal wears out in the accumulator, the drop in pressure druing the shift can cause it to shift back into second, which kicks the pressure up, making it shift into third, which drops the pressure halfway through the shift, dropping it back into second, and so on ...

And there's probably no way to really test this on my own is there? I don't have a tach in the car, and sadly the speedometer is out of commission. And it's a bigger project than just a one day drop off at the mechanics to give the engine and tranny a look over isn't it?

[MSD]

Originally Posted by TheClarkster

And there's probably no way to really test this on my own is there? I don't have a tach in the car, and sadly the speedometer is out of commission. And it's a bigger project than just a one day drop off at the mechanics to give the engine and tranny a look over isn't it?

Not necessarily. Once you have an appointment, you should be able to have your car back in a few hours. If you take it to a transmission place like Aamco, they can probably tell you what's wrong with it in less than two hours, assuming they have the equipment to inspect an old transmission like that. If it is bad, you might want to consider getting a new 5-speed or 6-speed that will get you significantly better gas mileage than the old thing in there, unless you're planning to keep it stock.

[TheClarkster]

Originally Posted by MrSelfDestruct

Not necessarily. Once you have an appointment, you should be able to have your car back in a few hours. If you take it to a transmission place like Aamco, they can probably tell you what's wrong with it in less than two hours, assuming they have the equipment to inspect an old transmission like that. If it is bad, you might want to consider getting a new 5-speed or 6-speed that will get you significantly better gas mileage than the old thing in there, unless you're planning to keep it stock.

Keeping it stock doesn't concern me as the engine and tranny are both from a 69 Cougar. Maybe I'll look for an Aamco or some similar transmission place tomorrow.

[irseg]

I'd check a lot of things before suspecting that the transmission is the culprit. Plus the problem MrSelfDestruct described would be more of a rapid surging than a vibration. BTW, does the steering wheel shake, or is it more something you feel in your butt?

I had a car that had a pretty bad vibration at highway speed when coasting in gear or accelerating. Shifting into neutral or giving it just the right amount of gas to maintain speed smoothed it out considerably. Turned out to be the front wheel bearings.

[TheClarkster]

You can definetely feel it in the steering wheel, but it's apparent everywhere. I mean the damn sun visor falls down when it gets bad enough.

[godxzilla]

did you balance the tires?

[tspikes51]

You'd be suprised at what a new set of tires can do.