Flywheel to block alignment

[Eric S]

Checking an engine, I measured back of flywheel to rear o f block and I noticed a difference of around .060", left to right.
Turned the engine 180° and difference remained but the small gap went from one side to the other
Looks like the flywheel is slightly bent.
Now it's.060" but I have no idea if it means anything, if it's too much or within tolerance?
Engine was running fine and don't want to fix what isn't broken ..

[simplyconnected]

The flex plate should run true. Since a flywheel is machined, it should run even truer. I can't think of anything that would bend a flex plate. It is possible that some kind of 'junk', like rust, was not cleaned off the crankshaft before the flex plate was installed.

A few thou at the center will be more drastic five inches out. I'm more concerned about the pressure plate or torque converter that bolts to the flywheel or flex plate. Can you feel a shake with increased RPM?

[Eric S]

No shake, all was running fine.
What is the difference between a flywheel and a flexplate?
Does removing the plate to check and clean the surfaces involve anything else than removing a few bolts and reinstall?

[simplyconnected]

No shake, all was running fine.
What is the difference between a flywheel and a flexplate?
Does removing the plate to check and clean the surfaces involve anything else than removing a few bolts and reinstall?

A flexplate and a flywheel both have the starter ring gear. That's the only thing they have in common.

A flexplate is used for automatic transmissions to mount the torque converter.
Manual transmissions have a clutch with a pressure plate that bolts to the flywheel.

Removing the flexplate or flywheel requires the transmission (and driveshaft) to be disconnected just to get to the crankshaft bolts. Usually, the exhaust pipes must be removed first.
It's not an easy or quick task. - Dave

[Eric S]

Well the engine is hanging on my engine stand....

[simplyconnected]

Eric, you don't say whether you have a stick or automatic. In either case, unbolt the flex plate or flywheel and clean the mating faces of the crank flange and flywheel. Then re-assemble and check the runout again.

If your engine is on a stand, then you really don't know if it vibrates.

[Eric S]

It's an automatic.
engine was running in the car and running fine. As I said before I don't want to fix what is not broken.
Will pull off the flexplate and check.
Another concern though.
I had to replace the flywheel on my Cobra's FE and it is sturdily screwed mon the engine.
On this small block, the flexplate is also well locked but the torque converter is held by just 3 screws and 3 small mounting tabs. This seems to be a light connection between engine and gear box. I know it works but makes me wonder ...

[simplyconnected]

...I had to replace the flywheel on my Cobra's FE and it is sturdily screwed mon the engine.
On this small block, the flexplate is also well locked but the torque converter is held by just 3 screws and 3 small mounting tabs...

FE crankshafts use six bolts like this, including the reinforcement ring:

DSCN6990.jpg
What small block engine are you referring to? I've never seen torque converter mounting with fewer than FOUR studs and nuts, like this:

DSCN6988[1].jpg

What do you mean by, '3 small mounting tabs'?
Do you have pictures? - Dave

[Eric S]

My engine is not a Ford
Or imagine a Mustang going to a party and wearing a bowtie.
But 3 or 4 bolts seems not too much.
They are mounted farther apart and the longer radius means less torque. Anyway it worked for decades so it should be enough...

[simplyconnected]

Eric, it's customary to let us know exactly what engine we're talking about.
No wonder there aren't any pics.

[Eric S]

I asked generic questions that may apply to any engine, I guess.
I didn't want to step in asking "what do you think about my Chevy engine" here.
Didn't wanted to hide anything either.
Sorry if I hurt you. Wasn't intended, really, and we all appreciate your expertise, time, dedication and help.
As for the pics, it's just I didn't have them available.
Now do we have a space on this forum for non Ford topics?
Is it tolerated at all (I should have asked first)?