Flywheel alignment

kbrandt

kbrandt

Junior Member
I'm relatively new to Model A's. I bought my '30 Tudor about five years ago. I drove it around for about six months before it lost a timing gear. In the course of repairing that, one of the local experts found cracks in the block in bad places so I gave up on that engine.

I replaced it with an engine I bought off of Craigs list. Supposedly the seller had had it rebuilt 10+ years ago as the spare for his coupe. He was getting out of the hobby and selling the car too. I don't have 100% confidence in the engine, but haven't seen anything to indicate he wasn't telling the truth.

After dragging my feet for years, I got the car running again last month. I've driven it around the neighborhood half a dozen times and it's doing okay. The one thing I've noticed is it shakes much more than the previous engine did.

After reading the Les Andrews book more thoroughly, I realized that I skipped aligning the flywheel. Opps...

So my question is what should I do next? Can I drive it without risking trashing the bearings? I'd kind of like to enjoy the car for a little while before taking it apart again.

As for fixing it, is it better to pull the engine again, or can I do it easily enough by pulling the transmission? Given the choice, I'd rather pull the transmission as that would give me a chance to clean it up and maybe change some seals and gaskets.
 
Maybe start with some easy checks. You can check the runout if the flywheel after removing the starter. Usually the symptom of a miss aligned flywheel is clutch chatter or troubles. If the flywheel is out of balance, that could cause some shaking. Maybe your old engine was built better and to closer tolerances. Did you make bearing and valve adjustments on the newer engine?
 
J Franklin said:
Maybe start with some easy checks. You can check the runout if the flywheel after removing the starter. Usually the symptom of a miss aligned flywheel is clutch chatter or troubles. If the flywheel is out of balance, that could cause some shaking. Maybe your old engine was built better and to closer tolerances. Did you make bearing and valve adjustments on the newer engine?
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X2 on checking valve lash. My 31 idled rough which no amount of carb adjusting would help. Problem was caused by one lifter with too little clearance. Easy enough to check and adjust (if you have adjustable lifters).
 
When does it shake ? Sitting still at idle or higher engine speed ? Or running down the road ?

Does the clutch chatter ?

If it does shake sitting still, it might help to rotate the flywheel 180. Thats a lot of work. If doing that then check the flywheel for runout and set the pressure plate fingers.
 
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J Franklin said:
Maybe start with some easy checks. You can check the runout if the flywheel after removing the starter. Usually the symptom of a miss aligned flywheel is clutch chatter or troubles. If the flywheel is out of balance, that could cause some shaking. Maybe your old engine was built better and to closer tolerances. Did you make bearing and valve adjustments on the newer engine?
Click to expand...

That's a good idea to measure the flywheel runout through the starter opening. I'll need to get a better dial indicator to do that.

I didn't make any valve or bearing adjustments on the new engine.
 
Patrick L. said:
When does it shake ? Sitting still at idle or higher engine speed ? Or running down the road ?

Does the clutch chatter ?

If it does shake sitting still, it might help to rotate the flywheel 180. Thats a lot of work. If doing that then check the flywheel for runout and set the pressure plate fingers.
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It shakes at all RPMs. It gets more intense as RPMs increase.

The clutch chatters a little but it's not bad. I didn't adjust the clutch fingers until after the engine was installed in the car so I don't think I did that precise a job.
 
Mulletwagon said:
X2 on checking valve lash. My 31 idled rough which no amount of carb adjusting would help. Problem was caused by one lifter with too little clearance. Easy enough to check and adjust (if you have adjustable lifters).
Click to expand...

It does have adjustable lifters. Maybe I'll try that before resorting to pulling either the engine or transmission.
 
Guys, you don't think it has a loose rod cap do ya? In any event, I'd say that engine is going to have to come out, to be checked over. Don't let someone tell you rebuild, just over one thing. Do yourself a favor and do a compression check before removal. I bet the flywheel is out of balance, and the crankshaft likely has no counterweights.
 
do as many checks and diagnosis with the engine in the car and running. you can test things.
an easy way to see if it is running on all cylinders is to start it and make it run as good as possible. then at an idle short out one spark plug at a time and see if it changes the way it runs.

if it were i, and if the flywheel and bell housing need aligning i would pull the engine. but only once i have done as much testing and diagnosis as i can.
 
Flywheel runout ??? Not likely unless the crank flange was out. The runout to be tested should be to insure that the flywheel housing has been shimmed to be in alignment with the crank flange to insure that the clutch and transmission main shaft are not at an angle to each other. You are not going to determine that by measuring the flywheel thru the starter hole. Any deviation that you may read thru the starter hole is likely crankshaft end play.
 
kbrandt said:
It shakes at all RPMs. It gets more intense as RPMs increase.

The clutch chatters a little but it's not bad. I didn't adjust the clutch fingers until after the engine was installed in the car so I don't think I did that precise a job.
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If the clutch chatter isn't bad then the housing alignment probably isn't too bad. I've spent hours sitting under these monsters shimming and filing to try and get them within the .006".

If the flywheel is off the engine its easier to adjust the fingers. I use a turned piece of round stock [ 5/8" or 3/4" whichever you prefer ] to set the height. I find that much easier.
 
It looks like I have a dead cylinder. Removing the #1 wire didn't change idle at all, where the other three had pronounced changes. There is a spark, but no combustion.

Additionally, I checked the plugs and the #1 doesn't look like it's been burning any fuel. See attached picture. #1 is the right most plug.

I'm going to have to order an adapter in order to do a compression check. In the mean time, I was thinking of checking the valve clearance. Is there something else I should check?
 

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you can approximate the compression with your thumb.
remove all the plugs
have someone turn the engine over with the crank first and see, then with the starter. with your thumb over one hole at a time and see if they are all about the same.

sorry about the bad english but youll get it
 
Hello, does plug number one fire in another cylinder? That would check if plug is either good or bad . If compression is low on one may be valve hang up if rebuilt rings should be good. Let us know what you find out.
 
Also if plug works in another cylinder, would indicate a problem with distributor ,like a bad cap .If you can borrow a known good distributor, that would rule out electrical issue.
 
gdmn852 said:
Hello, does plug number one fire in another cylinder? That would check if plug is either good or bad . If compression is low on one may be valve hang up if rebuilt rings should be good. Let us know what you find out.
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When I pulled the plugs for that picture, I purposely put them back in other cylinders. Then I pulled #1 wire while running and got zero change. The problem didn't follow the spark plug, so I'm assuming it's good.
 
gdmn852 said:
Also if plug works in another cylinder, would indicate a problem with distributor ,like a bad cap .If you can borrow a known good distributor, that would rule out electrical issue.
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The distributor cap, coil wire, coil, points and condenser are all new. I've ordered a new distributor body, as that's the only old electrical part remaining. Besides, it never hurts to have spares.
 
you should be able to "hear" lack of compression when using starter with ignition off ---or feel it using the hand crank.
You could also look down the spark plug hole and watch the valves move ,a stuck one won't go will just stay up
 
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