Main bearings, here I come

[MikeMort]

Have spent the past few days lying on my back as I wanted to see if I could find the reason for that knocking sound in my engine bottom half that is by now loud enough to be commented by wife, daughter and the family dog.

However, having torn the car half apart already in order to get to the center main, some questions now arise in my mind:

1. How do you get to losen the outside nut on the center main bearing bolt without removing the water outlet (and the hose, the tube and the generator also now you are there?)
2. How do you get to the nut in the valve compartment without removing the distributor/oil pump gear (as I have now done, meaning that I have to retime the engine later)
3. Bolts should be torqued to at least 75 foot pounds they say, but how do you fit a torque wrench on these nuts? - mine certainly will not get into the valve compartment, or fit up agains the cylinders.
4. How do you, working entirely on your own, wife, daughter (or dog) as usual not around to help me out of this oily mess, hold on to the bottom square head of the center bolts from the underside f the car, while at the same time standing beside the car, leaning over that stupid front fender in order to apply maximum force to the nuts?
It all sounded so easy in that manual, they don't mentioned any of this.
Oh, by the way: should I get that center bearing undone only to discover that there is way to much clearance on it, is it then OK to grind or file a little off the mating surface in order to tighten it up? I seem to remember that there wasn't any shims there when I assemled the engine a couple of years ago.

 

[1930artdeco]

Hi Mike,

If you have that much torn apart it is easier to just pull the engine out. Other wise you are on your back and oil is dripping in your face.

2) Take everything out. IT will make your life so much easier.
3) you may ahve to use an offset with a crows foot. That changes how you calc. the torque, i just don't rmember how to calc. it that way. Are you useing cotter pins or the new lock nuts?
4) Pull the engine and put it on a bench or stand.

Mike

 

[Duffy1]

pull the engine as 1930 artdeco suggested.If there are no shims left you are probaly near the end as it relates to the life of the main babbits.

 

[Mike V. Florida]

...

Have spent the past few days lying on my back as I wanted to see if I could find the reason for that knocking sound in my engine bottom half that is by now loud enough to be commented by wife, daughter and the family dog.

However, having torn the car half apart already in order to get to the center main, some questions now arise in my mind:

1. How do you get to losen the outside nut on the center main bearing bolt without removing the water outlet (and the hose, the tube and the generator also now you are there?) Socket with a universal joint.

2. How do you get to the nut in the valve compartment without removing the distributor/oil pump gear (as I have now done, meaning that I have to retime the engine later) Box wrench

3. Bolts should be torqued to at least 75 foot pounds they say, but how do you fit a torque wrench on these nuts? - mine certainly will not get into the valve compartment, or fit up agains the cylinders. Use torque wrench on the bolt head not the nut.


4. How do you, working entirely on your own, wife, daughter (or dog) as usual not around to help me out of this oily mess, hold on to the bottom square head of the center bolts from the underside f the car, while at the same time standing beside the car, leaning over that stupid front fender in order to apply maximum force to the nuts? Box wrenches and use torque wrench on the bolt head not the nut.

It all sounded so easy in that manual, they don't mentioned any of this.
Oh, by the way: should I get that center bearing undone only to discover that there is way to much clearance on it, is it then OK to grind or file a little off the mating surface in order to tighten it up? This would be a temporary fix until you can get the money to do it right.

I seem to remember that there wasn't any shims there when I assemled the engine a couple of years ago. Get money together to do it right.

 

[glenn in camino]

It's all a lot easier on an engine stand.

 

[Phil]

It would be easier on an engine stand. Buts it is a lot of work to pull and reinstall the engine.
1 get a eight point socket to fit the square heads at the main cap. Then just a box end to hold het nuts on top.

2 if the Babbitt is ok, you probably have shims that can be removed to get the .0015 clearance .

3 I torque main bolts to 55 lbs.

It is a job that very doable. You can get very good results. And have a good reliable motor for many miles. They were designed to be maintained this way. Good luck and ask any questions you need.

 

[columbiA]

Inthe early 50,s I did an in-frame o-haul on my 1,st A.I did rings ,valves & brg adj &had no problems.In those days you only pulled the engine if it needed rebabbitting.Even cyl reboring was often done in the car.

 

[PC/SR]

I agree with Mike V, except just take off the water inlet (not outlet) to get to the outside center main nut. No need to remove the rest of it. Its just two bolts and a hose clamp. And remove the distributor drive gear to get to the inside bolt, as you have done, although if you do not move the crankshaft at all, and put everything back exactly the way it was you do not need to retime it. But retiming should be done anyway. If you have no shims you need to rebabbitt, which is probably why it failed in a "couple of years." It is telling you something. Check the other bearings as well.
As for the rest, the wife and dog (no daughter) have never helped me either but I got through it without 'em. But at least the dog kisses me when I am greasy.

 

[Kurt in NJ]

There are "special tools" that were made for mechanics to make the job easy, and give a reasonable tightening ---the length of the tool when used to get the bolt "good and tight" would create a reasonable "torque", and it is angled to have acess to the rear main nuts in the chassis.

If you look closely at the square head of the main bolts you will see a small nub on one corner, it is to help with lining up the cotter pin hole.

 

[redmodelt]

Mains should be around 75-80 which is just about what the proper wrench gives with a good steady pull. If you need to pull more then that to line up to put the cotter pin in then remove the nut and grind a little off the bottom of it. Don't go over board with the grinding, most of the time it only takes a little.