Babbitus fragmentus!

[Synchro909]

Originally Posted by Tom Wesenberg

The best thing you can do for the life of the main bearings is use a COUNTERWEIGHTED crankshaft.

I'll second and third that. Counterweights take a lot of the load off the main bearings and make the motor run smoother. I'm already planning my next engine and counter weights WILL be done. I will not use the weld on type, rather they will be shrunk onto the crank shaft flange and bolted for extra security. After that, I will be putting an extra weight on the side of the first one, nearly doubling the amount of weight. With that crank shaft running on inserts, I expect many tens of thousands of miles out of the bottom end. Naturally, lots of weight will have to come off the flywheel to compensate.

[Tom Wesenberg]

Are you using Dan Price counterweights? I'd be careful about adding more weight because you can go too far the other way also. Ideally you want the weight on one side of the crankshaft at each point along the length to be the same as the weight directly opposite it. This isn't possible, but can be greatly improved on over the original Model A crankshaft.

The weight of the crankshaft and flywheel isn't any magic number, and the flywheel doesn't have to be lightened by 12 pounds if 12 pounds is added to the crankshaft. Also the flywheel effect will change depending on how far from center the weight is added and subtracted.

[Synchro909]

Originally Posted by Tom Wesenberg

Are you using Dan Price counterweights? I'd be careful about adding more weight because you can go too far the other way also. Ideally you want the weight on one side of the crankshaft at each point along the length to be the same as the weight directly opposite it. This isn't possible, but can be greatly improved on over the original Model A crankshaft.

The weight of the crankshaft and flywheel isn't any magic number, and the flywheel doesn't have to be lightened by 12 pounds if 12 pounds is added to the crankshaft. Also the flywheel effect will change depending on how far from center the weight is added and subtracted.

Tom. Who is Dan Price? I am not familiar with him or his counter weights. I intend making my own. It's easy to have them profile cut and bore the centres of them.
I have read on this forum that the ordinary weld on weights contribute about 40% of the ideal amount of weight for counter weights. By nearly doubling that, I figure I can get to about 70-75 % of ideal. Much closer. Can anybody confirm or otherwise this 40% figure??
I understand that 12 lb added to the crank is not the same as 12lb removed at the outer edge of the flywheel. All I want to do is keep the rotating momentum somewhere within reason.

[colin1928]

Originally Posted by Tom Wesenberg

The best thing you can do for the life of the main bearings is use a COUNTERWEIGHTED crankshaft.

Tom IMO this the 2nd best thing for main bearings
I believe the No1 force on centre main bearings is the heavy flywheel followed by flex and harmonics
No1 lighten flywheel
No2 counterweight crankshaft
No3 balance everything

[P.S.]

Chris / Ron- Here is a shot of the crank at the center bearing with the cap off and the rear. The front cap isn't off yet. I peeled the shims off since it looks like a total do-over anyway. Zero damage to the crank!

[TinCup]

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I have been running a center main taken from another car for over 5k miles. Just pulled the cap along with the front and the rear and all is good. Pulled a shim out of the center and had good wear front to back. It is just a interim solution until I can afford the full job.

[Synchro909]

Originally Posted by P.S.

Chris / Ron- Here is a shot of the crank at the center bearing with the cap off and the rear. The front cap isn't off yet. I peeled the shims off since it looks like a total do-over anyway. Zero damage to the crank!

PS, You certainly did the right thing stopping the engine as soon as you heard it complaining. Well done. You no doubt saved yourself lots of $$$

[Kurt in NJ]

One of the advantages to having Babbitt is that most likely there is no crankshaft damage from such a babbitt failure if you don't try to drive it more than a few miles after the failure----with inserts many times by the time you hear it there is crankshaft damage because the babbitt layer is thin and as soon as the shaft runs on the steel the damage is quick

From what I can see in your picture it doesn't look like there are oil wells at the parting line ---this if it is so would indicate non original babbitt

[Jeff/Illinois]

This best sums up all the talk concerning Model A Ford speeds, 40MPH--50MPH--- whatever you drive in relation to engine life.............


https://youtu.be/_VrFV5r8cs0

[Chuck Sea/Tac]

Originally Posted by Kurt in NJ

One of the advantages to having Babbitt is that most likely there is no crankshaft damage from such a babbitt failure if you don't try to drive it more than a few miles after the failure----with inserts many times by the time you hear it there is crankshaft damage because the babbitt layer is thin and as soon as the shaft runs on the steel the damage is quick

From what I can see in your picture it doesn't look like there are oil wells at the parting line ---this if it is so would indicate non original babbitt

I've heard this, and even said it, but I drove a Aerostar 25,000 with a bad rod , and my GMC van 20,000. So I don't know. I guess the actual Babbitt wasn't worn thru?

[katy]

FWIW, both the Aerostar and the GMC have pressure lubrication.

[P.S.]

Originally Posted by Kurt in NJ

From what I can see in your picture it doesn't look like there are oil wells at the parting line ---this if it is so would indicate non original babbitt

Correct!

Definitely not original babbitt. The further we tear this motor down, the more obvious it is that it has been redone in its past. The original owner is deceased, so we cannot consult him. I do have paperwork for the car dating back to WW2, but nothing before then. Nothing in the paperwork about any engine work.

Owner #2 is my friend who is an absolute expert and is taking the lead on this project. I bought the car from him in December and became owner #3.

[Gerald1961]

i recently had to go by magic metal carpet due to lost rod babbit, only on cylinder1. Any other babbitt is fine, crankshaft seems also not to be injured. I' m now not shure if i should change to modern rods with insert bearings or to rebabbit rod nr.1. Who can tell about his experiencen with inserted bearings? Will i achieve the same durability as with babbits? My engine is rebuilt 6000 mls and ca. 15 yrs ago. Please help.....thx in advance

[jfreddie]

If only the cap is bad you could get a rebabbitted cap from Bill Barlow in Bend, OR.

I've used his caps in 5 A's here in Alaska where we don't have any babbitters.

His workmanship is first rate and his prices at $50 ea are very affordable.

I like sticking with babbitt for the reason you mentioned...the babbitt failed and didn't tear up your crank.

When an insert fails, your crank will be affected and likely need grinding.

I certainly agree that counterweighting is a big help to minimize the center main wear.

Good luck.

[jfreddie]

About the rods...depends on how much $ you want to invest.

If only one rod is affected, the cheapest way is order a rebabbitted rod from Bert's.

They're the only co. that will send you a rod without a core...you can send it back later...for about $50.

If you go insert, you'll have to get a set to keep balanced. They're very nice quality and fit is quite good, but it should be for $500.

If you go inserts, make sure your crank journals are in very good shape as the bearing material can be scuffed or scored and are not forgiving like babbitt. They're harder and may wear the journal if there's any imperfections. They work best on a fresh crank regrind.

Good luck.

[Gerald1961]

Hi jfreddie!

Thank you for your quick answer!
My crankshaft is counterweighted and I want to have it regrinded definitvely. You are just expressing my opinion about inserts.

I am located in germany where I found at least 5 companies being able to rebabbitt..but there is no way to estimate the quality. Also they give me strongly varying costs, but anyway much much more than 50$...Could you please p.m. me the email adress or website from bert´s ? That would be very kind from you!

BR

Gerald from Germany

[P.S.]

UPDATE

Expert friend Bob did a motor rebuild with full inserts and the motor is installed. Have about 15 miles on the motor now, and its a champ!

I have a slow oil drip only while the motor is running. Drip appears to be coming from the intersection of the front and side timing gear covers at the top. Should be easy to fix!

As for the question about inserts.... I have insert bearings in the motors of both Model As now. Absolutely thrilled so far. Especially like the idea of no shims or periodic adjustments necessary. The bottom end is just like a modern engine now. One less thing to worry about.

[mshmodela]

Sorry to read of your babbit failure.... Makes me think whenever I have my engine rebuilt. I'll have inserts put in....

[Mitch//pa]

inserts here

[Y-Blockhead]

Originally Posted by H. L. Chauvin

Roughly how many miles were on your engine since last center main bearing adjustment?

Newbie questions... What's the recommended milage between center main bearing adjustments? Or how do you determine when you need a center main bearing adjustment?