4th Main Alignment

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ArthurB
Posts: 77
Joined: Wed Jan 09, 2019 5:22 pm
First Name: Arthur
Last Name: Babitz
* REQUIRED* Type and Year of Model Ts owned: 1927ish Roadster Pickup
Location: Hood River, Oregon
Board Member Since: 2018

4th Main Alignment

Post by ArthurB » Tue Jun 23, 2020 3:14 am

I am installing a newly babbitted 4th main on a 1926 engine. It fits the shaft like a glove. The Ford manual and Chaffin book both say to adjust the alignment with shims between the hogshead and crankcase. Sure enough, with a little pressure on a prybar behind the hogshead it slides into alignment. My question: Is there any recommendation about where to place the shims, or what size/shape shims to use? It seems like with all the vibration you would want some sort of retention, like putting a thin washer behind the bolts, but the diagram in the manual just points to the general area near the top of the hogshead. I'm sure this is obvious, but not to me!


Kerry
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Re: 4th Main Alignment

Post by Kerry » Tue Jun 23, 2020 4:33 am

It's simple enough, shims or flat washers to fill the gap between the hogs head and block at the 2 bolts at the top, if you need to pry it any. Usually nothing is required. If your ball cap is sliding ok and sits flush on hogs and pan, gasket between, then bolt it all up, no gasket on the drive shaft side.


Adam
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Re: 4th Main Alignment

Post by Adam » Tue Jun 23, 2020 9:47 am

Use the brass laminated magneto field coil shims between the block and hogshead. You might have to make the hole in the shim bigger.


Dan McEachern
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Re: 4th Main Alignment

Post by Dan McEachern » Tue Jun 23, 2020 11:23 am

Also, laminated Model A connecting rod shims work nicely for this purpose.


Scott_Conger
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Re: 4th Main Alignment

Post by Scott_Conger » Tue Jun 23, 2020 12:14 pm

Dan

that's a great tip
Scott Conger

Tyranny under the guise of law is still Tyranny

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