Technical Flathead Main Bearing Cap

Yesterday was a bad luck day! I had purchased a 1950 Mercury Flathead engine that was to have only 500 + or - miles on it after rebuild. The engine came in a 1931 Ford project car. I removed the oil pan for cleaning, painting and was in the process of replacing the gaskets. I did not like the looks of the upper rear main gasket and decided to loosen the main bearing caps and replace. When I got to the center bearing one of the bolts were broken and the cap was also broken. I am very lucky I removed the pan and checked the internals. I have been searching for a new center main cap with no luck. The casting identification is: 7RA-6339. What would be a good source to secure this cap? The next problem is to remove the broken bolt from the block. I will have the engine machine shop line bore the block and bearing caps and I hope he can remove the broken bolt.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

Thanks for any help or advise!
Ray
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To view the 1931 Ford, click on the link below and then click on the hot rod picture
www.rayscorvette.com

I have posted this tread on other forums

 

Just get a cap off a junk 8BA style block.

 

The man that machines my V8&#8217;s and knows them well has found that it possible to find caps that require little to no machining to fit on a block they didn&#8217;t come on.
The key obviously if get a few of them to try.

The bolt shouldn&#8217;t be bottomed so&#8230;the remaining should be lose.

 

Yep That's been my experience also.

 

Sadly, I detect a line-bore in your future. If you had a dozen caps to choose from you might get one that lines up properly.

 

Thanks for all the help!

Ray

 

I have a set of 8BA caps that I will sell for a reasonable price. Feel free to pm me.

 

Thanks, Email mail me at: [email protected] with your address and I will send payment for the center main caps.

Ray

 

I goofed!!!

Center main bearing cab should be: 7RA-6330 not 7RA-6339 that I had listed in an earlier post.

Thanks for all the help!! Ray

 

I'm sending ya a whole set.....use em if ya need em!

 

turn engine upside down and mig weld a nut onto the remains of the bolt. The heat loosens the bolt and then you have something to grab onto. If you are a poor welder like me and the nut comes off just keep repeating till you get it.

 

Uh, I would look real close at the web and make sure it isn't cracked, broken cap and bolt could mean more damage...........

 

If you find you must weld something on to the broken end, use a bigger washer first.
Size the hole in the washer to be a tad smaller than the bolt diameter if the bolt is flush...otherwise just use one that fits directly over the nub.
It's thin so you can get access to get a good deep weld into the bolt.
Then weld a nut onto the washer by welding around the nut.
Again, good penetration.

I've had much more success doing it like that then just trying to weld down inside the relatively deep hole inside a nut.

 

Hackerbilt is very right. And if the nut or washer you are useing is anodizsed or galvanized grind it clean before you weld.

 

As long as it's going to the machine shop for line boring, have 'em remove the broken one, if it isn't siezed in the block.

4TTRUK

 

Roseville Carl.....Good thought !!!!

4TTRUK (Citrus Hts.)

 

If you do need to line bore your machine shop may have an issue they don&#8217;t want to deal with when it comes to cutting the caps.

My buddy has built the setup to cut them&#8230;.I can put your together with him if need be.

 

You guys are GREAT! I should have three or four center caps in the mail. Hopefully one will match up and we can get the flathead back together and move on to another part of the hotrod project. I have contacted the engine machine shop that has done all my engine work in the past and will be taking it to his shop as soon as the bearing caps arrive. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
If you would like to see the broken bolt and cap, please click on the link below and scroll to the bottom of the page: www.rayscorvette.com
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Merry Christmas to all!

Ray<o></o>

 

I Finlay got the 1950 Mercury flathead back from the engine shop! Thanks to everyone that has provided me with help and the main bearing caps! I now have a good selection of main caps, (complete set and center caps) if anyone is in need of caps for the price of shipping, I only ask that the caps you do not use get passed on to another person in need; email me at: [email protected]

Thaks for all the help!

Ray