Opinions requested from Engine Builders
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,431
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From: Florida
Opinions requested from Engine Builders
I wanted to ask the opinions of those who see this stuff more often than I do. I've only built a handful of engines.
This is a new Motown Lite Aluminum SBC I just received, "race prepped".
My question is: What do you think of the cam bearings? They look like someone took 320 grit emery to them, some worse than others, front worst of all (see pics). Is this normal/acceptable? It almost looks like they did their line hone after instead of before.
Thanks,
Jim
This is a new Motown Lite Aluminum SBC I just received, "race prepped".
My question is: What do you think of the cam bearings? They look like someone took 320 grit emery to them, some worse than others, front worst of all (see pics). Is this normal/acceptable? It almost looks like they did their line hone after instead of before.
Thanks,
Jim
Tech Contributor
Joined: Aug 1999
Posts: 15,154
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From: Connecticut, USA
Hey Jim
I tried to contact you a while ago and thought you were gone. Glad to see you back.
It does look like they were dressed a little bit. Nothing like the bearing in Kevin's block where the guy left a .030 burr and the cam didn't fit. How does the cam fit?
I tried to contact you a while ago and thought you were gone. Glad to see you back.
It does look like they were dressed a little bit. Nothing like the bearing in Kevin's block where the guy left a .030 burr and the cam didn't fit. How does the cam fit?
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Block is 
. Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
. Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
Block is . Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
. Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
Those bearings look horrible.
Le Mans Master
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St. Jude Donor '11, '17
Perhaps they are trash bearings that are in there just to protect the machined surfaces. My GMPP 383 block came in with cam bearing that looked like they were install with a hammer & screwdriver. I didn't expect cam bearings anyway so I had already purchased quality bearings and had them installed during my clearancing.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,431
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From: Florida
Cam fits fine.....thanks to their butchering my bushings.
BTW...glad to hear you may get a check from that rip-off shop.
Originally Posted by 63mako
Block is . Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
Originally Posted by Gordonm
Those bearings look horrible.
That's what I thought
Originally Posted by ratflinger
Perhaps they are trash bearings that are in there just to protect the machined surfaces. My GMPP 383 block came in with cam bearing that looked like they were install with a hammer & screwdriver. I didn't expect cam bearings anyway so I had already purchased quality bearings and had them installed during my clearancing.
Thanks for taking a look guys.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
No, it's part of their "race prep" package. Sad part is I told the sales guy that I'd read a post on a forum where someone else had scratched cam bearings that World replaced and warned them I'd be on the look out for them and still got 'em. Guess that didn't work.
Thanks for taking a look guys.
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Le Mans Master
Joined: Dec 2006
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Block is . Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
. Cam bearings look HORRIBLE!!! I would e-mail those pictures to the place that sold you the block and ask them WTF!!!I would also have everything else checked either by yourself if you have the proper tools and knowledge or a reputable machine shop. If that is how they sent out the cam bearings check it all!!
If so use it now and get a new one.
Thread Starter
Melting Slicks
Joined: May 2002
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From: Florida
Le Mans Master
Joined: Dec 2003
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From: Fremont CA
Back in the day when I was a "Mopar Dude", we had problems with RB series motors (426, 440 blocks) and core shift. Every once in a while, you would get a block with misaligned cam bearing bores and have to scrape or sand the bearing bores (sometimes you had to get special sized cam bearings) to get a camshaft to fit into the block and spin freely. It looks to me like there was shift in your cam bores and someone tried to straighten out the problem, if the clearances get too big oil pressure can be low. I would have a serious talk with the seller of this engine block if you paid full price for it.
Thread Starter
Melting Slicks
Joined: May 2002
Posts: 2,431
Likes: 52
From: Florida
Update
Back in the day when I was a "Mopar Dude", we had problems with RB series motors (426, 440 blocks) and core shift. Every once in a while, you would get a block with misaligned cam bearing bores and have to scrape or sand the bearing bores (sometimes you had to get special sized cam bearings) to get a camshaft to fit into the block and spin freely. It looks to me like there was shift in your cam bores and someone tried to straighten out the problem, if the clearances get too big oil pressure can be low. I would have a serious talk with the seller of this engine block if you paid full price for it.
UPDATE: World Products has offered to send me new bearings and pay a machine shop to install them. The quote I received from a machine shop was $25 to remove and install the bearings. Seems low to me but that's what they said.
I want to thank you guys again for your time and opinions.
Best regards,
Jim
Le Mans Master
Joined: Apr 1999
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From: Raleigh North Carolina
There are two primary types of cam bearing installation tools.
One of them involves using a hammer. The bearings are mounted in a mandrel, and the hammer pounds the mandrel/bearings in.... about $125, the other uses a threaded rod & pulls them in... $600.
If you use the hammer tool on relatively soft cam bearings, they mushroom and distort -sometimes- making it impossible to install the cam. When this happens, the "operator" must hack away at the cam bearings to get the cam to go in. The bearing damage I see in those photo's looks exactly like they used the $125 tool with repeated insertion damage attempts until the cam slid in.
That would be my guess.
But since I wasn't there, take it with a grain of salt.
One of them involves using a hammer. The bearings are mounted in a mandrel, and the hammer pounds the mandrel/bearings in.... about $125, the other uses a threaded rod & pulls them in... $600.
If you use the hammer tool on relatively soft cam bearings, they mushroom and distort -sometimes- making it impossible to install the cam. When this happens, the "operator" must hack away at the cam bearings to get the cam to go in. The bearing damage I see in those photo's looks exactly like they used the $125 tool with repeated insertion damage attempts until the cam slid in.
That would be my guess.
But since I wasn't there, take it with a grain of salt.
Last edited by Tom454; Feb 6, 2007 at 04:30 PM. Reason: typo
