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| What causes cam bearings to flake apart? https://slantsix.org/forum/viewtopic.php?t=60079 |
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| Author: | shadango [ Thu Aug 25, 2016 8:16 am ] |
| Post subject: | What causes cam bearings to flake apart? |
So my son and I completed teardown of the engine last evening and got the cam out and yes, the issue was that two central cam bearings are falling apart. What causes this? I assume some lack of oil maybe at one time? But it looks like they were being chipped away at??? The cam itself shows no sign of scoring or problems....just browned/burnt some due to lack of oil when the pump siezed. 
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| Author: | slantzilla [ Thu Aug 25, 2016 8:35 am ] |
| Post subject: | Re: What causes cam bearings to flake apart? |
Quote: The cam itself shows no sign of scoring or problems....just browned/burnt some due to lack of oil when the pump siezed. |
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| Author: | Joshie225 [ Thu Aug 25, 2016 9:02 am ] |
| Post subject: | |
I've torn down quite a few Chrysler small blocks and many of them had pieces missing from the cam bearings. Honestly I think Chrysler used cheap bearings and that slants don't usually have problems with them because they are oiled very well and are relatively lightly loaded. If you put in new bearings and the cam turns freely then you're good to go. |
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| Author: | shadango [ Thu Aug 25, 2016 9:56 am ] |
| Post subject: | |
Quote: Honestly I think Chrysler used cheap bearings and that slants don't usually have problems with them because they are oiled very well and are relatively lightly loaded. If you put in new bearings and the cam turns freely then you're good to go.
Maybe, but the chunks caused the oil pump to sieze....and from what I am putting together thru my investigation, it may have happened before on this engine.....the oil pump gasket looked too damn new to be original....so MY guess is it happened before, and they just assumed it was oil pump and swapped one in....??
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| Author: | Joshie225 [ Thu Aug 25, 2016 11:54 am ] |
| Post subject: | |
If the oil pump is aluminum it's original. All the replacements are cast iron. If the flake from the cam bearing got into the oil pump then the pickup screen failed. |
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| Author: | '67 Dart 270 [ Thu Aug 25, 2016 12:14 pm ] |
| Post subject: | bearings |
I can't tell from the pic, are those cracks in the bearings or built up material? I was thinking there were bearing flakes being crushed together by the cam rotation and repressed into those ridges on the bearing surface (hot, plus no oil condition). Brian |
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| Author: | slantzilla [ Thu Aug 25, 2016 12:35 pm ] |
| Post subject: | |
I'd guess he previous owners ran it out of oil at some time, or just did not care for it well. We had a customer at the gas station I worked at who changed oil every 20,000 miles in his '74 Valiant because people told him Slants were indestructible. It made 100K before it died, then Mopars were all junk according to him. 
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| Author: | shadango [ Fri Aug 26, 2016 7:12 am ] |
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It wasnt sludged up at all inside the engine which I would expect if the oil was never changed....?? |
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| Author: | coconuteater64 [ Fri Aug 26, 2016 8:54 am ] |
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Quote: I'd guess he previous owners ran it out of oil at some time, or just did not care for it well.
Sounds like my grandfather. He never did oil changes and just topped it off when the oil got low. I inherited his cars and every one of them was full of sludge and had internal damage like collapsed lifters and broken pistons. All were under 80K miles. We had a customer at the gas station I worked at who changed oil every 20,000 miles in his '74 Valiant because people told him Slants were indestructible. It made 100K before it died, then Mopars were all junk according to him. 
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