I would have assumed so but the product pictures shows copper. It should be here this week, will let you know.
As far as the wear Cummins inspection instructions shows that any heavy scoring the bearing should be replaced.
I would have assumed so but the product pictures shows copper. It should be here this week, will let you know.With the cam bearing do they normally have a Babbit layer over the Copper?
Apart from no layer there does not appear to be much sign of major wear, only a couple of wear points.
Thanks, I have the 3901306 bushing on order.With the 2 large freeze plugs you definitely have the early block. Yours would be bushing 3901306. As for the construction of that bushing it seems to vary depending on who makes it. Some are definitely babbitt coated and some appear to be a copper colored coating. Don't think it would be regular copper though. Probably a special alloy that has a copper tint. Clevite's bushing is one of the copper colored ones and is their part SH-1404. Prices on that part range all over the board. From about $5 to over $60. The ones in the genuine Cummins box range from about $30 to the $60+ range. Below are 2 photos, both of a Clevite SH-1404 and their surface appears to be totally different.
bad tappets i would believe and likely bad tappet holes.. ... check the tappets and holes to make sure they are in spec. if the tappet holes are too larger the tappet can walk and do funny things to the cam ( think of them as orbital sanders.. )The Cummins repair manual doesn't say any thing about the patterns on the cam lobe. Anyone seen this before? I still need to pull the lifters to see their condition.
Cam Wobble side to side could cause the tappet patterns... I would suspect..The tappets holes and tappets are with in spec.
But the "clown" that installed the cam bearing didn't get the 2 holes lined up. According to the Cummins spec that's a no-no. Almost half of the oil hole is covered by the bearing.
I guess it's A new number for the books:Yup, I'd found a photo that showed the part number there. Well, it may be a casting number but anyway it's a way to identify it. Incorrectly installed cam bushing would sure account for premature wear. Lucky you caught that before it damaged the cam. One thing that has me puzzled. You listed the cam as part 3924574. What little info I could find says this is a 6bt cam and Cummins shows it obsolete with no replacement number.
Camshaft end play is withing spec.Cam Wobble side to side could cause the tappet patterns... I would suspect..
are the cam journel holes in spec or out of round?Camshaft end play is withing spec.
I'll be checking that today as best I can do with a digital vernier caliper.are the cam journel holes in spec or out of round?
Now was that so hard,,,The tappets holes and tappets are with in spec.
But the "clown" that installed the cam bearing didn't get the 2 holes lined up. According to the Cummins spec that's a no-no. Almost half of the oil hole is covered by the bearing.
did you check the bore for the cam?... I forgot to mention that part..Now was that so hard,,,
Not yet. The 2 to 3 inch micrometer hasn't arrived yet.did you check the bore for the cam?... I forgot to mention that part..
Yes I have a complete set of Rod and Main bearings coming (standard) and have a set of Cummins rod bolts. The ARP rod bolts were out of stock.Not a very common thing on these engines for the cam bores to be worn. You certainly want to install new rod and main bearings since you've got it apart. Those bearings a very cheap. Also, put in new rod bolts. Cummins does not recommend reusing those. They aren't expensive either. If you desire an upgrade, you can use ARP rod bolts. They are ARP part 247-6304 for a set of 8. Cummins part is 3900919 for one.