6BT210 Cracked Rocker Arm Assembly

[mattreigle]

I have a 6BT210 CPL 742 with about 3000 hours since a minor rebuild (new head, new injectors, rebuilt fuel pump, etc.)

A week ago I noticed a slight oil leak coming from #2 valve cover.  I decided to tighten the valve cover bolt a little (about 1/8 turn) hoping it would solve the oil leak problem.  I think I overtigtened that bolt. 

About 30 minutes from the dock on our last trip, I go to increase the RPMs to 2000 and noticed I could only get 1800, so I immediately slowed down to idle to see what was going on.

Opened engine box lid and noticed oil everywhere because the #2 valve cover bolt was missing.  I immediately turned the engine off almost simultaneously with the oil pressure alarm sounding.

When I removed the valve cover, I noticed the rocker arm assembly to be cracked in half where the bolt is (see pics).

In the best case scenario, can I just replace the rocker arm assembly and put new seals it hope it’s all good?  

If so, what is the part # for the rocker arm assembly?

Or do I need to pull the head and check anything else?  

 The only damage I can see is the crack you can see in the pic.  It looks like a clean break and I do not see any metal shavings or fragments anywhere.  Engine was running OK when I turned it off except for the loss of power.

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[mattreigle]

Update to my post

I took the rocker arm assembly off by removing the head bolt. The smaller 8mm bolt snapped off flush with the head so I will have to extract it.   I don’t see any damage to the head and the push rods look straight. Hoping i can put a new rocker assembly on with a new head bolt and it’s good. 

 

There is a small piece of metal missing (see pics) which could have ended up in tappet cover/oil pan. Does this mean I have to pull the tapper cover and pan now. It large enough I don’t think it would go thru screen on oil pump.

[mattreigle]

Another pic

Another pic…

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