About 1,200 miles ago I rebuild the engine in my 03 DII. Sleeved block done by a reputable shop, milled heads flat, new pistons, new cam, new lifter, new timing set, oil pump etc.. Crank was ground .010 under on main and rod journals, new .010 over bearings, clearances checked, new rod bolts, new head bolts, upgraded head gaskets, and all tq procedures followed to the RAVE. I checked the preload on the lifters after having the heads milled and shimmed the rockers .015 to bring everything within specification. I disassembled the heads, lapped the valves, cleaned everything up and installed new valve seals. Installed new flex plate as well. Now to the issues..

Ever since the rebuild I've had a slight knock. As best as I can tell it's coming from the valley where the cam and lifters are. You don't hear upon initial start but as the idle settles its starts to slowly build. It seems to be worse under acceleration or when revving the engine. Out of frustration I decided to drive it anyway in hopes that if it was a lifter it would pump up. After 500ish miles I changed the oil and went with a premium Amsoil in the thickest recommended viscosity. Noise didn't change but yes I kept driving. I have also had to keep adding coolant to the reservior. At first I chalked it up to bubbles in the system but after 1200 miles on the new engine I still have to top it off every 500 or so miles. I do not see any leaks externally, no bubbles in the holding tank, oil isn't milky in the pan, and no condensation out of the tail pipe.

All this brings me to today when I finally decided it was time to investigate the knocking. It hasn't changed since day one but when I checked the oil the other day it had a black residue on one side of the dipstick. When I wiped it with a rag and ran a magnet over the oil I got some ferrous pieces. I pulled the valve covers and while the oil in the head was clean, the tops of the inside of the valve covers had milky oil buildup. I expect some of this as a byproduct of the engine breathing, this seemed abnormally high for only 1200ish miles. I rotated the engine over by hand checking for loose rockers and I applied pressure to the pushrod side of the rockers and didn't note any play like a flat lifter. Felt like it had even compression on all cylinders as well. Everything seems fine....

Any other thoughts of what to check before I proceed with pulling the cam?

 

 

I think you have a major issue. Do the taste test on milky build-up...touch a drop to your tonge...if it's sweet(like antifreeze), then there is a coolant leak into oil....

 

just saw your pics...that is not good.....cracked head or block? head gasket? intake gasket leak (some don't fit well) . this is something that will require a full teardown and a check of all parts...

 

Well anything is possible at this point. I'll pull the plugs now to see if there are signs of steam cleaning of the cylinders.

 

one more thought...new liners installed...were they with the O rings?

 

they are the top hat style but no o-rings

 

That's going to be my #1 issue. Hopefully, it's not a liner leak...

 

All the plugs look good and the same for each cylinder. I’ll get my bore scope this evening and take a peak tonight.

 

Well then probably not a top end leak....which makes me think the coolant is coming out the botton of the cylinder sleeves....

PS: hope I am wrong!