So today I looked at the cams and lifters again. I have a couple of used r/h cams, one I believe any normal person would use again without a second thought and one that any decent engineer would not. Which isnt to say I'm thrilled to use the acceptable one but thats the life of the pedantic. I checked the new lifters for correct finish and found them all good.
The V10 engine has a reputation for being hard on lifters and valve guides so I'm paying particular attention to this area hence the preoccupation with such matters as lifter and cam profile.It doesnt help that I dont know the actual mileage of the engine originally and I also have parts from another engine of unknown mileage.
No one has a definitive answer to this issue so everything needs to be examined. The cam lobes on this engine are lubricated via a small 1mm dia hole in the camshaft between the lobes. The cam itself is housed in what could be best described as a bathtub arrangement. Oil is fed from a main head gallery into the center of the camshaft and it then squirts out of the lube hole and keeps the bathtub filled which the lobes dip into on each rotation and it also squirts a bit of oil into the general head area.
Its not a system I'm totally in love with as I'd much prefer to have the oil distributed directly to the opening ramps of each lobe, but it is what it is.
Interestingly on my unusable r/h cam I found the small 1mm oil feed hole almost totally blocked so that explains the wear I guess.
Whats really important with this engine is to make sure you have plenty of cam lube on the lobes before its first start AND the bathtub the cams sit in is filled with oil. I'm wondering if a lot of the cam and lifter issues stem from poor attention to these areas at the factory as you can toast a lifter and lobe in the first 30 seconds of operation if you haven't prepared.
Lifter faces all good. radias is something like 76 feet but they all measured up at 0.06mm across the face ctr to edge.
Here's the cam lube hole that was almost totally blocked.
Here's what was blocking it. One of the 2 pieces on the left is what I found. They were some form of organic material and I had no idea from where but in one of those crazy moments where the universe provides you with an answer from, well somewhere, I found the source. If only the universe stepped up for something really meaningful.
Not more than 5 minutes after finding the partially blocked oil feed hole ( partially blocked as in a 1mm drill needed to be pushed with force to clear it although a bright torch shined in the hole still showed a little light in the main cam gallery) I was looking at the main head gallery where the blanking plug is fitted and at the inside end of the threads I found stuck there the piece of the material shown on the right of the pieces that blocked the hole. its the thread sealant the factory used on the oil gallery blanking plug. It looks a little less translucent in the photo because it thicker in section but its the same stuff.
My wife often wonders why I'm awake thinking at 3am.
Ciao