Mike - Thanks for the info. I'm pretty sure these lifters are needle bearings. The two with the most damage turn but are rough. All of them seem to have more side play than I would expect.

Here's more info I gathered today.

Ran a magnet around in the oil that drained out (which was also what was in the oil tank) and found some metal flecks about the size of a period at the end of this sentence. The scavenge side of the oil pump has tiny nicks in the georotor. Pressure side looks almost new. That seems consistent with the damage on the lifters and cams. Wiped the bottom of the cam chest with a rag and no metal. If anything was there it probably ran out with the oil.

I removed the oil pressure relief valve. Slid right out with a little tapping on the cam plate. It has a couple of polished spots from movement which I would expect but no scarring like from foreign objects. I flushed out the passage with WD40 and no metal or trash.

Inner cam bearings look and feel fine. No missing rollers and turn easily with the tip of my finger. Wear patterns on all bearing surfaces on the cams and cam plate look normal.

It's a puzzlement how that damage is there and everything around it is okay.

Does anyone know if that pipe plug on the bottom of the crankcase can be removed without damaging the case or creating an oil leak. Probably a good idea to see what's in there.

 

Damage to the scavenge section is what I would expect.
Needle bearing are kinda fragile things. I think the needles in the lifters simply disintegrated.

I think the logical course of action would be to get as much oil out as you can, clean the tank and replace the cam bearings while you have it apart. It only takes a tiny piece of trash to mess 'em up. Notice the "skid mark" on one of the lifters.

Once you get 'er back together, run the motor for an hour or so, and change the oil and filter again. Change it again at several hundred miles.

 

Gordon I read horror stories about removing that plug. Some guys get it out and back in ok, some guys break the case which is an obvious huge problem. I understand it's not intended to be removed.

 

Thanks, Mike.

Joe - I agree on the plug. They weren't meant to be removed.

I had changed the oil right before the trip to FL last month and drained the oil and inspected the filter right after the trip. The oil that came out the other day is fresh (plus whatever was in the engine). I suspect most of the trash has been flushed out. A couple of quick changes should take care of anything else. I didn't find as much metal as I would have expected with the damage.

 

Sounds fairly reasonable.

Just keep in mind these two little words when dealing with componentry such as this.....

Assume nothing.

 

My friend in the failure analysis business has an initial thought of improper heat treat. But, he only gave it a cursory review until he has time this weekend.

 

Tom from AMS made a house call today. Inspected and measured everything for clearances, etc, etc. Nothing out of the ordinary and good by what he's seen on HD over the years. Bearing journals on the cams were perfectly round.

The only thing unknown is how the new lifters fit in the bores and how well the anti-rotation pin holds them in place. Don't have the new ones yet. There was some evidence of two of the lifters chattering in the bores and on the pin. Pins are okay but there was wear where the pin rides. Pin is harder than the lifters.

He did a hardness test on the lifter rollers and cams. Two of the cam lobes failed the test. Appears that the heat treat wore through which accelerated the wear (the chattering may have contributed to that), then the metal flaking off gets in the lifter rollers, then they don't roll, then that causes more problems. I feel better knowing what caused the problem. I was hesitant to put stuff back together without knowing.

Tom works on a lot of Harleys and had only seen the heat treat problem one other time on an Andrews cam.

By the way, the one lifter that looked like it had two chunks missing next to the roller was just trash. There was no metal missing there.

The front cam bore on the cam plate was a little out of round giving .0033 clearance which Tom says is enough to loose a little oil pressure at idle and make ticking noises. There was some wear you could only see with a magnifier. The original machining marks were gone in about a 45* arc in the bore. Not excessive wear now but he said it will get progressively worse with time. He suggested replacing the cam plate. Oil pump is good.

He found some evidence of oil leaking around the passages between the cam plate and crankcase which would loose oil pressure to the lifter galleries at idle. Tom machines oring grooves in the cam plate to solve this problem.

Tom suggested replacing the hyd cam tensioner shoes with Cyco replacements. Now that I can see the face of the shoe, there is a little bit of chipping where the chain runs. Cyco has a different material that doesn't chip. It's a direct replacement for the HD shoe. Keep in mind this is after 58K miles with about 1/64" of wear. I'm only doing this since I'm already in there. You don't need to worry about the hyd tensioners for a LONG time.

 

Good to know
And glad your getting great help

 

All parts are here and it will run tomorrow! I had the cam plate machined for orings to stop the small oil leaks around five of the oil ports.

 

GTMalone we appreciate you bringing us along on your repair travels.

How did the cam plate look where the cams run without bearings in your hybrid hydraulic solution? I've heard people complain that there are no roller bearings on the new cam plate vs the roller bearings on the spring loaded follower cam plates.