The MoCo introduced the Long Block program at their last Dealer's meeting. The program was launched in part as a resolution to the noisy lifter problems that have plagued some owners whose bike is still under warranty. Here are the details leading up to my new Long Block.
I own a 2013 FLHTK. It currently has about 35k miles on it. Options include Rheinhardt 4" slip-ons, high flow air filter, 255 cams and a Super Tuner.

At 5k I started noticing some lifter peck at cold start-up. It gradually got worse to a point where the peck continued for 45-60 seconds before it started to diminish. Once the motor warmed up the lifters were quite. At just under 10K the MoCo ok'ed lifter replacement.

That fixed the problem for about 4-5K miles. Then it started returning. Gradual at first but getting more and more noisy and they took more time to pump up. I had been reading about HD lifters being pretty bad so I approached the dealer about using aftermarket lifters. I was surprised to hear the MoCo approved the labor to install the aftermarkets lifters. I selected AMS lifters. The rocker arms were found to be way out of spec. so we used shims from AMS to get them within HD tolerances. The shims made a ton of difference in top end noise and I was very pleased at how quiet the motor ran. The mechanic said it sounds like a "sewing machine". But shortly after their installation, the cold start pecking was back.

AMS immediately sent a new set of lifters when I reported the problem. I bought a set of adjustable push rods so the labor to install the new lifters would be less expensive.
Within a few hundred miles, the pecking was back with a vengeance but this time it did not fade away after the motor warmed up. I suspected a lifter had a total failure and while the guys at AMS doubted my thought, they sent a new set of lifters. When the mechanic tore into to it, he found a push rod was broken due to a manufactuers defect. New push rods and a new set of lifters went in. This was the fifth set of lifters.

I took off on a Road Trip of nearly 7,000 miles. The peck returned just as before. The trip was during the start-up of Sturgis week and a lot of the hotels we stayed in had a lot full of parked Harleys. I had a lot of conversations with other riders about my issue. I listened to a lot of cold starts on other bikes and a lot of riders listened to my bike startup. (Usually very curious, technical guys.) They all agreed there was a major problem with the motor. As I returned home, the noise got worse. It was louder and now was evident when starting it after lunch and sometimes after getting gas where it was shut off for less than 5 minutes. After letting it idle for a few minutes it would quiet down.

I thought about my approach on getting the problem fixed. I was convinced the lifters were bleeding down but not sure why. The lifter bores had been measured and were good. The oil pressure was considered to be a little better than most HD engines by a couple of pounds.So, when I got home, I took the bike in with instructions to the Service Director that I wanted him to ride it for a few days. Take it home, to lunch, to chase parts, whatever he did and needed transportation, just take my bike. That convinced him we needed to take a radical course of action. He called HD and went to an upper level technician. This was apparently easy due to the number of times the bike had been in for the problem. The technician told him it sounded like a common failure they have been seeing. The problem is with a valve that controls oil flow to tubes (maybe nozzles) that spray oil on the bottom of the pistons. He speculated there was a failure which allows the oil to bleed off from the lifters. This failure also causes oil starvation and prematurley wears internal components. It was for the latter reason that the MoCo sent a new long block which has been installed on my bike and has about 600 miles on it.

Apparently, I am not the only one with the same problem. I am hearing about other guys that have gotten the same resolution from the MoCo.

 

Can you be more specific? What "valve" is the tech referring to that controls oil flow to the piston cooling jets? AFAIK, oil flow to the piston oilers is controlled by passages in the cam plate/chest and the internal valving in the jets themselves control flow by not opening until pressure reaches 15psi.

Not doubting what the tech says, just trying to understand what he says. BTW, glad you finally found a solution.

 

I wish I was technical enough to give you the answer but I am not. I am repeating what the Service Director at my dealership told me.
He did say it was directly related to the oil flow with the lifters.

 

Here is a copy/paste of an Email sent to me by Tom at AMS in Texas. Apparently, he is aware this can be the cause. This was sent to me before the MoCo tech mentioned it as an issue. Maybe it will help explain the problem.

"A defective piston oil cooling jet. The jets are fed oil from the same passage that feed oil to lifters. At low rpms & when the engine is off, they're supposed to seal of to prevent oil loss to the lifters and/or prevent oil from draining out of the PR / lifters."

 

OK, that's what I thought. If the problem is a defective piston oil cooling jet, why is a long block required to address the issue? Why not just replace the oil cooling jets?

 

I am not sure. But I am not the only one to get a new motor so I assume there is a reason. I mean we all know the MoCo does not pay nay more than they have too, right?

 

Amen brother. I am just trying to unravel the mystery of your situation. If oil cooler jets are defective and open at less than the design 15psi, that would certainly contribute to lifter bleed down at idle and low rpm. So, the mystery, for me anyway, is why a long block to solve that problem? Anyway, glad you finally solve the problem solved.

 

If all the oil left the lifters and I assume the push rod tubes and it takes up to a minute for enough oil and pressure to pump them back up, what moving parts would be dry of oil during that minute? I have no idea but I assumed that is why they replaced the motor.

 

That's the mystery for me. I the piston oil cooler jets are closed when pressure drops to or below 15psi, there should be no oil "loss". That's why one would think that replacing the cooling jets would be the solution vs a long block. Therein lies the mystery that peaks my curiosity. The moving parts involved would be the valve train which is the clatter you hear on start up that goes away as the motor warms up. I guess it will remain a mystery!