HarleyTechTalk

I would like some practical advice to possibly keep me from wasting money.  My bike was on the dyno March 13, 2025 for a refreshed 117" build engine break-in and tuning.  While on the dyno, one Feuling Race lifter failed. Total dyno mileage was about 75 miles.  The lifter collapsed and stuck about 0.070" under the lifter retaining clip.  The other three lifters appear to be good.  Rollers on all four lifters still look like new.  No cam damage or other damage occurred.

Feuling is replacing the one failed lifter under warranty.  My question is; would it be wise to replace the other three lifters?  Feuling told me no need to replace the three good lifters as they only have about 75 miles on them and no other damage occurred.  Although I agree with Feuling, I have a nagging thought that I should replace the other three for prevention, which could just be an unnecessary cost.

117" Build:  2002 Road King, Darkhorse 4 3/8" Man-O-War Crank, Mega-Flo heads, S&S Cylinders, CP FT Pistons, T-Man 590PS Cam, HPI 58mm TB, Fuel Moto RTX 2-1, Fueling Race Series Hydraulic Lifters #4052: Oversize +.0015 OD

I agree with Fueling, one failed, the other three are no different than the new ones that you would replace them with.  Now if you had metal fragments then it would be different. 

R&R the one, and verify what failed inside the one is the only issue. I've had one break the metering disc- just bad luck. Replaced it, and it's been OK/on the road for years now.

I agree with Calif Phil and rigidthumper. And since you're there already, I would inspect the other three for any visual issues, and that the piston moves freely once bled down in the remaining three.

Quote from: rigidthumper on March 15, 2025, 08:42:17 AMR&R the one, and verify what failed inside the one is the only issue. I've had one break the metering disc- just bad luck. Replaced it, and it's been OK/on the road for years now.

Normally I would disassemble and inspect the lifter. However, Fueling requested the failed lifter back and is providing a return label for the lifter when they ship the replacement lifter. 

I can't help thinking about the most likely cause of a collapsed lifter in a fresh engine would be metal contaminated oil.  Even after paying attention to "operating room conditions " during and after machine work and assembly is critical. A known good safety practice is heat cycle with a lighter weight oil including oil changes early accelerated oil changes meant to capture and remove any trapped debris. 

It is known that hydraulic lifters are superb filters because they let debris in but not out.  My guess is that's what happened. They will fail (stick) like yours. You may want to consider spending a few extra dollars for something like 10/40 Shell Rotella T and even though you have started the break-in process, do some good heat cycles and a filter change before going any further.  Many builders will heat cycle and change, then go 50 miles and change, then 200.  Cheap insurance.  There's worse places for contaminated oil to get to in a new engine. 

Quote from: kd on March 15, 2025, 09:37:23 AMI can't help thinking about the most likely cause of a collapsed lifter in a fresh engine would be metal contaminated oil.  Even after paying attention to "operating room conditions " during and after machine work and assembly is critical. A known good safety practice is heat cycle with a lighter weight oil including oil changes early accelerated oil changes meant to capture and remove any trapped debris. 

It is known that hydraulic lifters are superb filters because they let debris in but not out.  My guess is that's what happened. They will fail (stick) like yours. You may want to consider spending a few extra dollars for something like 10/40 Shell Rotella T and even though you have started the break-in process, do some good heat cycles and a filter change before going any further.  Many builders will heat cycle and change, then go 50 miles and change, then 200.  Cheap insurance.  There's worse places for contaminated oil to get to in a new engine. 

I agree with frequent early oil changes and heat cycle. And thorough cleaning of all parts.  One oil change done after my heat cycle and one oil change done after 75 miles from being on the dyno. 

As part of my break-in process:  Filled with Amsoil conventional 30W break-in oil.
I heat cycled per Axtell instruction.  With large industrial fan blowing on engine.

Engine had a previous 117" tune in it completed by Doc's Performance tuning in Clermont, FL in May 2022.  This 117" refresh was with a different set of heads, cams, flat top pistons versus dished and larger TB and the new Feuling lifters.

Ran engine 30 second / shut off / cool down
Ran engine 1 min / shut off / cool down
Ran engine 1.5 min / shut off / cool down
Ran engine 2.0 min / shut off / cool down
Ran engine 2.5 min / shut off / cool down
Ran engine 3.0 min / shut off / cool down
Ran engine 3.5 min / shut off / cool down
Ran engine 4.0 min / shut off / cool down
Inspected for oil leaks, none found.  No unusual sounds or noise concerns
Upon completion of heat cycle, changed oil to Conventional Valvoline VR1 20W50

Trailered bike two hours to Doc's Performance Tuning for Dyno break-in & tuning. Approximately 75 miles ran on dyno / shut engine down due to rattling noise. I trailered bike home.

At home I checked pushrods for looseness, they were not loose. Then I restarted engine, no rattling noise.  Rode bike up to operating temperature. Then changed oil to VR1 20W50 conventional. 

Being that I wanted to know what may have caused the rattling sound, I checked rocker support plates, rocker arms, valve springs and again checked pushrod for looseness, then took out lifters to inspect.  That's when I found the collapsed rear intake lifter. 

With the practical and common sense from above I will replace with the one new Feuling lifter and use the other three in the lifter holes they came out of. Then I will return to Doc's Tuning to complete tune. 

can't go wrong at Doc's

  It sounds like you took precautions before taking it to the dyno. 

Did you notice if the "collapsed" lifter was on the nose of the cam when you removed it?  Did you try something like putting it into oil and pumping it up mechanically or otherwise confirm the plunger was stuck (like by seeing an actual floppy loose top pushrod seat disc)?

Quote from: kd on March 15, 2025, 12:59:09 PM  It sounds like you took precautions before taking it to the dyno. 

Did you notice if the "collapsed" lifter was on the nose of the cam when you removed it?  Did you try something like putting it into oil and pumping it up mechanically or otherwise confirm the plunger was stuck (like by seeing an actual floppy loose top pushrod seat disc)?

Nope, I just took it out, looked at lifter and saw it was collapsed, and I measured the distance between retaining clip to lifter plunger which was approximately 0.070" collapsed.

Now I'm wondering what effect the collapsed lifter had on the valve opening or closing with the lifter approximately .070" collapsed.  Would valve have remained open or closed on that rear intake with the failed lifter during operation?  Lifter may have been not operating properly while on whole time on the dyno.

Were it my motor with such an extensive, and expensive, build, I'd look at replacing all 4 lifters.

If the lifter looked collapsed with the pushrod still in place it could be leakdown since the engine was shut off. The valve spring is forcing the plunger down against the internal lifter spring.  If it showed the cup was loose against the pushrod cup retainer clip after removing the pushrod or the lifter ass'ly was removed then the plunger / piston was stuck as you indicated.

Cam position with the valve train (including pushrods) intact can not be trusted as an indication of a stuck lifter if the cam is on the lobe lifting at that position.

Lifter out of engine.  0.070" down, possibly more.  Would not pump up with oil can.


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Looks grimy inside the lifter.

Quote from: Ohio HD on March 15, 2025, 02:59:33 PMLooks grimy inside the lifter.

Like a line of grease?

Quote from: Hilly13 on March 15, 2025, 05:22:37 PMLike a line of grease?

This is what I see. Could be shadows, but it appears like there's some dirt.

I agree with Ohio.  I would be concerned about what that is and where it came from. (Or if it's still there)  It definitely is stuck too.  Removed the internal spring should be activated.

I see what you are pointing at Ohio, I have read on here before that some folks strip new lifters before installation, at the time I thought it was overkill, I definitely clean out pushrod tubes because I have seen crud and swarf in those, next lifter set will get a clean out as well now.

The other three lifters do not look like the failed lifter.  What you are seeing is more like a hard tar substance.  Perhaps the lifter failed, then combined with excessive heat and subsequently low oil pressure cooked the oil. 

I'd like to take the failed lifter apart for further inspection.  However, I want to Feuling to see the collapsed condition.  If I disassemble the lifter, the plunger may return to normal position under the retaining clip.

What I thought looked like tar.  Only an opinion, I recently had Darkhorse install their Man O' War flywheel in my crankcase.  While Darkhorse had my crankcase, they bored the lifter bores to fit oversize Feuling 0.0015" Race lifters which they shipped back with the case.  The crankcase sealant is black.  Plausible explanation could be the tarry substance I see in the rear intake lifter is black case sealant.  I installed the lifters after I received the crankcase back from Darkhorse while completing the engine assembly.  As anal as I am about cleaning, I did not clean the lifter bores.  Possibly a micro amount passed through the lifter oiling hole.

And on the bottom of the pushrod there were three small black specs.  I had to use a scotch brite red pad to get it off.

What you are seeing is wear on the lifter bore most likely caused by the lifter itself failing. I'd guess from too tight a fit between the plunger & lifter body.

I appreciate your response, thank you.... I went to your website and see you offer a 0.0002" oversized lifters.  It looks like Feuling is my only choice now due to the 0.00015" bore.  In previous builds I always used your 2313SE. 

The Failed Feuling lifter side oil feed hole is clean.  No evidence of it being blocked or grime.

It's probably not visibly blocked because the conamination entered the lifter and played havok in there seizing the plunger. The deposit in the pics could have easily made it out past the more loose fitting pushrod cup. From your description of the black case sealer is a possibility.  If it did enter the lifter body, some may have made it out the top to the pushrod cup AND up the pushrod to the rocker to lube the shaft etc.. 

Until you confirm what that deposit is, I personally would be pulling the rocker shaft(s) and pushrod(s) and inspecting them and the head cavity for a similar substance. It all comes from the same gallery to the lifter feeds. Being careful not to let anything get away with well place white shop towels or the like will show deposits that leak out (if any).  Knowing there absolutely is a deposite in at least that one lifter, not following up would keep me awake at night. I would probably open up the other 3 lifters on a clean white paper towel for a similar inspection. IMO, At this point there is a risk of a reoccurance that could take out the engine all together.  I personally would need to know before reassembling it.

Did you do the lifter installation?  If so did they all fit with similar drag / clearance?  Did you offer to send all four lifters to Fueling for inspection?

Quote from: kd on March 17, 2025, 06:46:35 PMUntil you confirm what that deposit is, I personally would be pulling the rocker shaft(s) and pushrod(s) and inspecting them and the head cavity for a similar substance. It all comes from the same gallery to the lifter feeds. Being careful not to let anything get away with well place white shop towels or the like will show deposits that leak out (if any).  Knowing there absolutely is a deposit in at least that one lifter, not following up would keep me awake at night. I would probably open up the other 3 lifters on a clean white paper towel for a similar inspection. IMO, At this point there is a risk of a reoccurrence that could take out the engine all together.  I personally would need to know before reassembling it.

Did you do the lifter installation?  If so did they all fit with similar drag / clearance?  Did you offer to send all four lifters to Fueling for inspection?

Yes, I installed and adjusted the preload on the lifters.  I plan to (one at a time) to disassemble, inspect and clean the other three lifters.  And whereas I have the rocker arms and pushrods out I will be looking at them and cleaning them.  I am only returning the one bad lifter to Feuling at their request as they warranted the one failed lifter.

As WFO Larry mentioned "too tight a fit between the plunger & lifter body". May just be a factory machining failure.  It's amazing that some micro debris or grime could pass through the lifter hole and squeeze such a tight tolerance between the plunger and lifter bore causing it to seize.

QuoteYes, I installed and adjusted the preload on the lifters.  I plan to (one at a time) to disassemble, inspect and clean the other three lifters.  And whereas I have the rocker arms and pushrods out I will be looking at them and cleaning them.  I am only returning the one bad lifter to Feuling at their request as they warranted the one failed lifter.

As WFO Larry mentioned "too tight a fit between the plunger & lifter body". May just be a factory machining failure.  It's amazing that some micro debris or grime could pass through the lifter hole and squeeze such a tight tolerance between the plunger and lifter bore causing it to seize.

I had a Fueling lifter also do the same a few years ago.
Took all 4 back to them to check them out. One had enough contamination that it would stick sometimes. Their lifters are setup tight I was told, and to make sure I do the recommended oil changes!

My fault, still using the replacement lifters after 70K miles and just pulled them out last month to have a look, still looking good and put them back in. Gotta say, no charge and  Fueling is very good at customer service!

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