Lifter Question
#1
Lifter Question
Let me start by saying I'm not a gear head AT ALL. I've got an 08 fxdf with a 120r that started making some funky noise lately. The motor has less than 5,000 miles on it and since it's under warranty I took it to the dealer that installed the motor. As soon as I pulled up in front of the service dept. the tech that always works on my bike came out and said that he heard the sound when I pulled in. He said it sounded like a lifter and that a lifter probably wasn't "pumping up". I asked if this was common on the 120 motors and he said it wasn't. Needless to say I had to leave my beloved Bob at the dealer. Hopefully they can get it in right away and I'll get it back while the weather is still decent.
What the hell does a lifter not "pumping up" mean? Is this something major? Was there something I did to cause it?
Sorry for asking such basic questions but like I said I'm not a gear head and I could use some help.
thanks in advance for any help or advice any you technically savy folks can give.
What the hell does a lifter not "pumping up" mean? Is this something major? Was there something I did to cause it?
Sorry for asking such basic questions but like I said I'm not a gear head and I could use some help.
thanks in advance for any help or advice any you technically savy folks can give.
#2
The H-D OEM hydraulic lifter has .200" of "travel"; the range of vertical movement of the pushrod in the lifter body. The OEM non adjustable pushrods are designed to sit at the mid point of the travel, .100", leaving another .100" of travel. As the motor heats up, everything starts expanding and the valve train stack up dimension changes as the cylinders get longer. The lifter chamber is fed with oil from the engine oiling system and is under pressure, so when the cylinders elongate and introduce lash into the valve train, the lifter, "pumps up" to maintain zero lash, i.e., zero clearance between the rocker arm and the valves.
When a lifter fails to pump up, lash or clearance is introduced into the valve train and presents as noise; lash between the pushrod and rocker arm and/or lash between the rocker arm and valves.
Unfortunately,the OEM lifter quality has suffered lately due to the manufacture of the lifters now being in Mexico. The tried and true -B lifter has been replaced by the -C lifter and the quality is hit/miss. There are good aftemarket alternatives like VThunder, HQ Black Ops and Woods Directional but to maintain warranty you are probably stuck with a -C lifter replacement. Ask your tech if he can find you some of the "old" -B lifters.
When a lifter fails to pump up, lash or clearance is introduced into the valve train and presents as noise; lash between the pushrod and rocker arm and/or lash between the rocker arm and valves.
Unfortunately,the OEM lifter quality has suffered lately due to the manufacture of the lifters now being in Mexico. The tried and true -B lifter has been replaced by the -C lifter and the quality is hit/miss. There are good aftemarket alternatives like VThunder, HQ Black Ops and Woods Directional but to maintain warranty you are probably stuck with a -C lifter replacement. Ask your tech if he can find you some of the "old" -B lifters.
#3
The H-D OEM hydraulic lifter has .200" of "travel"; the range of vertical movement of the pushrod in the lifter body. The OEM non adjustable pushrods are designed to sit at the mid point of the travel, .100", leaving another .100" of travel. As the motor heats up, everything starts expanding and the valve train stack up dimension changes as the cylinders get longer. The lifter chamber is fed with oil from the engine oiling system and is under pressure, so when the cylinders elongate and introduce lash into the valve train, the lifter, "pumps up" to maintain zero lash, i.e., zero clearance between the rocker arm and the valves.
When a lifter fails to pump up, lash or clearance is introduced into the valve train and presents as noise; lash between the pushrod and rocker arm and/or lash between the rocker arm and valves.
Unfortunately,the OEM lifter quality has suffered lately due to the manufacture of the lifters now being in Mexico. The tried and true -B lifter has been replaced by the -C lifter and the quality is hit/miss. There are good aftemarket alternatives like VThunder, HQ Black Ops and Woods Directional but to maintain warranty you are probably stuck with a -C lifter replacement. Ask your tech if he can find you some of the "old" -B lifters.
When a lifter fails to pump up, lash or clearance is introduced into the valve train and presents as noise; lash between the pushrod and rocker arm and/or lash between the rocker arm and valves.
Unfortunately,the OEM lifter quality has suffered lately due to the manufacture of the lifters now being in Mexico. The tried and true -B lifter has been replaced by the -C lifter and the quality is hit/miss. There are good aftemarket alternatives like VThunder, HQ Black Ops and Woods Directional but to maintain warranty you are probably stuck with a -C lifter replacement. Ask your tech if he can find you some of the "old" -B lifters.
I appreciate it.
#4
One thing I left out that does not come up much in discussion about valve train noise is the fitment of the lifter in the bore. If the fitment is too loose, the lifter will have a hard time staying "pumped up" and tend to bleed down. The MoCo doesn't check fitment very close and so if you get a motor where the tolerances are min-max, like the lifter bore is the max and the lifter is the min and/or the pushrod is the min and the cylinder is the max, etc. you get one noisy motor. On the other hand, reverse those tolerances and you get a quiet motor.
#5
One thing I left out that does not come up much in discussion about valve train noise is the fitment of the lifter in the bore. If the fitment is too loose, the lifter will have a hard time staying "pumped up" and tend to bleed down. The MoCo doesn't check fitment very close and so if you get a motor where the tolerances are min-max, like the lifter bore is the max and the lifter is the min and/or the pushrod is the min and the cylinder is the max, etc. you get one noisy motor. On the other hand, reverse those tolerances and you get a quiet motor.
#6
Let the dealer replace the noisy lifter and your problem might go away. If not, see if the dealer will allow the replacement of the OEM lifters with an aftemarket part and still honor whatever warranty you have left. If the dealer will allow that, there are several aftermarket lifters that might work better.
#7
well, it wasn't a lifter after all. I found a pic on line because I didn't think to take one at the time.
The circled area is the bolt that sheared off. The noise was the head of the bolt bouncing around and banging against the cover. The tech was speechless. He said he'd never seen anything like it before.
The plan now is to try to get what is left of the bolt out. If they can't get it out then they'll start tearing it down.
Any ideas on how something like this happened?
The circled area is the bolt that sheared off. The noise was the head of the bolt bouncing around and banging against the cover. The tech was speechless. He said he'd never seen anything like it before.
The plan now is to try to get what is left of the bolt out. If they can't get it out then they'll start tearing it down.
Any ideas on how something like this happened?
Last edited by carseller0822; 09-20-2011 at 08:55 PM. Reason: added to the post
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#8
well, it wasn't a lifter after all. I found a pic on line because I didn't think to take one at the time.
The circled area is the bolt that sheared off. The noise was the head of the bolt bouncing around and banging against the cover. The tech was speechless. He said he'd never seen anything like it before.
The plan now is to try to get what is left of the bolt out. If they can't get it out then they'll start tearing it down.
Any ideas on how something like this happened?
The circled area is the bolt that sheared off. The noise was the head of the bolt bouncing around and banging against the cover. The tech was speechless. He said he'd never seen anything like it before.
The plan now is to try to get what is left of the bolt out. If they can't get it out then they'll start tearing it down.
Any ideas on how something like this happened?
No idea on how that happens unless the bolt was just defective.
Shouldn't be hard to get out; IIRC, that bolt is only torqued to 25 ft. lb. Worst case, new cams but I don't see a problem getting the rest of the bolt out.
Last edited by djl; 09-21-2011 at 09:27 AM.
#10
The H-D OEM hydraulic lifter has .200" of "travel"; the range of vertical movement of the pushrod in the lifter body. The OEM non adjustable pushrods are designed to sit at the mid point of the travel, .100", leaving another .100" of travel. As the motor heats up, everything starts expanding and the valve train stack up dimension changes as the cylinders get longer. The lifter chamber is fed with oil from the engine oiling system and is under pressure, so when the cylinders elongate and introduce lash into the valve train, the lifter, "pumps up" to maintain zero lash, i.e., zero clearance between the rocker arm and the valves.
When a lifter fails to pump up, lash or clearance is introduced into the valve train and presents as noise; lash between the pushrod and rocker arm and/or lash between the rocker arm and valves.
Unfortunately,the OEM lifter quality has suffered lately due to the manufacture of the lifters now being in Mexico. The tried and true -B lifter has been replaced by the -C lifter and the quality is hit/miss. There are good aftemarket alternatives like VThunder, HQ Black Ops and Woods Directional but to maintain warranty you are probably stuck with a -C lifter replacement. Ask your tech if he can find you some of the "old" -B lifters.
When a lifter fails to pump up, lash or clearance is introduced into the valve train and presents as noise; lash between the pushrod and rocker arm and/or lash between the rocker arm and valves.
Unfortunately,the OEM lifter quality has suffered lately due to the manufacture of the lifters now being in Mexico. The tried and true -B lifter has been replaced by the -C lifter and the quality is hit/miss. There are good aftemarket alternatives like VThunder, HQ Black Ops and Woods Directional but to maintain warranty you are probably stuck with a -C lifter replacement. Ask your tech if he can find you some of the "old" -B lifters.
Well said dj!!
Scott