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Bottom end noise???

18545 Views 22 Replies 9 Participants Last post by  wguchone, 
schwaber77
I recently rebuilt the top end on my 01 Harley FLHTCUI and now I"m having some concerns about some noise that could be coming from the lower end of my motor.

I've got almost a 2000 miles on it since the rebuild and it was running great up until the last few hundred miles. She still runs great but it's developed a nasty ticking noise. It started off (after switching to full synthetic) quiet but has gotten louder with time and it's turned into more of a knocking noise. It sounds like it's coming from the front cylinder, down low on the left side and it's mostly noticeable while riding, under light load around 3000 rpm's which makes it even harder to diagnose. The ticking/knocking also kinda pulsates (quieter, louder, then quieter over the course of a couple of seconds at highway speed), kinda similar to the pulsating noise you hear when you have a wheel bearing going on a car which has me concerned that it's a bearing going in the bottom end (all other bearings (cam, inner primary, transmission) have been replaced). The noise does not exist when I pull the clutch and coast.

I'm in the process of going through the motor to try to narrow it down. I've pulled the primary to check the compensator and clutch bolts and both were tight per spec, refilled primary to the correct level and noise still present. I've pulled the cams and checked the bearings and all looks good there, reassembled and noise is still present. I've verified clear passages through my push rods and adjusted from .130" to .140" and the noise is still present. I've got the top end apart now to check the rockers and those were bolted down solid and checked side to side play in the rockers and those seemed within the acceptable ranges (0.005" to 0.015"). I did install the ROCKOUT rocker shaft inserts although I don't believe those will make a big difference since the shafts were solid and bolts had no indication that the shafts were moving. At this point, probably this evening I will be pulling the heads and jugs to check the valves, cylinder walls, pistons and to see if there's any up and down play in the piston to crank assembly. I've also done a variety of other checks like cranking on the exhaust mount bolts, tightening exhaust chrome covers, making sure there's no unwanted areas of contact but at this point, I'm pretty sure it's internal to the motor. I'm thinking, if I don't find anything there, I'll try new lifters but the ones that are in there are S&S and were new with the rebuild so I'm not too optimistic that'll have an impact. Beyond that, I'm kinda at a loss as to what else it could be. Maybe the compensator but that doesn't seem likely as generally that seems to have more of an effect on the sounds when starting and shutting off the motor. So, what else can I think other than something going in the bottom end...

The fact that, to me it sounds like a bearing and considering I've changed just about every bearing except for the ones in the lower end, I'm thinking that it must be coming from the lower end. I've been in contact with Darkhorse and he's quoted me for a lower end rebuild (truing and balancing the crank, changing out bearings, new connector rods...). I just don't want to go that route right now if I don't have to $$$ but I also worry that I'll get the bottom end rebuilt and it'll still make the noise when I re-assemble....

Any ideas guys, would be greatly appreciated!

Thank you,
Chris

01 Harley FLHTCUI 90,000 miles
converted to carb
CV40 carb 48/200 jets w/Sporty Needle adjustment screw 2.5-3 turns out
SE Breather with K&N High Flow Filter
Stock heads, reworked by BigBoyz
TC88 jugs bored out to 95" w/mcr
SE 95" Flat Top Pistons
Andrews 37g cams advanced +4
w/stock plate and oil pump (Beasely spring)
S&S Lifters and Adjustable Pushrods (0.140")
0.030" Gasket
DTT Ignition Module Single Fire, Initial @4/Advanced @ 6
9.8:1 - 190ccp
Heads cut 0.04"/80cc
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schwaber77
Alright, update

Pulled the heads and the jugs and drained oil.

Heads, just by looking at them, I think are good. They look a little dirty from carbon build up but the build up is pretty minimal, kinda what I'd expect for a couple thousand miles. Kind of a dusting, not a thick layer. Valve seals look to be still seated and springs are all intact.

Cylinders are smooth, smooth as glass to the touch. Although, both cylinders have some vertical lines on both the front (facing on the bike) of cylinder and facing the rear but they're light and only visual, cannot feel them with fingers or finger nails.

The piston has scratches on the skirt, in alignment of the marks of the cylinder. Again, pretty smooth but they weren't there before. Otherwise, piston, I believe looks good. Some carbon on top but a pretty minimal amount.

Pulling on the piston while connected to the rod, there is a fair amount of slop left to right on the pin but 0 left to right down on the crank and there is 0 up n down slop on the pin or down on the crank.

Drained the oil and although there was a little metal on the plug, there was not any, I didn't find a single metal fragment in the oil. Oil looked pretty good for having maybe 800 miles on it. Somewhat dark but still had a golden tint to it.

So at this point, I'm not sure what to think. It seems apparent that I have some piston slap but would that be the culprit to the noise I'm experiencing? I guess I'd think if it were, the noise would come n go with the temp variations (more noticeable when cold and almost non existent when warm) but ever since this noise started happening, it's always been there, regardless of temp around 3k rpm and it's only gotten louder since. I think the slap probably has always been there, just not audible and from the sounds of it this may considered normal but correct me if I'm wrong.

So now I'm stuck with do I take the crank case out and send it in to get reworked or do I slap'r back together and try running dino oil (since this all kinda started with the switch to Amsoil syn), try new lifters, maybe a new SE compensator....I don't really know what's left to try and if I did, would I just be wasting time and $ when it's likely something in the lower end giving out. Kinda frustrating, I should be out riding! ;)

Thoughts, suggestions. I appreciate it.
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schwaber77
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pics of observations...

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jammer45u
Piston ring groove clearance too large?
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rootintootin
Some times what people think of as piston slap, is actually the motor pinging, sometimes too much timing, sometimes heat related. If all else seems to be OK and nothing mechanical makes a difference, might play around with some of the ignition settings to see if you can get a change. Maybe remove some of the initial advance, use a lower curve, etc. Summer blend fuel might make a difference too.

Or the old "they all do that". Mine makes some noises that I don't particularly like, in the low to mid 2K range, but it's been like that for about 40K miles. It seemed to start after I did the top end too. It isn't always so noticeable, and doesn't seem to affect the motor any. Just saying you could be chasing a noise for a long time.
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autoworker
At the very least you're looking at new pistons and fresh liners. Based on the looks of the piston skirts it looks like a lot of contamination has been floating around.I would rotate the assy. with the rods and see if any roughness is felt.

At 90,000 mi. it wouldn't be unheard of that the rod journals and or pin are failing.
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Thermodyne
That motor looks like it was put together dirty.

I'd recommend that the whole thing be pulled down and flushed out. Then I think you'll find that it needs even more work.
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KingofCubes
We've seen a lot of these front rods go out. We would rebuild the crank assembly with new parts and go with 98" pistons. Be sure to include pulling the oil tank, flushing, and replacing all oil lines. Do you use an oil cooler?
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T
Has that motor ever had a failure of any kind in the cam chest? Sometimes debris from that gets in the crankcase..
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jammer45u
Wouldn't dirt and debris effect the entire bore? That cylinder looks clean on pin ends, scuffed along thrust sides.

Are pistons floating free and easy on wrist pins? Ring groove and gap clearance in spec?

Didn't happen to get it hot did ya? Dyno, extended time on lift with no air flow?
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schwaber77
"Piston ring groove clearance too large?"

I measured and remeasured when installing. I forget the gap #, I'd have to go back in my records to look it up but I'm pretty confident that all was good considering the time and care I put into'm.



"Some times what people think of as piston slap, is actually the motor pinging, sometimes too much timing, sometimes heat related. If all else seems to be OK and nothing mechanical makes a difference, might play around with some of the ignition settings to see if you can get a change. Maybe remove some of the initial advance, use a lower curve, etc. Summer blend fuel might make a difference too.

Or the old "they all do that". Mine makes some noises that I don't particularly like, in the low to mid 2K range, but it's been like that for about 40K miles. It seemed to start after I did the top end too. It isn't always so noticeable, and doesn't seem to affect the motor any. Just saying you could be chasing a noise for a long time."

I hear ya, I've heard this as well. I won't say that it absolutely was not pinging because I could be wrong, I have been many times before but this to me sounded different than pinging. More of a metallic sound and it had that bearing kind of reverb going on not to mention the metal particles found...

As far as "they all do that", this was not a tick or light tapping sound. Started that way but quickly got louder and louder to almost like a light hammer hammering with the rpm's. It sounded terrible, I've never heard that from any bike. Even if that did fall under the "they all do that" category, there's no way I could live with it nor could the guys riding next to me. Sounded like it could explode any minute.



"At the very least you're looking at new pistons and fresh liners. Based on the looks of the piston skirts it looks like a lot of contamination has been floating around.I would rotate the assy. with the rods and see if any roughness is felt.

At 90,000 mi. it wouldn't be unheard of that the rod journals and or pin are failing."

"That motor looks like it was put together dirty."

I'd recommend that the whole thing be pulled down and flushed out. Then I think you'll find that it needs even more work."

"Has that motor ever had a failure of any kind in the cam chest? Sometimes debris from that gets in the crankcase.."

I was very thorough about cleaning, all parts were washed before reassembly. The emphasis put on cleanliness was pretty strong with all that I've talked to about my recent rebuild. I'm not ruling it out but I think I put it together pretty clean.

The only cam related failure that's happened was found before switching over to geared cams was that one of cam gear chain tensioners had a chunk break off of the edge of the plastic pad. That piece was located in the bottom of the chest. Otherwise, no major failures.



"We've seen a lot of these front rods go out. We would rebuild the crank assembly with new parts and go with 98" pistons. Be sure to include pulling the oil tank, flushing, and replacing all oil lines. Do you use an oil cooler?"

From everyone that I've talked to, rods seem to be the culprit... Well, I've been shopping around at the local shops and the motor is coming out and getting gone through. Lower end will be rebuild with the 4.5" S&S flywheel and the cylinders will bored. So I'll end up with 107". Seems like I'll end up with a Fueling cam plate and oil pump as well. Should be able to stay with the Andrews 37's cams. Pretty much be a new motor when done.
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schwaber77
"Wouldn't dirt and debris effect the entire bore? That cylinder looks clean on pin ends, scuffed along thrust sides.

Are pistons floating free and easy on wrist pins? Ring groove and gap clearance in spec?

Didn't happen to get it hot did ya? Dyno, extended time on lift with no air flow?"

That's a good question, I would imagine that it would effect the entire bore but both cylinders showed only on the front and rear sides. Pistons were floating freely with no noticeable slop (up/down or front to back). Gap was in initially but I didn't measure before taking it apart. According to my temp gage, especially on the recent warm days in the 80's, the temp didn't exceed 250F and it hadn't been dyno'd yet. I was planning on doing that in the upcoming weeks.
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rootintootin
schwaber77 said:
... not to mention the metal particles found...
Click to expand...


I don't think you have much choice except to keep going until you find out where they come from. Have you looked inside the filter? I'd make sure that whoever does the work now planned lets me put eyes on what they find.

Was there an initial break-in oil change after the top end work, like 1/2 hr. or 100 or 500 miles, or was the 2K the first time you went exploring? Those could just be part of the new parts getting settled in. Most of that would show up real quick after first start up. Or maybe just coincidental to recent engine work, something else entirely on a 90K motor. I hope not, 90K isn't that far off for mine.
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H
schwaber77 said:
pics of observations...
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Those parts look like they have normal wear. I think you may have jumped the gun by tearing the engine down without checking a few things first.
I would have verified the oil pressure when the tap/knock was at its loudest. Then I would have tried new lifters if pressure was good.
Piston slap is very noisy on a cold engine. It would have sounded like a diesel when cold if it was that loud when hot. I hope you find the problem but on a well worn motor, sometimes it's just cheaper to go for the long block rebuild.
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schwaber77
rootintootin said:
I don't think you have much choice except to keep going until you find out where they come from. Have you looked inside the filter? I'd make sure that whoever does the work now planned lets me put eyes on what they find.

Was there an initial break-in oil change after the top end work, like 1/2 hr. or 100 or 500 miles, or was the 2K the first time you went exploring? Those could just be part of the new parts getting settled in. Most of that would show up real quick after first start up. Or maybe just coincidental to recent engine work, something else entirely on a 90K motor. I hope not, 90K isn't that far off for mine.
Click to expand...
I have not looked in the filter but I've got it sitting out at home, just have to come up with a good way to open'r up without creating more metal debris.

This was not the initial oil change, it's had a few-at 50 miles, 500 miles, and again just beyond 1000 miles which is when I switched over to full synthetic. The noise started shortly thereafter, from ticking to bad knocking which is when I tore it down. Initial parts settling I'd imagine would've been done at the 50 and 500 mile mark. Very little debris was found then. I did find a fair amount at the 1000 mile mark and some of it was the larger pieces, found on the plug and the bottom of the oil drain pan... I was concerned at the time but the bike was running great and I just kinda figured that was the last of the initial break in fragments.
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schwaber77
hugie03flhr said:
Those parts look like they have normal wear. I think you may have jumped the gun by tearing the engine down without checking a few things first.
I would have verified the oil pressure when the tap/knock was at its loudest. Then I would have tried new lifters if pressure was good.
Piston slap is very noisy on a cold engine. It would have sounded like a diesel when cold if it was that loud when hot. I hope you find the problem but on a well worn motor, sometimes it's just cheaper to go for the long block rebuild.
Click to expand...
Don't tell me that...just kidding. I have been worried about the jumping the gun concern, I guess I still am considering what the current plan is will consist of dumping a few thousand into the bike.

My oil pressure has been good according to the gauge on my dash. I've been keeping a close eye on it since the beginning, before the noise started happening and even more so with the noise. It's always been at or above the mid point on the gauge (32 I think) while riding, higher when cold and the rpm's are up and no lower than around 20 when idling on the warmer days after a stretch of miles.

I thought about changing out the lifters but I've had a bad lifter before and this sounded much worse and different and was coming from low/left side on the motor and since these were brand new S&S at the time of the build, it seemed to me to be low risk. I guess trying that first certainly would've been easier and cheaper to try...

In regards to the piston slap, the sound or the tone didn't seem to change dependent on the temp. It was loud around 3k rpm, under light load regardless of if it was just started and cold or if it had been ridden for a while and at temp. Plus, it didn't do it at all during the first 1200 miles. The last < 500 miles and has gotten progressively worse just about every time I've fired it up and ridden it. I guess I imagined if it was slap, it would've been apparent from the get go, it would change based on temp and it wouldn't get worse over time.

The last couple of times I fired it up, I didn't just hear the knock either, it was also kind of a quiet, higher pitched howl too. Just sounds like a bearing with all the symptoms and my experience which I wouldn't argue, is limited compared to some.
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jammer45u
schwaber77 said:
I have not looked in the filter but I've got it sitting out at home, just have to come up with a good way to open'r up without creating more metal debris.

This was not the initial oil change, it's had a few-at 50 miles, 500 miles, and again just beyond 1000 miles which is when I switched over to full synthetic. The noise started shortly thereafter, from ticking to bad knocking which is when I tore it down. Initial parts settling I'd imagine would've been done at the 50 and 500 mile mark. Very little debris was found then. I did find a fair amount at the 1000 mile mark and some of it was the larger pieces, found on the plug and the bottom of the oil drain pan... I was concerned at the time but the bike was running great and I just kinda figured that was the last of the initial break in fragments.
Click to expand...
Just cut it open along the base with a hack saw. You won't leave any shavings you can't distinguish from engine debris when you unfold the paper.
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schwaber77
jammer45u said:
Just cut it open along the base with a hack saw. You won't leave any shavings you can't distinguish from engine debris when you unfold the paper.
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Thanks jammer, I'll cut it open this evening.
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jammer45u
hugie03flhr said:
Those parts look like they have normal wear. I think you may have jumped the gun by tearing the engine down without checking a few things first.
I would have verified the oil pressure when the tap/knock was at its loudest. Then I would have tried new lifters if pressure was good.
Piston slap is very noisy on a cold engine. It would have sounded like a diesel when cold if it was that loud when hot. I hope you find the problem but on a well worn motor, sometimes it's just cheaper to go for the long block rebuild.
Click to expand...
I disagree hugie. I'm not sure he has a huge issue, but I wouldn't want to see that kind of scuffing along the thrust line of that bore after only 2000 miles. Looks to me like it's been hot, short on lubrication or both.
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schwaber77
Alright, so an update and questions.

The motor has been disassembled and is out of the bike completely and pretty much ready for the shop to be rebuilt. Not much time to work on it tonight but I did get a few minutes to remove the pins/pistons from the rods and also to remove the stator cover. I wanted to remove the cover so I didn't have any resistance when trying to rotate the flywheel.

First observation was that there is what I'd consider a ton of side to side slop in the rod for the rear cylinder. I'm not sure off hand what the tolerances are but I'm guessing it's pretty minimal and it should be probably pretty tough to detect by hand but I could be wrong I guess. The front cylinder rod felt pretty solid. Am I right thinking that the slop is an issue and could be a factor in the knocking I was hearing? Maybe not even contributing to the knock but something that indicates that repair/replacement it needed?

Another observation, having removed the stator cover I was easily able to rotate the flywheel by pulling/pushing on the rod ends. When doing so, as the rear rod was coming up and to the peak of travel of the revolution, I could clearly hear and maybe even, lightly feel a chatter or maybe kind of an oil muffled ticking coming from within the case. This was observed during about a quarter of a full revolution, like I said, coming up and to the peak of the revolution. I've never been in the bottom end before so I'm not totally sure what to expect but is it safe for me to assume that I shouldn't be hearing anything and that it should be smooth as butter, especially considering there's still plenty of oil in the case and everything is definitely wet with oil?

All your thoughts and input has been and will be greatly appreciated. Have a good one.

Chris
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