[FrankD]

So I fired up my 02 thunderbird this past Saturday and took it out for a ride. I noticed a strange rattling (more like metal "clanking") noise at idle. From what I can tell it sounds like it's coming from the left side of the motor.. maybe near the water pump. While riding I dont notice the noise but it may still be there.
Here's the strange thing though. When I squeeze the front brake (not the clutch) the noise goes away?! I was thinking maybe I was inadvertently touching something else while grabbing the brake so I got off the bike and only tried squeezing the front brake while off the bike.. and it still does it? As soom as a put some pressure on the front brake lever the noise goes away, and when I let go, the sound is back?
This bike is fairly new to me but I dont recall ever hearing that sound before... and it doesnt sound at all normal. I dont want to continue riding as I fear I may do some damage.

I recently took the carbs off to clean them out but aside from that, havent had any work done.

Any ideas what this could be?
Thanks!

 

[ssevy]

I think you are going crazy
I can't imagine a loose part from the left side of the engine that could be affected by depressing the front brake lever. If something is vibrating sympathetically at a certain frequency, adding the brake might quiet it, but only if it was part of the caliper assembly. If the bike is stationary, applying the front brake would not change the geometry of the front end any, so that would rule out any of the fork or triple tree parts. I think you need someone else's ears to listen as you depress the brake, preferably using a mechanics stethoscope, which will allow them to isolate the exact area of the sound. A short piece of garden hose will do in a pinch, plugging the opposite ear and moving it slowly around the area where you think the sound originates.

 

[FrankD]

Yeah, I plan on having a buddy come over while I try listening to a few parts with the mechanics stethescope...
I just find it extremely strange that squeezing the front brake causes the sound to go away. Maybe some sort of vibration issue? I want to take a video of it just to prove that I'm not going nuts!

 

[Slinky]

From what I have read, this sounds a lot like the sheared alternator bolt syndrome. Increasing the electrical load (brake light) makes the noise diminish.

I'm not speaking from personal experience, just what I have read on this forum. It seems to be a common fault.

 

[tbh9088]

Certainly has all the symptoms of the infamous "alternator rattle." The noise you are describing typically presents itself at idle, and will disappear above 2000 rpm. An increased electrical load will also load up alternator drive often quieting the noise - which is why actuating the brake lever (and in turn illuminating the brake lights) causes the noise to subside. Confirm this by running the engine at idle to reproduce the noise and tap the rear brake, instead. If the rattle sound stops, remove the alternator and inspect the rotor shaft bolt.

It's an easy fix and rather inexpensive. Search for "alternator rattle" in the forum and you'll find lots more info.

 

[FrankD]

Certainly has all the symptoms of the infamous "alternator rattle." The noise you are describing typically presents itself at idle, and will disappear above 2000 rpm. An increased electrical load will also load up alternator drive often quieting the noise - which is why actuating the brake lever (and in turn illuminating the brake lights) causes the noise to subside. Confirm this by running the engine at idle to reproduce the noise and tap the rear brake, instead. If the rattle sound stops, remove the alternator and inspect the rotor shaft bolt.

It's an easy fix and rather inexpensive. Search for "alternator rattle" in the forum and you'll find lots more info.

Holy crap you guys are geniuses! It must be that! It is very clearly and noticeable associated with me pressing the brake lever even slightly and at first it sounded like the alternator but I figured it must be the water pump below the alternator.

Is it a bad idea to continue riding before fixing it or should I be sure to fix before I run the bike any more?

I really appreciate the help

 

[tbh9088]

I can only share my experience: When the alternator issue first became evident to me, I'm certain I caught it between fill-ups on a 3000 mile trip (I wear earplugs when I ride and am pretty attentive to non-normal noises). I rode the remaining four hundred miles home without an issue, re-torqued the bolt, and have been fine ever since.

That said, I'm hesitant to recommend that you continue riding a once you've identified the problem. In reality, you're probably OK for at least a few hundred miles, but if the bolt shears off, you could have a minor headache on your hands to make the alternator serviceable again. And, from what I've read, the sound of terminal failure for this problem is not something you can ignore!

I'd advise you to first just re-torque the rotor shaft bolt. Removal, tightening, and installation shouldn't take more than 30 minutes. The trickiest part is getting the alternator re-fitted without pinching the rubber o-ring. I keep a few on hand just in case I have to remove the alternator ($1.46 on BB).

One other point worth making: Another user wrote just last week of bunging up the inside of the lower left alternator torx bolt upon removal. It can be tricky getting the bit and extension seated properly back in the nook between the alternator/clutch line/coolant hose area. Another member suggested loosening that bolt first while the other two are still under tension.

 

[FrankD]

tbh, thanks for the tips. I did some research on the topic and found out about the o-ring issue as well as something about replacing washers etc..
BB is great for parts but it takes forever to get the stuff. Was going to try my local Triump(/Ducati/Aprilia/MVAgusta) dealer but I wouldnt be surprised if they charged me $20 for that same O-ring.

Is it a good idea to have extra o-rings, washers, and bolts on hand or do you think if I'm gentle I can get it back together without damaging anything? If you recommend I get the parts, then what parts do I need?
I'll remove the lower bolt first with an impact driver so hopefully I wont run into the same problems that others are having with stripping the bolt head.
Thanks again for all your help. You guys are awesome!

http://www.bikebandit.com/triumph-motorcycle-thunderbird-2002/o/m17594

 

[KD5QOQ]

Look up a seal supplier locally and you can find the Oring for pennies.
As far as the hardware the same thing holds true, but I would consider an allen head rather than Torx.
By the way I did most of my growin' up in Yahpank, are you anywhere near there?

 

[tbh9088]

Forego the parts order and just try tightening the bolt for now. That may be enough to keep you on the road for the next 5-10,000 miles. Next time you are near a Triumph dealer or place an order to BB, throw in a couple of o-rings, the washers, and the bolt (if your VIN is affected - '02 TBird should be alright without the bolt). All told, less than $5. And, if you eventually do need them, it's great to have them already on hand.

BB part nos:
O-ring: 5559106-001
Bellville washer: 5559051-001
Flat washer: 5559052-001
Bolt: 5576085-001

There is no Triumph dealer nearby, and I'm impatient when it comes to waiting for parts. So, I tend to stock a variety of bits and pieces as I run across them or think about it (i.e. o-rings, crush washers, shift lever rubber, et al). BTW, Kawasaki wanted $18 for that o-ring. So, less than $2 for an on-hand spare was worth it to me.

More about the o-ring:
It's quite a mortal feat to install the alternator without pinching the o-ring. As the o-ring ages, it swells a bit and can become slightly over-size. This is when a slight off-axis insertion may lead to pinching the o-ring. I'll admit to being a little careless when I damaged the o-ring alternator.

More about tightening the bolt:
Be careful not to over-torque the bolt. I've heard of people shearing off the head of the bolt. There is no published torque spec, so I used a 1/4" socket driver to limit the torque I could apply with my hulking strength. You can immobilize the rotor with either a table vise, or cleverly spanning a long screwdriver between opposite rotor vanes (which is what I did).

Hope this helps.

 

[FrankD]

Look up a seal supplier locally and you can find the Oring for pennies.
As far as the hardware the same thing holds true, but I would consider an allen head rather than Torx.
By the way I did most of my growin' up in Yahpank, are you anywhere near there?

Thanks for the tip. Yaphank is about 45minutes east of me. There's a skeet shooting range out there that I used to frequent... but I just dont have as much free time as I used to.

 

[MickMaguire]

One other point worth making: Another user wrote just last week of bunging up the inside of the lower left alternator torx bolt upon removal. It can be tricky getting the bit and extension seated properly back in the nook between the alternator/clutch line/coolant hose area. Another member suggested loosening that bolt first while the other two are still under tension.

Even then it can be a pain and shear off. Best to try in impact driver on them from the get-go. Be prepared that you may have to drill the heads off if they wont cooperate.

My advice is generally, when you have them out replace them with similar grade allen headed screws.

 

[patrol21]

Hi All,

I've been following this thread and have seen these in the past. I have no issues with my alternater but this seems pretty common. Rather nip something in the bud before it becomes an issue. I am assuming we are referring to the mounting bolts, but where are these positioned and any pics/diagrams anyone has on placement of these would be appreciated. I would rather snug these down periodically for general maintence, then go thru some of the nightmares I have read about....thanks!

 

[MickMaguire]

Hi All,

I've been following this thread and have seen these in the past. I have no issues with my alternater but this seems pretty common. Rather nip something in the bud before it becomes an issue. I am assuming we are referring to the mounting bolts, but where are these positioned and any pics/diagrams anyone has on placement of these would be appreciated. I would rather snug these down periodically for general maintence, then go thru some of the nightmares I have read about....thanks!

the bolt in question is the impeller bolt on the end of the alternator shaft - you have to remove the alternator to see it. the issue is that it either stretches or its belleville washer looses spring so the assembly loosens off. Snugging it down wont help any until it has failed - even then, as said above that would only be a very temporary fix.

 

[patrol21]

Hey Mic,

Thanks...sounds like I'll leave it be until it becomes an issue.....cheers

 

[tbh9088]

I digress

Disregard any advice I provided earlier on just tightening the bolt to solve the alternator rattle. I've emprically demonstrated that this is only temporary. . .

After about 2000 miles after tightening the alternator bolt, the rattle reappeared tonight on the way home. Having kept replacement washers and a bolt on hand just in case, I immediately removed the alternator. As soon as I started applying torque to the bolt head, it sheared clean off!

I just de-listed the spare alternator I had for sale on eBay. I'll swap rotors and be back on the road. Then, I'll bring the alternator into a machine shop and have them extract the bolt. Lesson learned on this one.

So, take my NEW advice, and replace the bolt and both washers if you've got the rattle.

UPDATE TO MY UPDATE:

GOOD NEWS: It took all of 10 minutes to get the rotor removed, installed on the ZRX alternator, and put back on the bike. There were a few metal shavings from the bolt, but I cleaned up the splines, and everything works great.

BAD NEWS: I've reinforced my obsession with collecting spare parts. Have a spare alternator and the hardware already on hand saved my two weeks of riding time. Good thing that alternator hadn't sold on eBay yet!

 

[lassobosso]

Hi, I think I have this issue with my 99 Legend. I have ordered new o-rings(a couple extra just in case) and the belleville washer. As there i about a week delivery time on the parts I have a couple of questions.

1. If I pull the alternator and tighten the bolt and then accidentally cut the o-ring (before the parts have arrived), will I be stranded with my bike or just an embarrassing oil leak?

2. How harmful is it to keep on driving as it is until I get the parts?

3. Are there any other parts I should order when I'm at it?

Thanks in advance,
Lars

 

[denny]

Just an embarrassing oil leak.....I always tell folks "It's just marking it's territory"

I would get a new bolt and there is another washer in there too.
Those parts are not very expensive.

bolt T3150125
Bellville washer 3550031-T0301
Hardened washer 3550032-t0301

 

[parrycm]

The alternator goes on a lot easier, and shouldn't damage the o-ring, if you smear a little STP or silicone spray on the o-ring.

 

[lassobosso]

Just an embarrassing oil leak.....I always tell folks "It's just marking it's territory"

I would get a new bolt and there is another washer in there too.
Those parts are not very expensive.

bolt T3150125
Bellville washer 3550031-T0301
Hardened washer 3550032-t0301

Thats good to know and I was happily surprised as the price at my local dealer matched the price on bikebandit for the o-ring and belleville washer. I haven't ordered the bolt and the hardened washer yet but guess they'll match the price here as well.

One other thing, I was searching for the parts number on bikebandit but they didnt match the numbers at my dealer(or the numbers above) so where is a good source for that? It would save a lot of time if I could supply my dealer with the correct numbers.

Thanks!