Broken Camshaft

[WRIGHTPILOT]

Anyone every had a broken camshaft? My 2003 K1200LT just spun the pin on the intake camshaft gear. Thus resulting in a broken camshaft. The mechanic says the camshaft gear is a poor design. Is it possible that I may have bent valves as a result?

[dmatson]

Don't know if its a poor design but if someone has taken the cams out to adjust the valves and they don't line up the pin from the cam and the hole in the gear and they tighten it, it will bend the pin. I know of one who the dealer did this to his.

[dshealey]

If the camshaft moved out of time for over 1/4 revolution while the engine was running, then it is a very good chance that valves/pistons could have been damaged.

Don't know what the dealer was talking about though, as first, there are no gears in the valve drive system. Second, there have been quite a few million miles, probably billions on the K engine design, with very, very few failures to speak of. I think the valve train on these is a darn good design!

In over 5 years on this site, yours is the first I have ever heard of that broke! We have had a couple that wore cam lobes, but no breakage that I know of.

Also, I have seen a couple where re-installation of the cam sprockets after a valve adjust was done poorly and the pin damaged by shearing one side. Has your bike had the valves adjusted before? By that dealer? If so, he is likely covering up poor work done previously.

[grifscoots]

I think we're going to start seeing more of this. It happened to Monty's bike because a nut backed off of one of the cam caps and hung in between the sprocket and chain.

The caps are torqued to 9nM. Very little effort is used to do this. I saw several of my nuts had backed out when we tore my old LT engine down. That's one Hank (Rhinewest) had done head work to and Hank is one of the best mechanics I know. He now uses a small spot of blue loctite when re-installing cams.

I highly recommend everyone to check their torque on the cam caps whenever they have the valve cover off.... after adding a drop of blue loctite (which doesn't taste anywhere near as good as the red).

[McAllister]

just spun the pin on the intake camshaft gear.

The problem sounds like it was the loose bolt holding the sprocket to the camshaft. The pin only aligns the sprocket to a specific position on the camshaft. The load is carried by the bolt-up of the sprocket to the cam via the bolt. You could do away with the pin as long as you could correctly re-position the cam after pulling it out for a valve bucket change. (This assumes you have used cable ties to hold the chain in position to the sprocket.) I'd guess someone might have used the 19mm wrench on the cam to rotate it before they torqued the sprocket bolt. Or, bumped the rear tire trying to rotate the cam to check their new clearance. Either would load the pin in shear as Dave suggest.

Cap nuts are another issue. 9nm doesn't sound like much to torque them down but when I remove mine I get a good strong snap when they break loose. I clean both the nuts and the studs before putting them back together and use a torque wrench to do it correctly. Never have found one loose.

[WRIGHTPILOT]

I like the sound of loctite. Does anyone see a problem with adding a drop to the cam bolt? When I looked at the pieces of my cam and cam gear, I noticed the slot was severely elongated and the pin was sheered off flush. Also I'm assuming there is a shoulder on the cam that the cam gear slides over. The shoulder was in pieces. I'm assuming the bolt loosened up and caused the catastrophic failure. I want to ask the mechanic how loose the gear was. Thanks for your input. I'm really glad I found this site!

[tmgs]

I like the sound of loctite. Does anyone see a problem with adding a drop to the cam bolt?

No not at all, in fact I have used a drop of locktite on every cam sprocket bolt I have ever installed particularly on the HP engines

do not use red on aluminum that has to come apart often

[bushj1]

Anyone every had a broken camshaft? My 2003 K1200LT just spun the pin on the intake camshaft gear. Thus resulting in a broken camshaft. The mechanic says the camshaft gear is a poor design. Is it possible that I may have bent valves as a result?

the head is zero clearance and likely has bent the valves, 16 of them,ask monte.

[grifscoots]

Cap nuts are another issue. 9nm doesn't sound like much to torque them down but when I remove mine I get a good strong snap when they break loose. Inquiring mind minds want to know why you're remove them so much? I've only gotten the snap out of an untouched bike out of the factory. From there on out, no snap. How are you getting this snap everytime?


I clean both the nuts and the studs before putting them back together and use a torque wrench to do it correctly. Never have found one loose. How are you cleaning them? Brake cleaner and q-tips?

I've done 14 shim unders on different LT's over the years at tech sessions and for bud's. I'm pretty sure I know what I'm doing and what I've seen. Just take my advice with a grain of salt and check them if you've ever broke them loose.

[tmgs]

Just take my advice with a grain of salt and check them if you've ever broke them loose.

you know the "proper" way to check anything for torque is to break it loose then re torque it.

[grifscoots]

you know the "proper" way to check anything for torque is to break it loose then re torque it.But, first you have to know the definition of torque: tighten it down till it just strips and then back it off a 1/4 turn.

I don't know about you, Tom, but if I never have to torque another Harley head, it will be too soon.

[tmgs]

But, first you have to know the definition of torque: tighten it down till it just strips and then back it off a 1/4 turn.

I don't know about you, Tom, but if I never have to torque another Harley head, it will be too soon.


I actually miss working on the harley's

BWhahahahahahahahaha

[McAllister]

How are you cleaning them? Brake cleaner and q-tips?


No, I'm not as sophisticated as that. I bring home from work something that helps me clean the cam journal nuts. It's called a used tunafish can. You see, I take the nuts off the studs and put them in an empty tunafish can with a little solvent. A little swishing around to rinse off the oil and a couple of passes with the shop rag to dry them and they're ready to use again. And then I take the shop rag, dip it in the tunafish can and then wipe the studs to remove any oil from them. I figured this would work nicely and it does. The second rule of a good torque procedure is "the threads need to be clean and dry". How do you do it? Q-tips?

[grifscoots]

No, I'm not as sophisticated as that. I bring home from work something that helps me clean the cam journal nuts. It's called a used tunafish can. You see, I take the nuts off the studs and put them in an empty tunafish can with a little solvent. A little swishing around to rinse off the oil and a couple of passes with the shop rag to dry them and they're ready to use again. And then I take the shop rag, dip it in the tunafish can and then wipe the studs to remove any oil from them. I figured this would work nicely and it does. The second rule of a good torque procedure is "the threads need to be clean and dry". How do you do it? Q-tips?Thanks for the tip. I don't clean them, just a dab of the blue and on they go, but I like your way muy bueno. I do have a small, one gallon can of the commercial parts cleaner with the basket in it. Having them clean and oil free seems like it will take care of the backing off situation. Though, it will add a little time to the task (try it when you 5 or 6 bikes tore down in your gearage during a tech session with a bunch of guys wandering around jazzed on kkkkkkkaffee).

[Steve_R]

bunch of guys wandering around jazzed on kkkkkkkaffee).I prefer my kafffeeeee with GreenZone please. :D

[McAllister]

Though, it will add a little time to the task (try it when you 5 or 6 bikes tore down in your gearage during a tech session with a bunch of guys wandering around jazzed on kkkkkkkaffee).

Why would it add any time to your task? Don't know about you but in sessions I've done the idea is to get the participates to participate. They should be doing the work. You only show them how on the first one and then follow their progress, point out areas where they should be careful, help with questions, offer suggestions and keep the coffee pot full. There shouldn't be any of this "wandering around jazzed on kkkkkkkaffee" stuff. OK, time for another cup!

[ibbones]

Why would it add any time to your task? Don't know about you but in sessions I've done the idea is to get the participates to participate. They should be doing the work. You only show them how on the first one and then follow their progress, point out areas where they should be careful, help with questions, offer suggestions and keep the coffee pot full. There shouldn't be any of this "wandering around jazzed on kkkkkkkaffee" stuff. OK, time for another cup!You havn't seen Grif when a bike rolls into his garage. He meets you with a cordless drill and is taking off body parts (the bike's) before the kickstand is down. He is like a duck on a junebug when it comes to wrenching and when there are 5-6 bikes in his garage, he has a hand in them all.
The kkkkkkaffeeeee is for us so we can keep up with him.

[Steve_R]

The kkkkkkaffeeeee is for us so we can keep up with him.Never a truer statement, Bones!!!

[deputy5211]

No, I'm not as sophisticated as that. I bring home from work something that helps me clean the cam journal nuts. It's called a used tunafish can. You see, I take the nuts off the studs and put them in an empty tunafish can with a little solvent. A little swishing around to rinse off the oil and a couple of passes with the shop rag to dry them and they're ready to use again. And then I take the shop rag, dip it in the tunafish can and then wipe the studs to remove any oil from them. I figured this would work nicely and it does. The second rule of a good torque procedure is "the threads need to be clean and dry". How do you do it? Q-tips?

Only problem is the neighborhood cats follow you around all day looking for the tuna. :D