[chukzelda]

Hi guys,

I went out to go for a morning ride on my 2008 bullet.  I went to kick start it and the bike tried to start but there was a mechanical clanging sound.  Tried again, no start, mechanical clanging sound.

I put the bike in top dead center and removed the tappet cover.  The rear tappet is fine, spins but does not go up and down, the front tappet is a whole different story.  It goes so far up and down that it doesn't feel like it's connected to anything at the top.

Ok, what am I looking at here guys?  I have a baaad feeling about this.

thanks
Chuk

[The Garbone]

Pull the tank and remove the front rocker cover. The rocker should be seated in the cup on the end of the push rod.  If the rocker is up and the pushrods is not putting pressure on it you probable dropped the seat on you exhaust valve.  Need to pull the head and have that valve reseated.  Happened to me on my 07 and they gave me a new head under warranty but that was years ago.   

[ace.cafe]

We routinely replace valve seats on Bullet heads, if it turns out that it is a dropped valve seat.
We have seats in stock, and we are all set up do to valve seats, because we do them on some of our head modifications.
You can mail  it in, and we can mail it back to you.

[chukzelda]

I'm going to pull the tank and rocker cover off tomorrow morning.  98-degs at the moment and the barn will be too hot to work in today.

Can someone describe what a "dropped valve seat" is and how it happens?

thanks
chuk

[The Garbone]

The seat is basically a harder metal (bronze I think) fitting/guide that goes around the valve stem.  It is machined into the aluminum of the head from the bottom (combustion chamber) direction. 

I have never done one myself but it requires heating the head to a few hundred degrees and inserting a cold seat.   They are held in place from friction once the temperature of the metal equals out.  When going down the road if you overheat the motor one thing that can happen is the valve seat will drop out and not allow the valve to close properly.

On mine it was dropped so far the piston was hitting the valve and I could not roll it with the kicker.  I rocked the motor and the seat popped back in, started the bike and road it 8 miles back to the house, it dropped again about a mile out and I finished the trip with it hammering and clunking.  In hindsight probably a really bad idea, 

Tension on the push rods is provided by the valve spring and if the seat hold the valve down the tension goes away.  Sometimes you can have a push rod just pop out of alignment and come out from under the rocker.   Usually happens at higher revs, but either way you have to get at the rocker.

[chukzelda]

ok, I couldn't wait to find out so I braved the heat and removed the gas tank and the front rocker cover.  In the picture below, you can see the pushrod sitting outside the cup of the rocker.  My question is,

1.  What tension keeps the pushrod in the rocker cup?  Right now it will just slip out.

2.  What caused it to slip out?

[chukzelda]

ok, looked at the valve itself.  In the attached photo, the red arrow is pointing to some sort of thin, circular piece of metal that has shattered from somewhere.  What the heck is it?

[tooseevee]

ok, I couldn't wait to find out so I braved the heat and removed the gas tank and the front rocker cover.  In the picture below, you can see the pushrod sitting outside the cup of the rocker.  My question is,

1.  What tension keeps the pushrod in the rocker cup?  Right now it will just slip out.

2.  What caused it to slip out?

!st question: The pushrods are adjustable in length. That's what you do when you "set the valves", you are setting the length of the pushrod. If they're adjusted to the correct length (it's by feel) they don't fall out.

2nd question: The pushrod "became short". This probably happened because the locknut on the adjuster was not tightened properly. The adjuster slowly turned itself in & the pushrod became shorter & dropped out of position on the rocker. The valve probably stopped operating even before it dropped out.

I ordered these a year ago:

http://nfieldgear.com/enfield-store/aftermarket-parts-accessories/performance/premium-avl-pushrod-adjusters.html

If I ever get 500 miles on my '08 Classic (it's a slow process for a multitude of reasons) I will change all my fluids again, install these little goodies & set the valves (I'm at 406 as of yesterday, running like a watch).

[tooseevee]

ok, looked at the valve itself.  In the attached photo, the red arrow is pointing to some sort of thin, circular piece of metal that has shattered from somewhere.  What the heck is it?

This looks like it verifies what The Garbone has previously said. I'm thinking I was wrong about the pushrod "shortening up".

[chukzelda]

Ok, learning alot today.  Took the cover off the rear rocker cover to compare.  I see the rear rocker has a silver piece of metal attached to it that pushed down on the valve.  The front one (per attached photo) is missing this piece of metal.  Hence, it won't keep any tension on the pushrod.

Ok, if that piece of metal is missing, where did it go?

[Arizoni]

I am not an expert on the old Bullets but the rocker arms look like they have (had) a hardened piece that pushes against the end of the valve stem.

This makes sense because the rocker arm is cast and it needs a piece of hardened steel to take the wear/abuse of pushing against the hardened end of the valve.  The hardened steel piece may have been brazed in place or it might use a mechanical interface to hold it to the rocker arm.
In either case it is not something that can easily be reattached.

If the exhaust (forward) rocker arms piece of hardened steel broke off that would explain why the rocker was able to rotate far enough for the push rod to disengage from the rocker arm as it has.

On a positive note, there seems to be nothing wrong with your valve, valve guide, valve spring or the valve seat in the cylinder head.
That means you don't have to worry about pulling the cylinder head or having any work done to it.

If you get a new rocker arm and replace it, your bike should be fixed.

As one rocker arm looks like it failed you would probably be wise to buy both the exhaust and intake rockers.  Where one failed the other one may also be thinking about failing.

OH.  My guess is the missing hardened piece probably fell down into the tunnel where the push rods are.

[cochi]

Chuk,  I have an 03 Bullet and that peice of metal doesn't belong there. You may have a broken valve collar. There are two of them one on top of the spring and one on the bottom. They are the hardened circular pieces that keep the spring aligned. The top one has the valve attached to it. I can't think of any other place this could have come from. Check the bottem collar and see if there is a chunk missing. Also, as Arizoni stated, there is a hardened piece of metal that the rocker arm rides on. It is a small round puck that is located in a recess on the top collar. It is directly over the valve stem. This protects the valve stem against mushrooming from the action of the rocker arm. In the old days, I think they were called lash caps. Good luck. cochi            

[Lwt Big Cheese]

Chuk deep breath, you're doing fine.   

Look at the Snidal manual and the exploded diagrams on Hitchcocks site to see how it all fits together.

The two retaining pieces are called "Collets" in the real rest of the world. May help in searching stuff. 

[Ice]

 The piece laying somewhat vertical and against the outer edge looks like a bit of rocker cover gasket to me.

Item no.15 is the valve spring retainer, no.16 is the valve spring retainer keepers or collets and no.18 is the lash cap



I hope this helps in some way

[chukzelda]

Hi again,

I really, really appreciate all the help you guys are giving me.  I know I'm learning a bit slow and am repeating some of the suggestions given, bear with me.

I agree that the piece of "metal" in the picture is actually part of the gasket.  It fits back in place perfectly.  I'm baffled where the "puck" at the end of the rocker arm went to.  I pulled the push rod out and looked in the side cover, no puck.  I carefully looked around the bike, around the rocker arm, nothing.

If I understand all this right, I need to order;

1.  A gasket set
2.  A rocker arm or assembly

I see nfield.com has the gaskets but I can't find a rocker.  Anyone know where I can order a rocker?

Chuk