Newbie rocker arm shaft questions

[RazorRacer]

1. Why can't the shaft be removed, without dropping the engine, if the shaft bolt doesn't come out toward one of the center gaps? This would only apply to cylinders #1, #3, #4 and #6.
2. What problem(s) occur if the bolt is over tightened?
3. Clarify why the thinner flange needs to be inserted one way or the other.
4. Clarify why you shouldn't tighten the 8mm nut, only the 5mm nut.
5. If the rocker arm shaft falls out while the engine is running and doesn't obstruct the cam or valves, what happens inside of the cylinder?
6. If the rocker arm is causing a tapping sound, what is happening to cause the sound?
7. How does the rocker arm shaft effect oil leakage? In other words, what common mistakes cause the oil to leak and how is the oil leaking past the shaft? Please describe the oil flow around the rocker arm shaft.

[Jubbie]

I'll give it a try. The best folks to talk to are on the rebuilding forum.

1. Why can't the shaft be removed, without dropping the engine, if the shaft bolt doesn't come out toward one of the center gaps? This would only apply to cylinders #1, #3, #4 and #6.

I would think that you could remove any shaft. Not sure if the oil cooler gets in the way since I put mine in before that was in.

2. What problem(s) occur if the bolt is over tightened?

I have heard it to be recommended to go to a higher torque. I would do a search on this one in the rebuilders forum

3. Clarify why the thinner flange needs to be inserted one way or the other.

Not sure on this one

4. Clarify why you shouldn't tighten the 8mm nut, only the 5mm nut.

The 8mm nut turns the whole shaft which could wallow out the cam tower

5. If the rocker arm shaft falls out while the engine is running and doesn't obstruct the cam or valves, what happens inside of the cylinder?

I would think at first that the valve would close and no dammage would be done in the cylinder. I would worry about the rocker bouncing around and damaging the cam or binding between the cam and valve and causing it to open at the wrong time.

6. If the rocker arm is causing a tapping sound, what is happening to cause the sound?

I figure that this is your valve clearance which makes the valve and rocker recontact every open/close cycle

7. How does the rocker arm shaft effect oil leakage? In other words, what common mistakes cause the oil to leak and how is the oil leaking past the shaft? Please describe the oil flow around the rocker arm shaft.

The way I understand it is the rocker shaft is expanded by the wedged bolt and nut on either side. This expansion seals the shaft in the hole. But the hole can get worn and larger that the shaft can expand. This will cause the shaft to walk out of the hole and leak in the process. I used the RSR seals on my rebuild and have been leak free so far.

[KobaltBlau]

Originally posted by RazorRacer
1. Why can't the shaft be removed, without dropping the engine, if the shaft bolt doesn't come out toward one of the center gaps? This would only apply to cylinders #1, #3, #4 and #6.
2. What problem(s) occur if the bolt is over tightened?
3. Clarify why the thinner flange needs to be inserted one way or the other.
4. Clarify why you shouldn't tighten the 8mm nut, only the 5mm nut.
5. If the rocker arm shaft falls out while the engine is running and doesn't obstruct the cam or valves, what happens inside of the cylinder?
6. If the rocker arm is causing a tapping sound, what is happening to cause the sound?
7. How does the rocker arm shaft effect oil leakage? In other words, what common mistakes cause the oil to leak and how is the oil leaking past the shaft? Please describe the oil flow around the rocker arm shaft.

won't answer all of them but:

1. I just removed #1, though my bolt exited toward the center gap.

2. damage to the aluminum cam tower; too much expansion force

4. because you just want to pull the wedges together, not turn the wedge in the shaft. look at all of the parts and you'll see what I mean.

5. the valve doesn't open, theoretically based on your conditions

6. probably incorrect valve clearance (valve needs adjustment)

7. either cam tower insert areas and shaft were not cleaned carefully, or cam tower is somehow damaged to allow leaks. I believe the argument against the RSR seals is that you can tell if a rocker shaft is loose because it leaks. RSR seals delay this, which could be a bad thing.

[RazorRacer]

Moved this post to the engine rebuild forum as suggested:

Newbie rocker arm shaft questions