Anyone ever drilled out a rocker shaft bolt while still in the engine?

[Tippy]

Originally Posted by boyt911sc

Tony

This is exactly what I want to do but for the 5mm (regarding ratchet wrench with allen "knub").

Originally Posted by Walt Fricke

Tipppy

1) I'm glad you have dropped the notion of drilling/grinding etc. That's just plain ugly, and really only has a role when tearing down a motor and finding stripped Allens, or perhaps ones which have been tightened so much (and the shafts have perhaps broken) that the bolt end protrudes so far into the nut end that the wrench can get no purchase, but the nut is slipping.

2) Are these shafts properly aligned? One end roughly flush with the "short" part of the housing bore? If so, why not just tighten them (assuming you didn't get them tight in the first place)? Which way to install the bolts is a matter of convenience (as you have found out) for interim work. If you do a full teardown you can take off the chain boxes/oil cooler to get needed access.

If not tightened, just tighten, using the schemes you are contemplating, which are the logical ones.

Of course, if you don't have the proper alignment, which is why you started down this path, well then it makes sense to swap ends once you have things loose.

I always install with the bolt end toward the flywheel. It lets me use a torque wrench with various extensions, rather than torquing by feel. But that's on my engine stand.

For a field install (as after replacing a broken rocker), just do whatever is easiest for the end rockers - bolt ends facing inward. I don't think many of us have a 1/4" torque wrench with a head small enough to fit in there anyway, so we compromise at that point.

You're probably right, just torque the darn things and let them be.

It's just my perfectionist side saying I will have to use special tools in the future so pull it out and do it the right way.

[304065]

Originally Posted by Tippy

This is exactly what I want to do but for the 5mm (regarding ratchet wrench with allen "knub").



You're probably right, just torque the darn things and let them be.

It's just my perfectionist side saying I will have to use special tools in the future so pull it out and do it the right way.

Listen to your perfectionist side. You have enough to worry about when you hit the starter and throw the fuel to it. There's always something that comes up that you didn't anticipate, so you might as well make sure that everything you can possibly do correctly is done correctly.

Also, remember that Porsche recommended a service interval to torque the rocker shafts of 3,000 miles. Yes, three thousand, right there in my owners manual. After a few hundred miles you will want to pop the valve covers off and check everything anyway, how are you going to do that without using a torque wrench on the M5 bolt?

That's the reason to have the bolt heads toward the inside of the motor and flush with the "thin" side of the cam tower. You can see if they have walked and can easily turn the M5 bolt to reset torque if they have loosened up.

After wrestling with the right way to do this I finally asked around- you simply need a torque wrench and a modified M5 hex socket to work. All described here:

Question for the Pros or Semi-Pros: How do YOU torque rocker shafts?

It's just going to be part of the routine at every valve adjustment and oil change from now on. The 993 was the only motor to solve this problem with different rocker shaft mounts and hydraulic lifters. . . 30 years later!

[Tippy]

Originally Posted by 304065

Listen to your perfectionist side. You have enough to worry about when you hit the starter and throw the fuel to it. There's always something that comes up that you didn't anticipate, so you might as well make sure that everything you can possibly do correctly is done correctly.

Also, remember that Porsche recommended a service interval to torque the rocker shafts of 3,000 miles. Yes, three thousand, right there in my owners manual. After a few hundred miles you will want to pop the valve covers off and check everything anyway, how are you going to do that without using a torque wrench on the M5 bolt?

That's the reason to have the bolt heads toward the inside of the motor and flush with the "thin" side of the cam tower. You can see if they have walked and can easily turn the M5 bolt to reset torque if they have loosened up.

After wrestling with the right way to do this I finally asked around- you simply need a torque wrench and a modified M5 hex socket to work. All described here:

Question for the Pros or Semi-Pros: How do YOU torque rocker shafts?

It's just going to be part of the routine at every valve adjustment and oil change from now on. The 993 was the only motor to solve this problem with different rocker shaft mounts and hydraulic lifters. . . 30 years later!

I definitely want to do it right so I don't have another walk on me.