rocker shaft mushroomed?

[bpu699]

Was putting my rockers back in. Most of the prior shafts went in fine, but 2 wouldn't go in. They measure .002 wider at the ends, then midshaft, clearly mushroom from prior torqueing.

At what torgue do these mushroom out and deform? I know "new torque" in Waynes book is 11-12 lbs. Rebuild torque as listed on this site is usually quoted at 18 lbs or the shaft will walk out.

At 18lbs, does that permanently deform the shaft? Or, did the prior owner go way above that torque reading???

And follow up silly question, I put in all the rockers BEFORE setting the timing... will this be an issue???

[dannobee]

I don't know what torque at which they'll distort, but I know that they're fragile enough that we'd see them crack right near the gap where the o-ring goes. Probably be easiest to just replace them.

You'll be fine with all of the rockers in. They'll actually help keep the cams from bouncing around from the spring pressure, as they do with only two rockers installed.

[faapgar]

Well the rocker shaft bolts can be used maybe 2 or 3 times.I always measure them for stretch.They lose their elasticity after being stretched or over torqued.Spec used to be 25 inch lbs torqued with a Hazet 5mm socket with short allen protruding.Usually a replaced item unless it was you who had replaced them before.Fred

[bpu699]

Originally Posted by dannobee

I don't know what torque at which they'll distort, but I know that they're fragile enough that we'd see them crack right near the gap where the o-ring goes. Probably be easiest to just replace them.

You'll be fine with all of the rockers in. They'll actually help keep the cams from bouncing around from the spring pressure, as they do with only two rockers installed.

My only thought late last night as I was rolling around in bed, was whether I will be able to get the crank in sync with the cams with the rockers in. IE If I need to turn the cam 360 degrees to align with TDC will I be able, as wont one of the valves hit a piston, even with the adjuster threaded all the way out?

Didn't have a chance to try, ran out of daylight and energy this weekend...

[Flat6pac]

Back the crank off of Z1 about 30 degrees
All pistons are down now. Rotate your cams to key way up
Bring crank back to Z1
The motor is on TDC cylinder 1
Bruce

[bpu699]

Originally Posted by Flat6pac

Back the crank off of Z1 about 30 degrees
All pistons are down now. Rotate your cams to key way up
Bring crank back to Z1
The motor is on TDC cylinder 1
Bruce

Thanks, that really helps. Really don't want to hear that some rockers need to come out...

Bo