Rocker shaft issues...

[lateapex911]

So, I need to get my left side heads off....
So....I'm pulling things apart.

Background, '73 911E, but has a rebuilt 2.7, built by a reputable shop in the NYC area. There was an engine fire and the left side c
yliders injested crap and need serving. Right side compression is 175 across the boar, IIRC. I have fantasy that I can just do the left side, as this engine has very (sad to say) low miles, maybe 5K.
I did a 2.4 rebuild ages ago, so it's taken some time to get up to speed ..LOL

So far no issues until now. I can't get the rocker shafts out on exhaust #3, and #1.
On #3, the tension bold and cone nut are out, but the shaft will only slide so far and it just won't go any further. Not sure what to do there...

On #1, I can't break free the 5mm bolt, or the 8mm nut. THere's little space behing the cam housing to get a 5mm hex socket, so I'm using a shortened allen key, but no love. On the nut end I've tried my 8mm allen key with a 8mm box end on it's shaft for stability, but the hole is shallow in the nut and it just won't budge without seeming like it's going to slip out.

I assumed I needed to get the rockers off before pulling the cam..but, I'm not so sure now. It apears that I can back the adjustment far enough off that I can clear the base of the lobes and I could turn the cam to clear things as it removes?


So, thoughts?
A- I was planning on reusing the rockers and hardware, they weren't leaking and play felt great.
B-I figured I'd add the RSR seals just in case.
C-If I can't pull the cam and get the housing on the nench where I can have better access, are there tricks?
D-If I CAN pull the cam, should I even bother removing the rocker shafts on those remaining ? Or just put back in place.
E- I think proper tq is 18 ft lbs...how to measure? No way my tr wrench will fit! Tricks?
Thanks!

[JJ 911SC]

Originally Posted by lateapex911

... it just won't budge without seeming like it's going to slip out...

I started to round off the hex so I put the air gun it, came out right away.

[lateapex911]

I lack such a tool that will fit in there! And maybe the courage to just let it rip!

[targa72e]

You can always drill out the bolt (had to do this recently when one stripped) to release. Not that hard as allen hole centers the drill bit.

john

[Optimusglen]

Originally Posted by targa72e

You can always drill out the bolt (had to do this recently when one stripped) to release. Not that hard as allen hole centers the drill bit.

john

Do this with a left handed drill bit for bonus points, I've had them come free just from the heat and vibration from drilling.

[lateapex911]

I'm hoping to just get the cam out and get the rockers out when I have them in a more accessible location. I will say they feel like they have a bunch more than 18 ft lbs on them!

I have a 1/4" torque wrench enroute.
And a couple cam tools.

[lateapex911]

So, a follow up:.....I had a bunch of huge work weeks pop up, preparing for CV19....

I just couldn't get tools onto the hardware in exhaust #1 cleanly and I worried that I'd strip the hardware, so, I got a proper mount and stand, and hoisted the thing up. Once there I pulled the cam partly, got the chain cover loosened and out of the way, allowing better access, and was able to put much higher force on the hardware and viola! Success with #E1. I noted that it had some rust and "use" on the threaded hardware screw and nut. So those will be replaced
I had gotten E3s hardware out but the rocker shaft was still VERY tight in it's bore. Again with more access, I was able to use a socket as a drift to knock it out. It showed some scratches so its getting replaced.

I really appreciate the offers of help and coaching!

The good news is that the pistons look fine, so damage has been limited to the valves, which are now out for servicing.

[Flat6pac]

Realize, it was assembled wrong, lack of experience or assembled by a trainee.
The 5mm hex goes to the inside with the 8mm out by sheet metals.
Bruce

[nene]

Please put RSR seals on the shafts when all goes back together.

I recently did this to all of my shafts and OH LAWRD, not even a week of OIL!!

[Spenny_b]

You can get a torque wrench in there to tighten - I bought a 1/4" drive set intended for bicycle maintenance (specifically used for tightening carbon fibre seat posts, handlebars, etc). It's a lovely thing, not that expensive but seems really nicely made. Most importantly it does fit in between the castings to tighten the hex screws.

This is the one I got - available here

[lateapex911]

Originally Posted by Flat6pac

Realize, it was assembled wrong, lack of experience or assembled by a trainee.
The 5mm hex goes to the inside with the 8mm out by sheet metals.
Bruce

Hmmm, the Exhaust rocker on cyl 1 definitely had the 5mm towards the chain housing.
So, if I follow, cylinder 3 should have the 8mm towards the front of the car, cylinder 1 should have the 8mm to the back of the car, but what about cylinder 2?

[lateapex911]

Originally Posted by nene

Please put RSR seals on the shafts when all goes back together.

I recently did this to all of my shafts and OH LAWRD, not even a week of OIL!!

I have a bunch sitting in my shopping cart, thanks for the suggestion.

Just what do they actually do though?

[lateapex911]

Originally Posted by Spenny_b

You can get a torque wrench in there to tighten - I bought a 1/4" drive set intended for bicycle maintenance (specifically used for tightening carbon fibre seat posts, handlebars, etc). It's a lovely thing, not that expensive but seems really nicely made. Most importantly it does fit in between the castings to tighten the hex screws.

This is the one I got - available here

Yup, I already bought one for the reassembly!

[robh0377]

You can use your torque wrench with adapter for your kit

[Flat6pac]

2 and 5 don’t matter being access either way. I prefer the 5 side easily seen.
Also realize that the shaft goes proud of the small, thinner boss
Torque specs don’t work well on rebuilds, torque isn’t tight enough to lock the shaft from moving.
Bruce

[Richey]

The correct torque is 15 ft/lbs , a revision of the factory's original 13 ft/ lbs spec ; not
18 ft/lbs .

[mikedsilva]

I'm not as experienced as others, but if you do torque to 18 ftlbs as some suggest, does that permanently enlarge the bore in the cam tower? And if that's the case, what happens next time you remove and reinstall the rocker?

[safe]

Remove the cam chain housing to access the 5mm bolt properly, impact maybe.

[bickyd]

Originally Posted by lateapex911

I have a bunch sitting in my shopping cart, thanks for the suggestion.

Just what do they actually do though?

they are a rubber o ring that goes on each side of the rocker on the shaft and guarantee a positive seal when tightened down. cheap and great insurance. wish i had done it when i did mine.

[nene]

Originally Posted by bickyd

they are a rubber o ring that goes on each side of the rocker on the shaft and guarantee a positive seal when tightened down. cheap and great insurance. wish i had done it when i did mine.

Never too late, especially if the engine weeps oil