rocker shaft pinch bolt direction ?

[simsalabim]

Hello All,

While I may have found the reason for a persistent oil leak, I am not certain of the specific reason yet.

While I have not reviewed ALL of the numerous threads on the subject, it does seem that it is accepted that the shaft ends should be reasonably flush with the thin side of the carrier, and that upping the pinch-bolt torque to btw. 18-20 ft-lbs (on an older assembly) is recommended. Aside from that and the possible addition of the RSR seals, I have not heard much else aside from the possibility of out of tolerance carrier bores or shafts.

My question now is whether it is also important which side of the cam carrier (thin or thick) that the head of the pinch bolt (5mm side) should also be located ? I notice that all of the heads are on the thin side except for the number 6 (photo) which is opposite. This does make it easier to get my 1/4" torque wrench in on the head side, but is there any effect on the location of the shaft expansion zones or do the cones expand at the same relative places ?

Judging by the photo, it looks like there is some oil escaping from the nut side of the number 6 shaft and that could be my problem ?

I see no shaft walking on this bank of heads . All of the shaft ends are at the same place relative to the thin side as in the photo.

I would rather not pull out the rocker unless necessary. It would have to come out of the carrier side furthest from the oil cooler (clearance) which may contribute to some scuffing ?

I will try simply torquing the bolt head to the adjusted range first, I think. Trouble is, most 1/4" T-wrenches only go up to 200 in-lbs or 16.7 ft-lbs. I would hate to guesstimate the rest . Of course, the motor is in the car at this time.

Thanks for any advice/comments as always !

Bill

[Heinz911]

There is no difference but you cannot get the bolt in or out at the chainhousing or oilcooler side once the engine is fully built. Therefore the 1, 3, 4 and 6 bolts are facing the middle rocker. How you put in the middle 2 and 5 bolts doesn't make a difference. When you tighten them only turn the bolt side and hold the nut side steady.

[304065]

http://forums.pelicanparts.com/911-engine-rebuilding-forum/599340-question-pros-semi-pros-how-do-you-torque-rocker-shafts.html

[BURN-BROS]

I torque them to 170 inch pounds. If the rocker does not rotate without a back up wrench when you get to torque spec, them you are good.

[simsalabim]

Thanks very much for the feedback folks (and the helpful link as well). This removes that little nagging voice in the back of my head and is appreciated greatly.

I decided to back off the pinch bolt and slide the shaft a few mm's toward the mid engine side so as to perhaps find a smoother contact zone (can't hurt ?) and then retorqued to around 17 ft-lbs. I'll give this a try and see if I get lucky. Otherwise, I will remove all of the shafts and verify/replace/install the RSR seals during my next oil change. The valves were just adjusted and I'd rather not have to do it all over again in another 500 or so ...

Thanks again to this wonderful forum.

Bill

[gtc]

One suggestion that helped me: install the rockers and shafts dry, then drop some lube into the rocker lube holes after everything is tight.
Also, I read a lot of accounts of the shafts being difficult to install with the RSR seals, but I found that gently rotating the shaft while inserting it into the housing made the job go easily with zero torn seals.

[simsalabim]

Thanks GTC ...

While I believe I have seen some folks apply assembly lube to the entire shaft before adding the seals and installing, it makes some sense to me to install them dry (just like the valve covers, gaskets and cam carrier surfaces before tightening).

By the way, my 81 coupe and your 84 are the same color and also quite similar in set up ...

Thanks again, and keep on abiding !