RSR rocker shaft seals
 

I have gotten advice to use the RSR rocker shaft seals when assembling my 964 engine. I priced them at about $5.00 each. WOW 5 bucks for an o-ring. They must be made out of unobtainium from the fatherland. I guess I'll bite the bullet and spend the money if they add to leak free engine in the end. Any dissenters?

Yeah, it is called a Porsche tax... But if you search well, they can be found for $1.36 a pop as I did recently. I won`t post the link here, but PM me if you can`t find them.

Aurel

Search. Henry Schmidt has some feelings on the subject. ;)

LOL!

Competition Engineering Advice - Walt
 

I ran across this on the Competition Engineering WebSite -
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C.E.s' war on oil leaks

911 Tech tip

Rocker shafts

It is my opinion that rocker arm/shaft installation is responsible for more 911 rebuild oil leaks than anything else.

Step 1: "Dry installation"

When you install your rockers you naturally put engine assembly lube on the rocker arm and shaft for break in.........right? Wrong!

Install each rocker and shaft dry, then after torqueing the shaft, then oil the rocker through the oil holes and either side of the rocker. You can still put cam lube on the cam and rocker face.

Step 2: "The torque"

I'm a fanatic about torque specs. I follow the factory bible to the letter 99% of the time. But this is one of the exceptions. The factory manual says the rocker shaft torque should be 1.8 kpm. Multiply that x 7.23 and it converts to 13 ft lbs. This spec is fine if you have the luxury of new cam towers and new rocker shafts, but that is a very rare occurrence. Usually the cam towers have been used at least once or twice before. So........you torque your shaft to 1.8 kpm and less than a thousand miles later it looks like your new engine was built by a hack. On used rocker assemblies increase the torque to 2.5 > 2.8 kpm and the rockers won't come loose and the engine stays dry!

I have been using this installation method since 1980 and it's always worked.

-Walt
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Note the "always" above. No mention of seals, or o-rings. He recommends 18 ft lbs.

Henry.S. will probably tell you if everything is purrfect you will not need them ( I think that is his stance) . No mater what, it is not a purrfect world, these things are getting old, some have been apart so many times Velcro is used instead of bolts.
They are cheap insurance to stop oil leaks... from impurrfect cam boxes, impurrfect gravity , impurrfect oil, impurrfect people, ECT.
I had a couple of oil leaks...sprayed it dwn washed it checked so many times and I swore it was not the rocker shafts..so i the end I stuck the "O" rings in, and yup fixed most of it.!!

hehehe oooopppsssss! I just installed a bunch of rockers with seals and assy. lube. Guess I'm screwed again!

Concerning Walt's torque spec... I trust he knows what he is doing, just that during tear down I found this:

http://forums.pelicanparts.com/911-engine-rebuilding-forum/251104-broken-rocker-shaft-cause.html?highlight=rocker

Suspected over torque...

Just something to be aware of.

Best regards,

Michael

You had better have a very good fit if your not using the seals, I just torqued one out side the cam tower, loose was .7085 torqued was .7095 thats only .001 difference, then when your alum expands faster than the steel you have a leak..

even over torq. would not do that !!!

Used them on my rebuild, at 1.50 each I see it as cheap insurance. Torqued them to 18ft lbs as recommended by John Walker in another thread I came across.:cool:

If they were good enough for the RSR then they are ghood enough for me

Perfect. Thanks guys; 18 ftlbs, no lube and seals should cover all the bases.

Woohooo. Just ordered 72 pieces for the tree engines I am or going to rebuild. Thanks Aurel. Andy

Thanks to the suggestions by you guys the RSR seals fixed the leaks on an engine that had been apart and back together 4 times by 3 different mechanics, twice by me, and I'm the one that finally got it to stay dry. If everything was perfect, they wouldn't have leaked in the first place, but they did until they got the RSR treatment.

just be careful installing the rocker shafts with the RSR seals. It is very easy to shear off part of the RSR seal when sliding the shaft in. Luckily I purchased two extra seals as I sheard of two. They may have still been ok, but I am a perfectionist.

John, I use the dry shaft installation method. Seems to be impossible to get the seals in dry without shredding them a tad. When I tore down my 2.7, I'd say about 50% of the seals came out with at least a little damage from my prior installation (were wet upon removal so probably not damaged then). Any tips?

I've heard that if you cinch the rocker bolt, and can torque it without holding the cap, it's good to go. If you have to use a second allen to hold the cap from turning as you torque, you've got one foot on a banana peel and the other one in the twilight-zone. :eek:

I coated the seals with Dow Corning 111 silicone o-ring lube and had no trouble with damaging them but I also used Moly assembly lube on the the rockers, also drops of oil in the oil holes before putting the valve covers on. Just didn't feel comfortable with having the rockers dry. JMHO No leaks with 8000+ miles on the rebuild.