rocker shaft seals

philippeF · 07-11-2005, 02:09 AM

Hi
cannot find the rocker shaft seal ref. for the rebuilt.
Is it a good upgrade or really not necessary ?.
thanks
Philippe

Fishcop · Fishcop's Garage

Phil, these are a really good "peace of mind" upgrade. For the $100 (Aussie dollars) upgrade - I definitely don't have any rocker shaft leaks.

They are a racecar part... I don't think you'll find them on PET, you'll need to specifically ask for them.

walt · walt's Garage

I got these from Pelican a few months back they were $1.60 US each. Part number C-099-103-52

hcoles · 07-11-2005, 06:53 AM

I got mine from EBS along with the major order for the top end parts. They seem like a good idea. Careful when putting them on not to accidently flip them and have the outside lip go in the groove. They seem to not present a problem when sliding in the shafts...just a bit of a push. I used Redline assembly lube. I heard of a good idea the other day....get a gun cleaning rod with barrel buffer type ends on a drill and clean up the bores in the cam towers. Of course you just want to buff'em and not really take out any material. Also if you get your rockers buffed check the dimensions in three places on each...sometimes the diameter is enlarged in the area near the groove on the outside...this will make them hard to slide in...or check all of them when you get'em back by sliding all the way through in the place where they will go..use asm. lube so you don't make any marks in the bores. Also...put together rockers and shafts and feel for play...I found 2 that my machinists didn't find that were loose. Remember to orient the bolts/nuts so that you can get the rocker out while the engine is in the car if you have to...this means you will not be able to use a torque wrench on all shaft bolts but do these last and you will have a feel for it. Also remember that the shaft doesn't fit evenly fore and aft in the cam tower bores..you want the grooves the same distance out from the inside the engine edge. You probably knew all of this.
-h

philippeF · 07-11-2005, 07:39 AM

thanks guys.

I almost knew all about your advices, but i still have learned something today.
Many thanks for your support,
Philippe
France

ChrisBennet · ChrisBennet's Garage

Rocker shafts should be installed dry/un-lubed. Only the miracle of friction is holding those puppies in the bores.
I squirt some oil in the rocker shaft oiling holes after installation.
-Chris

philippeF · 07-11-2005, 01:48 PM

you're right Chris, i had a doubt about that
thanks for sharing
Philippe

sammyg2 · 07-11-2005, 03:16 PM

I put them on my engine (from pelican) and have no leaks. I can't say if I would have had leaks without them or not but they are worth it just to be able to ask myself that question.

MotoSook · 07-11-2005, 03:26 PM

Chris,

Has anyone reported the shafts sliding out? I use a little lube to get them to slide in easier, and so I don't rip the RSR seals. Once the pinch bolts are torqued, it shouldn't matter whether the shafts were lubed or not during install, right? Any loading is perpendicular to the bore/shaft axis....

TimT · 07-11-2005, 03:45 PM

Iveseen rocker shafts that have started to walk.

I crank down on the rocker shaft bolts quite a bit more than the published torque specs.

MotoSook · 07-11-2005, 03:48 PM

Two elbow shakes while turning the bolt should be enough torque right

?

hcoles · 07-11-2005, 05:43 PM

Since I mentioned lube before install I would like to mention another thought re. that...

I assume that once the bolt is torqued the lubrication is not that much in play until something moves the shaft. The friction type can be catagorized as dry or an assparity type bond.

I'll agree with Souk.. better not to damage the seals or scratch bores or shafts. I also think that having lube around helps the cones force the shaft ends out instead of "binding". I did buff the cone surfaces to try and get ride of those ridges a bit...

For many of these types of situations you can ask people and get a wide varity of opinions. I'm not a professional mechanic.

ChrisBennet · ChrisBennet's Garage

Quote:

Originally posted by TimT
Iveseen rocker shafts that have started to walk.

I crank down on the rocker shaft bolts quite a bit more than the published torque specs.

Same here.
I can send anyone a broken cam carrier if you'd like to see what happens when a rocker shaft walks.

I don't remember if the factory manual states to put them in dry but I know Bruce Anderson states that they should be in his book.
-Chris

hcoles · 07-12-2005, 07:49 AM

At this point I'm trumped. I used asm. lube and torqued to spec. If the rocker shafts walk I will not be happy. This now makes a few places where I heard that people "over" torque to shafts...so there my be a latent issue there. I guess I will just pray at this point that the German engineers did their homework and tests and that my situation is not outside of the +/- 3 or 6 sigma.
-Henry

afterburn 549 · 07-12-2005, 09:26 PM

all I know is please use the seals..I had a few gost leaks,and as soon the seals were installed they were gone!!

tctnd · 07-12-2005, 09:40 PM

SOUK is correct; go ahead and lube them for assy. Even if assembled dry, oil will penetrate every space an oil molecule will fit and the final grip will be the same.
Phil

hcoles · 07-13-2005, 06:40 AM

Phil, thanks I feel a bit better...the thought of the shafts walking out is very scary....if the shafts are walking it is probably an indication that there is another issue like the rockers are binding on the shafts.

So far I've driven about 150 miles back and forth to Santa Cruz, I got the oil up to 250F with the ac on on Hwy 17. At this point no drips. Engine still running very nice.

-Henry
89 3.2

hcoles · 07-15-2005, 03:47 AM

Now that I think about this some more. The rocker shafts take a huge beating....probably something like 3 times the force that the cam puts on the rocker pad. An estimate...200lbs x 3 = 600lbs. Imagine pounding on the rocker shaft with 600lbs...say at 1000 times a minute or more. It's a wonder that the AL housing holds up at all. This is making me think there is something to the over torqueing assuming nothing splits. That's another 1 cent on the subject.
-h