How do you seal your valve cover bolts

[kmacht]

I have an issue with the aerovee that has been nagging me for a while now. What is everybody using to seal the bolts that hold the valve covers on? The holes in my valve cover are tapered. I swear that the original valve covers came with a tapered o-ring / plug that went under the bolt but I asked Sonex a while back and was told that it is just a normal o-ring. My original ones were toast after pulling the bolts so many times during the first 40 hours and every time I use an o-ring now it either gets chewed up or broken since I am trying to force a round o-ring into a tapered hole. I can't be the only one with this issue. I have been using some RTV along with the o-ring up to this point to make a seal but it creates a bit of a mess every time I want to pull the cover to adjust valves. Am I the only one with the issue? Did the valve covers change over the years?

Keith
#554

[Rynoth]

Maybe the valve covers changed? In my Aerovee delivered late 2014 the recess for the bolts is flat (not tapered) and the O-rings (fitted between the bolt head and the outside of the valve cover) seem to be doing the trick to keep the oil in.

[mike.smith]

Keith:

My covers are like yours. I bought some oversized black plumbing washers at the local hardware store. The kind that are very stiff, and not nearly as soft and pliable as o-rings. They also have a tapered face on one side. I never found any that were the right diameter inside and out, so I used over sized and drilled out the center hole to be just smaller than the bolts. I just tightened them down into the valve cover and eventually the oversized part just wore away and fell off, leaving the right size filling the cover's holes. I have not had to replace one in a year and a half, and they never leak. I'll look around and see if I still have some. If I do I can send you some, or at least take a photo so you can see what they look like.

[gammaxy]

I'm interested in hearing more about Mike's solution.

My understanding is Sonex recommends the -203 o-ring size. Mine get torn up pretty quick. I bought 20 or so on Amazon and treat them as disposable, but I don't really like that some of the torn o-ring can end up inside the rocker cover. I found some thinner o-rings in a VW gasket set. I'm pretty sure they are supposed to be rocker stud seals. They seem to fit my valve cover bolts perfectly and compress just enough to form a seal, but not enough to become damaged. I've had them in and out several times with no damage.

I think they might be pretty close to -011 size, but might be as large as -109.
http://www.marcorubber.com/sizingchart.htm

[mike.smith]

Here is what I used for the valve cover bolts (plumbing washers). I think this size is smaller than what I ended up using. You can see one face if beveled, and the other is flat. I up-drilled the hole for the bolt diameter (actually just a tad smaller). The outside was too large, but after tightening and un-tightening a bunch of times the outside extra just wore away and fell off, leaving the right size.

https://flic.kr/p/C4MxwU

[sonex569]

What I found at AutoZone was Fell-Pro Gaskets (Fuel Injection O-Ring set) Pn-ES 70599. These fit the covers as good as the originals and do not leak.

Regards

Dick
569SX

[Klimek]

Keith,
Keith is correct. The fuel injector O-ring has worked well for me.
I used, at first, an injector o-ring from an Audi / VW water cooled engine CIS fuel system. I measured the proper ring
from the kit (the largest in the kit) then just bought nitrile O-rings from then on. They usually last 3-4 cover removals
and never leak. I did add a stainless washer under the bolt head then the O-ring. They conform to the taper very well.
Have two long cross countries under my belt. Fayetteville, Ar. to Houston, Tx. and Fayetteville to Miami Cty. ( just south of
KC, Ks) Not a leak...
Good Luck.
Frank
ONEX 090
54 hours +
4.8 gph

[rkurian]

I replaced my valve covers with the stock black metal stamped ones and have never had any leakage problem when using the cork gaskets.