I'm doing my 'scheduled' 2-year maintenance on my loyale, and I was thinking about the cam cases (and how they started to leak again). Has anyone thought about (or tried) to replace the silicone in the cam case groove with a long strand of o-ring material? Maybe cutting a piece to length, and leaving a small gap at the top of the case, where oil isn't likely to leak?

 

I would think that you could have a much better seal with an o-ring there, than with silicone. However, before I go out and try it, I keep thinking that those Subaru engineers must have had a reason for not using an o-ring there.

 

Any ideas? Does anyone have a cam case lying around that they could measure for me? I need to know the width and depth of the groove in the cam case, and my car won't be at that point for a few more days. I could take the dimensions to work and ask a few mechanical engineers about o-ring sizing and material choices. Maybe even score a free o-ring or two from the mechanics.

 

***UPDATE***

I talked to the guys at work, and I have the materials to try a couple of things. On one side, I'm going to try using a gore-tex cord to seal the cam case. It's rated for 600F, same as Ultra Grey. On the other side, I'm going to use a combination of the gore-tex, and a coppery silicone gasket material (not ultra copper, but something else). For other gaskets, I'm going to use something called "the right stuff". Our mechanics shop swears by it. Hopefully I'll have everything together this weekend, and then in the car by next weekend. I'll let you all know how it works.

Has anyone thought about (or tried) to replace the silicone in the cam case groove with a long strand of o-ring material?

 

I have thought of this. I have the parts to do it. I have the cutter bits needed to adjust the groove slightly. I haven't had the time to do it yet... It is coming back near the top of the list, however.

 

O-ring stock is surprisingly cheap. MSCdirect.com is where I got mine.

Loctite makes an o-ring fabrication kit - we have one at work. Lets you make o-rings of any size.

 

http://equipment.loctite.com/productDetail.cfm?productID=40488&productLine=O%20ring%20fabrication&pl=32&categoryID=292&category=O%20ring%20Fabrication%20Kits&subcategoryId=534&subcategory=O%2Dring%20Fabrication%20Kits

 

You can probably just buy the cord stock size you need and the "glue" and solvent to adhere the ends together without buying the whole kit. But even the whole kit is not too expensive at $85

 

GD

Might be cheaper to just use Anaerobic sealant though. A lot of folks swear by it although I haven't had any trouble with Ultra Grey RTV once the groove is thoroughly clean and with proper bolt torque.

 

GD

Ultra Grey is what I've used in the past - it seems to work for about 2 years before I start to see drips again. I have a tube of anaerobic sealant in my shop. Maybe I'll try 1 side with ultra grey and 1 side with anaerobic to compare. Or, maybe o-ring 1 side, and use anaerobic on the other.

 

AAAARGHH! I know there has to be a way to do this to make these engines just a little more bulletproof.

AAAARGHH! I know there has to be a way to do this to make these engines just a little more bulletproof.

 

Yep - Subaru did it. It's called the EJ22. Fabulous engine to work on. Easiest timing belt job I've ever done. 140k original on mine and no leaks anywhere. Properly designed gaskets and mating surfaces are things of beauty. Whoever designed the EJ22 sure knew what they were doing. Just think of how massive that changeover was from the Loyale to the Legacy, and they got it PERFECT the first try. Whoever was in charge of the coversion to open-deck should take lessons

 

That said, I think your o-ring idea has merit. It's never a bad idea to try to improve on this stuff. For example - I coat all my cork gaskets (oil pan, and EA81 valve covers) in a layer of RTV and let them setup. Basically I'm making a rubberized gasket that is impervious to oil. The plain cork will absorb oil and engine heat will cook it into a hard, oily, flat mess.

 

GD

The mechies at work are thinking of a silicone/grafoil combo. I have a couple of them puzzling about it at least. I should have a workable solution to try in a few days. I'll keep updating the thread as I get more info.

see update at top

Yep - Subaru did it. It's called the EJ22. Fabulous engine to work on. Easiest timing belt job I've ever done. 140k original on mine and no leaks anywhere.

i totally dig the EJ22 as well, but i've seen plenty of low mileage EJ's with oil leaks. from what i've personally seen i haven't seen anything more than age (the EJ's being newer) probably being the main contributor to EJ's leaking less. i've seen plenty of leaking cam seals, cam o-rings, valve covers on EJ engines with well under 100k, even on late 90's EJ's.

 

Subaru calls for anaerobic sealant, give that a try and see if it works better. then again it might not be the type of sealant you're using but the bead consistency, rubbing off when installing, grooves not being clean...could it be another reason they leak?

Yep - Subaru did it. It's called the EJ22. Fabulous engine to work on. Easiest timing belt job I've ever done. 140k original on mine and no leaks anywhere.

i totally dig the EJ22 as well, but i've seen plenty of low mileage EJ's with oil leaks. from what i've personally seen i haven't seen anything more than age (the EJ's being newer) probably being the main contributor to EJ's leaking less. i've seen plenty of leaking cam seals, cam o-rings, valve covers on EJ engines with well under 100k, even on late 90's EJ's. i could take a picture of a 1997 that i own that fits the bill.

 

Subaru calls for anaerobic sealant, give that a try and see if it works better. then again it might not be the type of sealant you're using but the bead consistency, rubbing off when installing, grooves not being clean...could it be another reason they leak?

use the right stuff sealant, there is reason that its so expinsive, it works and works well.

I have used that Gore-Tex stuff in the past, mainly when a piece of equipment needed repair and we didn't have all of the seals/gaskets on hand. It's some good stuff, comes in various width/thicknesses. Some things repaired seen air pressure of 150 psi, others seen fluid temps over 260 * F, with no leakage.

 

Probally was a bit tricky following the seal area of the cam case. But if you got it on properly, it should seal up with good results.

I use Toyotabond whenever I am dealing with one of my fathers company vehicles or my own. If I am in a pinch and I dont have any Toyotabond handy, I belive its called loctite 5500. Thats what the Porsche dealers use. Toyotabond is good stuff.

i was thinking about the cam cases (and how they started to leak again). I'll let you all know how it works.

 

please update!!!!!

i'll update my experience with a couple...or 20 subaru's. the recommended anaerobic sealants work great, there's no mystery or magic solution here. the key is probably in doing the job well. cleaning the grooves completely which is completely annoying. get the case seated without rubbing off/compromising the sealant bead and mating surface. torque it down properly. and others have used RTV, the Right Stuff....etc, etc....i don't think there's a magic pill here, just do the job right.