[all4bspinnin]

Guys, some of you may remember my invidia EL header issues... warped flanges, multiple installs.... eventually we knocked the half moon into the valve cover a little bit causing a pretty nice little oil leak... well.. we fished the half moon out of the hole and put it back in with some black sealant... a hard drying plastic stuff... well... the car runs good, i check the oil every day and no oil loss...

however, when i pull up to a stop, after i start the car and have it running for a little while i get this horrible stink and i can see a faint bit of smoke comming from the hood/scoop... its bearly noticable but THE STINK (as me and nice-rice) have named it doesnt look like its going away...

im pretty sure im going to have to pull this invidia out for the 5th!!!!!! time and put a new half moon in... i cant take this header any more... im going back to a header that separates at the upipe..

long story short, how hard is it to change the halfmoon in between the head/valvecover while the motor is still in the car????

i figure, i can just pull the valve cover, wipe the area free of oil, input new halfmoons and seal with black silicone...

anyone have any advice? tips? etc? better header?

[all4bspinnin]

bump for info???

[chaos311clarity]

wtf is a half moon lol

[all4bspinnin]

its a little black cam seal like thingy
its located on the side of the cyclinder head in between the head and valve cover

[KarlSTI]

Originally Posted by all4bspinnin

its a little black cam seal like thingy
its located on the side of the cyclinder head in between the head and valve cover

The only thing I can think of is it is part of the valve cover gasket. On my motorcycle, you could see these....2 of them at basically the ends of the cams. Does this sound right? If it is, then the only good fix as far as I can tell would be to remove the valve cover and replace the gasket.

BTW, I've had motorcycles that would leak at these points and I'd use a little of that blue permatex during the install to keep it in place and that seemed to work.

OK, I hate to do this but....here's a motorcycle engine...see the 2 halfmoons between the valve cover and the head? That is actually part of the gasket there..the lower part.. Is this kind of what you're talking about but with the STi engine?


After a little searching I see that there are actual "half moon" gaskets out there too that are not part of the valve cover gasket....not sure though for the STi if this is the case. Either way, to replace them requires removing the cover as far as I can tell. That and using a touch of RTV blue....

[all4bspinnin]

Originally Posted by KarlSTI

After a little searching I see that there are actual "half moon" gaskets out there too that are not part of the valve cover gasket....not sure though for the STi if this is the case. Either way, to replace them requires removing the cover as far as I can tell. That and using a touch of RTV blue....

Karl, will that stuff withstand the heat of my upipe... its less than 3 inches away and it gets crazy hot right there

[Hitman83]

It's real easy to do. Just make sure you replace all the gaskets while you're in there. Oh and make sure the dealer orders the parts for the correct side of the motor (mine didn't AHH!!). Parts are about 60 bucks and labor should be no more than 2-3 hours.

[KarlSTI]

Originally Posted by all4bspinnin

Karl, will that stuff withstand the heat of my upipe... its less than 3 inches away and it gets crazy hot right there

Check with others that have done it but yeah there is a temp rating on the permatex products and I think ATV and take a lot of heat.

[HOLLYW00D]

anyone have a part number for these "half moon" seals?

[all4bspinnin]

Originally Posted by HOLLYW00D

anyone have a part number for these "half moon" seals?

oh man.... i forgot the part number...

a while back, i had the invidia EL header back one into the valve cover...

i had to pull the valve cover on the car... the half moon was like 2$ and the fuji bond was like 25...

as a matter of fact... i have a half moon out in the garage if anyone needs it...

-dave

[all4bspinnin]

oh and btw... i re used the gaskets inside the valve cover... they worked fine... just make sure you lay them in carefully and use the fujibond sealant.

basically... here's a quick writeup on doing the driver side valve cover halfmoons

1: pull header/upipe assembly off the car
2: take off coil packs
3: pull 2 black hoses at the top of the valve cover
4: take out the six 10mm bolts holding on the valve cover
5: CAREFULLY, loosen valve cover and "pop it off"
6: wipe bottom of head free of puddled existing oil... only go about an inch inward
7: Begin valve cover disassembly
8: Take out old halfmoons
9: carefully take out existing gaskets
10: spray thoroughly with carb cleaner, brake cleaner, etc... make sure it shines
11: dry valve cover... let it air dry or high pressure blower from compressor
12: lay gaskets back into valve cover (new is always better, used is a risk!)
13: Put sealant in half moon holes and put new half moons in, put sealant on top too
14: run fujibond along the gaskets in center and on big outer gasket
15: Begin reassembly
16: CAREFULLY line up valve cover with head (2nd pair of hands is always good)
17: press valve cover tight and put six 10mm bolts back into head
18: check for tightness, be sure to check manual for torque #'s
19: input coil packs and tighten bolt
20: put 2 black hoses back on, may need new hose clamps
21: re-check everything on valvecover, you may see fujibond slightly sticking out
22: Put exhaust system back on car, do not crank!!
23: Let sealant dry for a few hours, I let mine dry overnight!
24: A few hours later, crank car and let idle and triple check for leaks
25: If everything is good, go on a slow cruise and work your way up in speed/boost
26: Slap your wrist and promise not to put yourself through it again!