Just another misfire/rough idle thread...

[xt2005bonbon]

ok. I am curious how the valves look like. Just so you know, when I scoped mine (#2), I freaked out when I saw a series of 'scratches'. I thought, that was it: ringland failure. but then, I realized it was from piston slap (top and bottom IIRC). And I was using a crappy borescope too (not HD, crappy color reproduction, poor focus).

[Infosecdad]

I'll try to get some decent pictures and post them here. I'm getting way too good at tearing down that side of my engine bay to get to the engine...

[Infosecdad]

:spin: exhaust valve clearance on #3 is perfect. :spin:

[xt2005bonbon]

ok. next....

[Infosecdad]

Yup. Got to put it back together. Then going back after the injector

[xt2005bonbon]

if the injector is fine, what will you do next?

[Infosecdad]

I'm running on the theory that the lower o-ring isn't sealing on the injector and is flooding the cylinder.

That would explain the horrid gas mileage, unburned fuel, backfiring, etc.

 

I picked the injector that had the best looking lower o-ring and installed it.

I also swapped the coil and plug between #1 & #3 just for fun.

If that doesn't do it, I'll get a new lower o-ring just to be sure, since all my injectors are older.

Once this is fixed, it's time for an oil change as well.

 

On a side note, I like the cooling of the Mishimoto radiator; but the extra width is a PAIN.

To pull the timing cover off to rotate the cams to the right place, I had to remove the fan.

To remove the fan, I had to pull the upper radiator hose.

A bunch of coolant drained later, I finally was able to pull the valve cover.

 

Kids had to go to bed, so I couldn't test it tonight (the blessing and curse of Stromung)

Will have to try it in the morning.

As frustrating as it was to find that the exhaust valve clearance was perfect, I'm really glad I don't have to replace buckets right now.

[rhino6303]

I'm running on the theory that the lower o-ring isn't sealing on the injector and is flooding the cylinder.

That would explain the horrid gas mileage, unburned fuel, backfiring, etc.

 

I picked the injector that had the best looking lower o-ring and installed it.

I also swapped the coil and plug between #1 & #3 just for fun.

If that doesn't do it, I'll get a new lower o-ring just to be sure, since all my injectors are older.

Once this is fixed, it's time for an oil change as well.

 

On a side note, I like the cooling of the Mishimoto radiator; but the extra width is a PAIN.

To pull the timing cover off to rotate the cams to the right place, I had to remove the fan.

To remove the fan, I had to pull the upper radiator hose.

A bunch of coolant drained later, I finally was able to pull the valve cover.

 

Kids had to go to bed, so I couldn't test it tonight (the blessing and curse of Stromung)

Will have to try it in the morning.

As frustrating as it was to find that the exhaust valve clearance was perfect, I'm really glad I don't have to replace buckets right now.

I would swap the injector with one from the other bank too if this doesn't work out. Do you use superlube grease on the o-rings when installing?

[StkmltS]

ok. I am curious how the valves look like. Just so you know, when I scoped mine (#2), I freaked out when I saw a series of 'scratches'. I thought, that was it: ringland failure. but then, I realized it was from piston slap (top and bottom IIRC). And I was using a crappy borescope too (not HD, crappy color reproduction, poor focus).

 

I also saw scratches inside my cylinder, but the piston was later confirmed to have zero cracks.

 

So don't freak out if you see minor scratches.

[xt2005bonbon]

Do you use superlube grease on the o-rings when installing?

 

 

+1000. I was not really doing that before. Once I did, I stopped having issue with injectors not seating properly.

[Infosecdad]

I've used either synthetic grease or motor oil to lube the o-rings on the injectors.

I've swapped so many injectors that I ran out of grease.

I'm fairly certain it was a lower o-ring on injectors that were causing the flooding.

I think because most of my injectors are older, so the lower o-rings have shrunk.

And on many of my injectors, it's enough to not seal well.

 

I tried burping the coolant this morning, and had no misfires for the 3 min running.

But I found that I didn't get the valve cover sealed correctly and dumped a quart of oil on the garage floor.

 

So...

When I get a break, I'll figure out what I need to do for the valve cover.

I also have new lower o-rings coming tomorrow if needed.

[xt2005bonbon]

I was also using motor oil but I guess it was not good enough. I got a set of orings from DW with superlube. Never had issues after that.

 

 

You probably did not let that RTV dry long enough?

[Infosecdad]

I may have screwed up more than just the RTV judging by how fast that oil poured out.

Guess I'm doing an oil change now as well :-D

 

I picked up some quick ultra grey, so hopefully that does it.

Gonna smoke/stink for a bit with all the oil on the exhaust.

 

I'm going to go to DW740s one day, I worry about pushing these stockers to 100% DC from time to time.

 

Really, really want to get this valve cover on and sealed because I'm dying to know if I finally figured it out.

[xt2005bonbon]

Even with being careful, and following the FSM the best I could, both of my cars have the driver side valve cover leak to some extent. It's not much, but I noticed it. At least, it does not stink up the cabin though. Yours will for a while!

[Infosecdad]

:spin: 0/2 on attempts to seal the passenger side valve cover...

 

I'm doing something wrong on the bottom edge, it's like there is not even a seal there.

I'm being very careful to slide it in and fit it.

Tighten in the FSM sequence... still no joy.

 

Gonna take a break, drink a cup of coffee, and try again...

[xt2005bonbon]

maybe oil is still slowly sipping in that corner after you placed the valve cover and messing up the seal. Yeah. It simply sucks. When I do mine, I also usually let them sit 24 hrs.

[Infosecdad]

Third try, half succeeded.

 

I’m using the fast ultra grey, sets in 5 min.

First time I spaced using any, hadn’t needed to on previous Subarus.

Second time, I went all the way around, but too thin.

Third time, did it to FSM spec, and am leaking out of an area that isn’t marked for RTV.

 

Guess I’m going to go all the way around on the fourth try....

It takes me about 60-90 min to get it all cleaned up for each try.

Edited March 15, 2019 by Infosecdad

[xt2005bonbon]

That sucks!

[Infosecdad]

Trying for the fourth time.

Praying that this does it, letting it sit overnight because it doesn't do any good to test any earlier than that.

If it doesn't work in the morning, then I have to call it for a week and get a rental.

I have too much going on next week to fight this.

[xt2005bonbon]

I'd say wait even a bit longer (like tomorrow night).

[lilredwagon]

FWIW, I always do valve covers with Ultra Black all the way around and let it cure for 24hrs. Haven't had a problem on any of them. Is it humid where you are? If so, you might want to let it sit for longer as XT2005bonbon suggested.

[Infosecdad]

I'm at a loss...

I can't figure how what's happening.

Was extra careful to double check everything clean, good bead of RTV all the way around.

Follow the FSM to the letter for bolt tightening sequence.

Let it sit overnight (even thought it's supposed to cure in 5 min).

 

...

 

Start it this morning, oil just start pouring out of the bottom side of the cover...

 

...

 

Sigh.

Well, gonna have to go get a rental car for the week.

Going to get another new gasket from the dealer in the chance that the first was is defective.

Get some Ultra Black

Try again at the end of the week.

I've never even come close to having an issue like this with valve covers before.

[rhino6303]

B25 or D25 heads?

 

If B25, are you leaking from the half moon seal?

[Infosecdad]

I have two half-moons, but they aren't the source of the leak (waterfall).

 

 

The two areas marked in red is/was where it was leaking.

 

The smaller area on the right/near the front is good now.

It only leaked when I tried spreading the RTV too thin.

 

The larger area, I can't seal for the life of me.

It's not coming from the half moons in the back, but just pouring out of the bottom edge there.

I have a suspicion that the "quick dry" RTV is actually drying too quickly.

 

I have some Ultra Black now (and a rental car).

At some point, I'll tear it down for a 5th time and clean it up.

I will try to see if I am going to try the same "new" valve cover gasket again or if I'm going back to the dealer for another one.

[lilredwagon]

Man that sucks! I hate doing the same job over and over again, I've had to re-seat my fuel pump maybe, 4 times to get the O-Ring to sit right, and it still looses vacuum if it sits for too long.

 

Those sections in red are pretty standard leak areas. I usually make the bead a little thicker on that bottom edge. Also, make sure there isn't any pooled oil in the head before you put the valve cover back on. I'm sure you covered that, but as it sits, the oil that was coating the surfaces slowly drips down and pools in that area. So if you pull the valve cover and clean both sides, and then get the valve cover all ready for re-installation, there is sometimes a pool of oil that collected in the 30 mins since you've cleaned it. At one point, I went the extra mile and cleaned the surfaces with brake cleaner and then alcohol to ensure a clean surface for the RTV. That one didn't leak either, but I don't think it was necessary to do the alcohol.

 

As long as we're being EXTRA cautious, you could also clean the valve cover mating surface super clean, and then put the valve cover back on as you would, but then jack the side of the car up to make absolutely sure that no oil drips onto that seal while it's drying. Totally overkill, but doing it a 6th time would just be a kick in the pants.