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So, you swapped plugs in a 3.0? SORCERER!!!


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Today I did some work on the 03 H6 OBW. I need to change the plugs.

 

It's looks impossible. Yes, people 'claim' to have done it, Yes, I've read everything I could about it.

 

The distance in the back between the coil pack and the frame is less than the length of a sparkplug! And, if the thickness of the coilpack is gonna allow for a 'turn' into the sparkplug 'tube' then it looks like the coilpack can't possibly get out of its 'well'.

 

And, do I just shove the coilpacks out of the way? They have connectors on them, do I lift a tab or squeeze them somewhere to pull the connectors off? (I wouldn't mind doing this, I believe in 'wiping'/reconnecting connectors generally, then i'd coat them with dielectric grease to reduce contamination.)

 

How likely am I to slam the electrode shut on the sparkplug trying to get it started? Can I slip it into the tube already in the socket?

 

I have bought a wobble extension and a 5/8 sparkplug socket, with no rubber or magnet inside (I only had 13/16). I also have some universals and other tools.

 

I plan to attack from underneath. I may do the 2 front ones, then the driver's rearmost to get it outta the way. Does this seem like a good plan for a noob?

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can not say I have ever done the 3.0 H6 - but I have done a 302 in a Maverick - with about an inch of clearance between the engine and inner fender - just takes a little ingenuity to get the job done (and small hands do help).

 

Me personally, I always start with the hardest ones - get them out of the way, then the others seem easier. hehehe

 

Good Luck!

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I use a wobbly spark plug socket, a 1" extension, and a 1" "wobble" extension.

 

You definitely do put the plug in the socket, then feed the socket and extensions down the hole - then attach your ratchet.

 

You can also just jack up the side of the engine - may have to disconnect exhaust and pitching stopper.

 

Removing the valve covers will give you a lot more room also. If they need resealed anyway....

 

GD

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I had a similar problem with the plugs in my quad-cam EJ20. Those rear plugs exited straight into the frame rails. :banghead:

 

I ended up doing the tools piece by piece.. I had to slip the socket in, then the wobble extension, and then snap the ratchet on. As it came out, I had to disassemble the tools again and unscrew it the rest of the way by hand before I could get the plugs out.

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I'd definitely do the most difficult first if I had EVER done this before.

 

well, a simple look over should give you a clue as to which are going to be more difficult and which should be a little easier.

 

Start with the ones that look like they will be the hardest to get to.

 

I like GD's suggestion of jacking the motor a little for easier access.

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OK, RockAuto sent me (a year ago) NGK ilfr6b 6481 'Laser Iridium Premium' plugs. While I can find them on NGKs .pdf catalog, I can't confirm they are appropriate for my 03 H6 Outback doing a brief 'reverse' search.

 

The gap is .031" or so on all 6. When I use the part finder portion of NGK's website, I get a different (maybe newer?) part listed in Iridium, and it shows a gap for that part of .044"

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i do them a fair bitt i find it a bitt easyer to undoo the lower mounts studs and strut brace and lift the engine a inch makes it a bitt less tight the coils come out only in one place takes about a hour to change them all not as hard as a 2.5 twin cam or svx

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first plug is out - this job is not easy.

 

plfr6 w'ever stock plug that I got out is over .040 gap (1 mm wire gauge passes through easily)

 

the plugs i got from RockAuto (laser iridium Premium ILFR6B 6481) are about .030-.031" or so.

 

I find conflicting data online as to what the gap should be, but, since these are different plugs/slighly different technology, I guess I'll put them in as is. Everyone claims not to adjust NGK so, I'm trusting these will work.

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folks say it's much easier to do with the valve covers out of the way, so i ordered valve cover gaskets. sometime before 300k they're going to leak bad anyway and they're already wet on one of my H6's and leaking a little on the other, might as well replace them and make the plug job easier.

 

if the rears turn into a wrestling match might see how many valve cover bolts there are?

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...The distance in the back between the coil pack and the frame is less than the length of a sparkplug! ...

 

More Reasons to Love Old-School Subarus... ;)

 

...NGK ilfr6b 6481 'Laser Iridium Premium' plugs...

 

I'll Like to see Pics Please! ... including the Socket on the Sparkplug's opening, to get the whole Area's Idea...

 

Maybe there's another way to do that... Seems to be so Difficult that might be easy to damage the Head's thread if the Sparkplugs aren't not properly Screwed...

 

Could you use your Hands to put the New Sparkplugs in Place?

 

Did you Finished the Job Already?

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Since I own a 3.0, I will try and get some pics this coming weekend.

 

Plugs aren't hard, at least not as hard as replacing the valve cover gaskets. Just need to take your time with each one, don't try and rush yourself, you'll get more frustrated. I use a 5/8" spark plug socket, a 1 1/2" extension, a short 6pt 18mm socket, a deep 6pt 18mm socket and a 3" extension.

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Got beat by about 5:30 - have 2 left to go. The driver's rear plug (actually, the coil) is the most difficult. Anyone attempting this should go ahead and remove the windshield washer tank, then you can remove a metal cable shield - 2 10mm bolts. This allows the rear coilpacl to move around with less restriction.

 

Even though I managed to get the coilpack out of the way, install the plug, I could not get the pack back on. I used my floor jack, a piece of wood and put some upwards pressure on the dvr's side motor mount area of the engine. Just about 1 - 1 1/2 pump of the handle. This gave me just enough xtra clearance to rotate the coil around.

 

Surprisingly, the new plugs seem to go in with little concern about cross threading. I did use anti-seize on the threads. And you can easily feel when they have bottomed so, putting another 1/2 turn or so on the plugs is not too difficult. I also put a little dielectric grease on the lower body part of the plug think the tube on the coil pack might make a more contamination resistant seal.

 

Gonna get some iced tea and attack the remaining 2 DS plugs.

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I also changed the PCV valve. With the washer tank outta the way, it's right there on a boss on the DS valve cover. It points up so, after removing the hose, you can slip a 19mm socket on a coupla long extensions down between som cable/hoses to take it out. It was oily, but not sludge-ey or carboned up. Seemss to have a piston or slug that would move around, but it didn't rattle. I installed a beck-arnley one I bought about a year ago. It has a tapered pipe thread so, I wrapped the new one's threads with some teflon pipe tape and installed it.

 

I'm leaving the undercover off for a coupla weeks to make sure There's no issues that might cause me to need to get back to the plugs or anything.

 

Also, as I was working on the pluugs, I used a 10mm box end wrench to cinch-up every valve cover bolt I could find. several moved 1/8 turn, a couple more, and one on the driver's side I swear was only finger tight! Couldn't reac all of them but I may try some from the top now that I know they may be a little loose. Might extend the time I need to do those gaskets a little while.

 

I may take some pics of the tools I used but really, you just need a lot of options for extension length from the plug socket to the ratchet. I made do with what I had, I can see where a wobble socket might be a helpful option, and one of those ratchets with the 'speed spin disc' or a thumbwheel ratchet would have been great to have.

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  • 1 month later...

well, there HAVE been issues.

 

twice, the CEL has come on. The first time was some misfire codes and a 'small vacuum leak code' (can't recall the code.) This was with a strange driver, within about 20 miles of a fuel fill-up. The car has had a coupla instance of spurious CELs before so, I tightened the gas cap and cleared the codes. Weeks go by and it set the CEL again. Misfire codes. This time, i also checked the FF data and bank 2 is being driven lean by the ECU. STFT is -6 and LTFT is -12. I'd LOVE to be convinced this is an O2 sensor problem or ??? but I just can't believe it isn't related to the 'European' plugs (NOW I've learned what those little flags are next to parts at RockAuto! )

 

It's gonna cost me another 45 bucks and probably a day under the car, but I've ordered the correct plugs and intend to swap them in, not sure when.

******NGK Part # 6619 MoreInfo2.png {#LFR6AIX11} Iridium IX; 0.43 Gap

us.gif ca.gif .044 ******

 

It runs smooth, but it seems the mileage is poor. I don't drive it regularly so, can't be sure the last trip meter was reset. It DID seem to lack a little oomph once recently when I floored on the highway, otherwise, performance is good.

 

maybe bank 2 has poor combustion and the O2 sensors on that side are picking up hydrocarbons and the ECU is leaning it out????

 

I feel stupid, but, if someone can learn from my mistake, it's OK with me.

Edited by 1 Lucky Texan
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If you're going to dive back in, I do have a few pointers. The tangs that clip the harness plugs onto the coils will sometimes break due to heat, wrap a zip tie around the coil pack to hold it on. I have also found it easier to do plugs on the DOHC 2.5s by unbolting the engine mount nuts on the underside of the crossmember and lifting the engine a bit so you can rock the engine for a bit more wiggle room.

 

You say misfire codes but which cylinders?

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If you're going to dive back in, I do have a few pointers. The tangs that clip the harness plugs onto the coils will sometimes break due to heat, wrap a zip tie around the coil pack to hold it on. I have also found it easier to do plugs on the DOHC 2.5s by unbolting the engine mount nuts on the underside of the crossmember and lifting the engine a bit so you can rock the engine for a bit more wiggle room.

 

You say misfire codes but which cylinders?

 

that was kinda weird - it wasn't just bank 2 IIRC.

 

I briefly considered taking them out and gapping them differently but, really, I just don't want to perform another experiment. If I had a spare car or more time, or maybe was better equipped....but, for the effort and 44 bucks, I'll just put in the proper plugs. Then, if i still get weird codes, I'll have eliminated a big unknown and can proceed normally with diagnosis. The only other thing changed was the PCV valve. Just can't see anyway it could create a condition causing the ECU to make big swings in fuel trim.

 

no one to blame but myself - still, less money than what a mechanic or dealership would have charged.

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  • 10 months later...

THis morning, I spent about 3.5 - 4 hours and swapped in the 'correct' plugs.

 

NGK Part # 6619 LFR6AIX11

 

 

car started. no test drive yet as it's still on jacks - changing oil, coolant and t'stat tomorrow.

 

 

I'm considering a 60-40 water/coolant mix. Just don't know if i really want to hassle with doing it. Probably put in the soob 'conditioner' too.

 

how usually drains out of an H6?

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