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Burnt valve, looking for options


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Hey guys! First post, and unfortunately it's not a good one. New to Subaru's, but not cars in general. I work as a tech for Lexus.

 

So my mother has an '05 Lgt, just over 118k. A few months ago it threw a p0301 code, and started to idle a little funny at cold start. I figured it was a coil and would get to it soon enough. Cleared the code, and it stayed away for a few months. About 2 months ago, the code came back. In this time, the idle had gotten significantly worse. Still totally drivable, but it felt like the motor mount were going back or something. Just a constant slight rumble. Cleared the code again, and bought some coils. About 2 weeks ago, the car started REALLy bucking at idle. True misfire. Felt like a machine gun. So I bumped up the priorities and finally threw the coils and plugs in. No difference. Bummer. Checked spark, good. Checked fuel, good. Check compression, BAD. Cylinder 1 had 40psi, compared the to other 3 that were around 200+. Went further and did a leak-down test, and air was just pissing out the exhaust. After about 5 minutes of deliberation, it was decided the motor had to come out.

 

Pulled the motor friday night, and found a burnt exhaust valve in cylinder 1, just as indicated by my tests.

 

So now my question is, where do I go from here? I need some opinions/advice/critique since I'm so new to these motors. My plan is to buy 8 new exhaust valves, and have the machine shop install them, and grind or lap the seats. Also clean and inspect all the intake valves/seats.

 

- I'm assuming the lash needs to be reset with the new valves installed? The little buckets look like a total pain in the ass to set up.

 

- Are there any aftermarket exhaust valves that are stronger? Or should I buy the OEM sodium filled ones again?

 

- I've heard horror stories about the 2.5 head gaskets, was this straightened out by 2005? I'm planning on using the OEM 10105AA720 gasket kit, and want to make sure everything is kosher.

 

- The turbo looks to be in great condition. No noise or abnormal play/wear inside. I've heard the VF40's can be rebuilt as long as there's no wear or play in the shafts. Should I look into a rebuild kit or leave well enough alone? At 120k I'd HATE to get it all back together just to blow another $500 on a turbo next month.

 

I also sent the injectors out to witchhuntperformance to be cleaned and tested.

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Here are some pictures from the night for shits and grins.

 

http://i58.photobucket.com/albums/g247/danman2k06/0-1_zps1ab511f3.jpeg

 

http://i58.photobucket.com/albums/g247/danman2k06/image_zps2b6c772b.jpg

 

http://i58.photobucket.com/albums/g247/danman2k06/0-2_zpsc1052dec.jpeg

 

http://i58.photobucket.com/albums/g247/danman2k06/0-3_zps548bec73.jpeg

 

http://i58.photobucket.com/albums/g247/danman2k06/0-4_zps025e6801.jpeg

 

http://i58.photobucket.com/albums/g247/danman2k06/0-5_zpscb323326.jpeg

 

Here's the valve.

http://i58.photobucket.com/albums/g247/danman2k06/0-6_zps9b70b502.jpeg

http://i58.photobucket.com/albums/g247/danman2k06/0-7_zpsb2379cd5.jpeg

 

And how the poor motor sits now :(

http://i58.photobucket.com/albums/g247/danman2k06/0-8_zps0aec018a.jpeg

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Injectors could be source of burnt valve.

 

If all other valves are ok, replace just the bad one and shim just that one. You'd be best off taking the head somewhere that does them alot. They will have a collection of buckets to choose from. They cost about $25 each and sometimes it takes 2 or 3 tries before you get the right set of buckets. Stock valves are just fine.

 

 

How did you get a 200+ psi compression result?

 

If you are mostly stock, use stock headgaskets. If you are going to rebuild the motor yourself, get headstuds instead of the stock bolts. All you need is a torque wrench to install them. (stock bolts cannot be re-used and are tightened by torque-angle instead of just torque.) If the car is stage 2 or higher, go with something like Cosworth gaskets and switch to headstuds for sure.

 

I'd hate to see a turbo with 120k go back on a motor like that. It's a tough call whether to re-use or not.

(Updated 8/22/17)

2005 Outback FMT

Running on Electrons

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200 psi - that would be great for a NA engine running high octane fuel, not so great for a turbo engine. (Unless it's a low compression diesel...)

 

But then - some compression tools has a pretty bad precision, so if a cheap tool was used I would just file the figures under bad scale tool.

453747.png
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It's not the valves that are the problem, it's the factory tune. It is well known that the OEM map has a flaw and can cause burnt valves.

 

http://legacygt.com/forums/showthread.php/dangerous-cylinder-trims-5th-gen-lgts-193842.html

 

 

 

That's from my Tuner, he found the flaw a few years back.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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FWIW, I'd let the machine shop rebuild the heads and pick them up completed. Oh that's right, I think the cam's have to come out to install the heads.

 

I just let my machine shop give me back a long block.

 

You can use the stock valves, just get the car tuned soon.

 

The stock HG's are fine, I did have my machine shop install ARP studs.

 

Most guy's will send the vf40 off to Brian at BNRturbos and get a 16g that he sells.

 

I just went with a vf52.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Hey guys, sorry haven't updated in a few days I've been super busy between work and trying to tackle this headache. I tore into her a little deeper. The short block look amazing. Crosshatches still on the cylinder walls, no glazing or scoring. The bearings were just as good, no significant signs of wear. I also cleaned off the domes of the pistons. They had a decent amount of carbon buildup, but nothing I would deem abnormal for a 120k mile engine.

 

I dropped the heads of the the machine shop today. After speaking with two subaru specialty shops near me (one of the being AndrewTech, don't know if they're known on here), it sounded like one valve (or two) valves were all I needed. The machine shop I took them to has been around for two generations, and has a VERY high reputation. I've had multiple flywheels done there, and a jeep block bored before. Trust is defintiely established. I told him to check out both heads, let me know the condition of all the valves. He said the burned one really wasn't bad at all. He said he could grind the partner exhaust valve of cylinder one fine, but recommended replacedment just in case it had been overheated or mushroomed or weakened etc, from the first valve getting roasted. He would also set the lash of all the valves with the heads off the block. I questioned this, after reading a few people saying it MUST be done on the block. He said it's not a big deal, and they've been doing it for decades without issue.

 

So a few misc. questions I have now are:

 

- Is there anything else I should be replacing while the motor is apart? Oil pump, any internal seals that won't come with the gasket kit, etc.

 

- Should I replaced the trans (automatic) input shaft seal? The torque converter pulled out about 8 inches when I was removing the motor. I didn't realize it has this gnarly long shaft attached to it, and it was probably resting all it's weight on the seal. Not to mention getting pushed/pulled/jostled around during the motor lift.

 

- I'm hearing very conflicting reports on the head bolts. Some say replaced them, and get studs. Other say don't even bother unless you're going performance-minded. This is a bone stock rebuild.

 

- I'm still researching what to do about the turbo. I need this to be as reliable as possible, but also as cheap as possible. A replacement turbo looks to be out of the budget so I'm still pondering a rebuild.

 

Keep the brainstorming and critiquing coming guys, and thanks thus far!

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http://legacygt.com/forums/showthread.php/got-some-new-stuff-engine-r-r-184106.html

 

There's my thread. Lot's of good info there.

 

If you plan to keep the car, I recommend ARPstuds for the heads.

 

Oh Yea, nice to see you know how to work on the car.

 

Keep us updated.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Got a few more things cleaned off today. The pistons and tumbler valves were pretty dirty so I gave them a wash.

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps0d1c009e.jpg

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps0bf21ef8.jpg

 

Here's a closeup of the burnt valve. I didn't realize my pics were so small in the OP

 

http://i58.photobucket.com/albums/g247/danman2k06/image_zpse706fc61.jpg

 

I'm thinking I'm gonna go for the head studs. Better safe than sorry right.

 

- In regards to the turbo, I'm still up in the air on this one. I'm trying to keep everything bone stock. I emailed BNR about a rebuild, still waiting for a reply. I also ordered both OCV valves, as I've been reading their failure can blow a turbo too. Tomorrow I'll pull out the filtesr in the banjo bolts and inspect them as well.

 

- My gasket kit came in today. Holy hell there is a lot of stuff here. I'm gonna put a pic up of all the stuff that I don't know the location of. Can you guys tell me where some of these pieces go? Especially that funky foam.

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps5abdd767.jpg

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Updates! I figured I'd keep this thread going as a pictorial if nothing else.

 

Got the heads back from the machine shop today. MAN do they look good. They were cleaned, milled, guides checked, valve job with both cylinder 1 valves replaced, new seals, ports thoroughly cleaned, the whole shabang. Total bill out the door was $558 with $130 of that being valves.

 

Resealed the oil pan and the front oil pump cover. I've read that the philips head screws on the back pump cover can come loose and cause horrendous damage, so I took them all out, cleaned, applied loctite, and re-torqued.

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps225d4277.jpg

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps14299ef5.jpg

 

Here are the sparkling heads

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps09cb5760.jpg

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps364de721.jpg

 

New gasket and some fresh ARP studs.

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps3514880f.jpg

 

The culprit

http://i58.photobucket.com/albums/g247/danman2k06/photo_zpse686d15c.jpg

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps105e8460.jpg

 

And it's partner valves, which appeared to be not fully seating. On two opposing sides you can see where the valve was clearly contacting the seat from a wear pattern, on the adjascent sides there is no wear, and a black layer of carbon seems to have been starting to form.

http://i58.photobucket.com/albums/g247/danman2k06/photo_zpsaab8dedb.jpg

 

And how I left her for the night. Got one entire head on and torque down with the cams and all the fixins.

http://i58.photobucket.com/albums/g247/danman2k06/photo_zpscb9b39c9.jpg

 

Still waiting on the injectors, and another misc. batch of stuff from fred beans. Cam bolts, OCV valves, an exhaust cam pulley, and a new torque converter seal.

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Great pictures, I don't think anyone here has posted the burnt valve before.

 

Did you remove the filter from the front banjo bolt ? I did.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Forgot to mention, yes I did remove the filters from the banjo bolts. To my pleasant surprise, the were both spotlessly clean. Not a spec or particle inside them. So either the car has been well cared for as far as oil changes go, or they truly are worthless. In my mind, if enough sh!t is flowing through them to clog them to a point where you would have starvation - you've got bigger problems on your hands.
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Progress! I'm so happy this thing is almost done, and I'm sure my mom is too lol.

 

These little soldiers finally came back from Washington state. Total turnaround time was 16 days door to door. Witchhunter has an option where you can pay $25 extra to "expedite" their 5 day service period (usually knocks off 2 days). There was a note with the box when it came back saying "we didn't get these out as fast as we wanted to, no expedite charge was made". That put me at ease. They seemed to do an extremely thorough job, and it looks like I may have found the cause of the original lumpy idle...

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps22985479.jpg

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps33a624b6.jpg

 

I got the rest of the motor put buck together tonight. TGV's, turbo, intake, timing components, etc. But here's where I NEED YOU HELP! This is where experience comes into play. There are two hoses that I can't find a home for, and one dampener looking deal that is without it's proper hose. Anyone know the location of these?

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zpsd8969e06.jpg

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps2a274a22.jpg

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps3aa5f5cb.jpg

 

And here's where I left her for the night. So close to being back in it's home :)

 

http://i58.photobucket.com/albums/g247/danman2k06/photo_zps2e7e9d81.jpg

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1st hose goes to the turbo

 

2nd hose goes to blow off valve

 

can't recall the 3rd one.

 

 

oh yea ,ZIP TIE those hoses !!!!!!

 

I hope you tightened the fuel line clamps.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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