My head and how I made a hole right through an exhaust valve

[ciper]

I was driving up a mountain at 90-100% throttle for about a half hour. When I finally took my exit the car was shaking badly. While everyone went snowboarding I troubleshot the issue. By unplugging spark plug wires one at a time I narrowed it down to the rear passenger cylinder. I removed the spark plug and clamped a vice grip around it and started the car. It had spark. I then unplugged the injector and the check engine light came on (showing its not a bad connection). I swapped injectors and the problem didn't move. I knew it was something bad, either a dead valve or damaged rings.

I stopped at a friends house on the way home and used a compression tester to verify. The cylinder had about 5 psi of pressure! I was hoping that a valve was stuck open so about a week later I grabbed a head from Pick & Pull (a story in itself). I cleaned the head up and waited for new gaskets to arrive.

Look at the third valve on the bottom row


The chunk taken out of that valve was really big. Larger than a new eraser from the back of a mechanical pencil. There were no marks on the cylinder wall or the piston head. I removed the entire exhaust to shake and turn up side down and the chunk was no where to be found?!

The people at Pick & Pull are dicks and wanted to charge extra for ever single part (even 1.75 for each head bolt!) so I had to swap everything from my old head include came retaining bearings.


Now for the fucked part of the story.

I put everything back together and started to fill with water. I heard a tap tap tap under the car. It was coolant dripping down onto the newspaper. I traced it to the water pump. I assumed it was the gasket since the pump was new as of 8 months ago. I went to the local dealer to get a gasket and took the damn timing belt out again.

Filled it back with water and .... dripping again!!!! I was very careful to drain it out, dry everything thoroughly and have someone fill it while I watched. It was leaking from the damn weap hole on the pump housing near where the bearings are! I had never seen it before.

I couldnt find my receipt for the pump and of course the parts store couldnt find my information in the computer so I had to buy another one. Again I took the timing belt off.

It ended up taking me a good 6 hours but the car runs perfectly yet again

What I can say is that Im impressed at how well the car ran with only three cylinders. I must have driven 300 miles before fixing it and didnt even get a check engine light

The car has nearly 250k miles and I have driven it like I stole it every day since 120k.

One word of advice - My only guess is that some of the "ceramic coating" created by Steal Seal must have got on the valve land and caused it to snap. Steal Seal does work but it should only be used on an engine you plan to junk. If you ever take the engine apart after using it you will find the entire piston/valve/head covered in a ceramic like coating that has to be chipped off.

Because of this and other Subarus (including two dohc RS) I am a timing belt and head gasket ninja. For thanksgiving I took the engine out of an RS and replaced nearly every wear item including clutch and rear main seal.

Oh and Hi to everyone

[tris91ricer]

Nice to hear from you again, Cipher. How ya been, meng?

[ciper]

Better now. Fighting cancer, getting divorced and leaving my job wasn't easy.

One good thing I can say is that I am confident now to do any work on a Subaru except for maybe porting heads.

I had to sell my XT6 and got screwed by someone who was supposed to help with an engine swap. I gave him 1500$ and a 91 turbo legacy and all my service manuals (14 books total) and they are all gone. The turbo legacy was 1000$ plus 800 shipping so I am out 3300 + all the FSM

[BXSS]

Do you have any idea what your EGT's were?

Judging by the whiteness of the e-valves it looks like the car was running very lean.

I think you did not find more engine damage caused by the chunk of valve that was missing because it disappeared drop by drop as it melted down.

[AWD_addict]

Cool story. At least it wasn't an intake valve.

[vrg3]

It's really good to hear from you again, ciper. I'm sorry to hear about the misfortune, though, man.

Were you paying attention to the coolant temperature as this whole thing happened, by any chance?

[evolutionmovement]

Great to hear from you again! Things sound rough and I wish you the best with everything.

The exact same thing happened to my N/A a couple years ago with 247k miles. Cylinder #3, with only a slightly larger hole. On a not particularly hot summer day I accelerated to red line in the first 3 gears, as always, onto the highway and a few seconds after hitting cruise speed I started hearing an odd beat to the exhaust note. Drove fine about 20 miles back @ 80, but by the time I pulled onto my street it started shaking pretty bad. No damage to anything but the valve. I wish I had known that before swapping the engine with the EJ22T I had in the kitchen and running N/A just to get it driving as I would've just done the valve, but the little bits of metal that came out on the rubber hose I used to explore the dead cylinder made me think ring land. Too bad as that N/A engine was a real ringer (though maybe that's why the valve melted).

[ciper]

I guess it could be possible that the valve melted but I have a strong feeling it wasnt the cause. After driving so many shitty cars I've made it a habit to check the gauge cluster about every 5 minutes while driving, especially when pushing the car hard so I am sure the coolant temperature was normal while driving and when I exited the highway the overflow was in its normal range. I was also driving up the mountain with steady increase in elevation so if anything I should have been running slightly rich. Also realize this is an NA motor so boost creep or fuel starvation shouldnt have been an issue (who knows though).


I realize now that I should have removed that valve and saved it as a souvenir When I inspected the edged it looked more like a crack than melted

The white color on the valves aren't what you think. That is actually the Steal Seal material that hardened onto the valve! The stuff was about as thick as 4 sheets of paper and covered most everything except the cylinder wall.

I have to say again how surprisingly powerful the car was while running on 3 cylinders. If it wasnt for the strong vibration when idling I might now know anything was wrong until I checked my gas mileage. It didnt even though a code the entire time




I bought this car 130k miles ago for about 600. It ran well for quite a while until I started to see the signs of a leaking head gasket. I could sometimes hear bubbles in the heater core and this made me smell the coolant often, which eventually had the smell of hydrocarbons.

Since the car was so cheap I was lazy to repair it properly. Instead I bought steal seal and ran it through the engine. It actually worked! What I didnt know is that I would be plagued by a bad thermostat for many months to come and not know it, spending considerable money and time.

I drove for a while and things seemed fine. However if I stressed the engine for more than a minute it would start to get hot. What I didnt realize was the thermostat couldnt open and the engine was able to cool itself enough with air and the heater core for around town driving (guess it makes some sense if VW/Porsche engines can do it).

Eventually I got tired of carrying around bottles of water and worrying about it so I ordered the HG/Bolts/Seals etc..

I did the work with the engine still in the car (yes its possible) and got the heads back on. It was now very late at night so I decided to leave. Things got busy at work and I had to put off finishing it for a few days. What I didnt know is that my friend boxed up all the timing belt pulleys and stuck them next to his house,,, and it rained on them!

I cleaned them up and checked the bearings. They seemed good so I finished the job. The car ran fine but about 200 miles later it was obvious a bearing was failing somewhere. It quickly went from a squeek to a terrible noise. I drove back to his house and started to take the timing belt cover off. Thats when I saw the hole now cut into the front...

I was in great luck because the pulley that failed was the one that was attached to the water pump. I say this because it seized up completley and started to rotate on the bolt and proceeded to destroy the water pump. If this had been anywhere else I would have need a new block! The more amazing part was the car still ran fine lol

I had to buy a new water pump and find a new pulley. As luck would have it I recently got a legacy turbo engine from the junk yard. As a matter of fact it is the same engine I sold to Thawa (is he still on this board?). I swapped this one pulley and put the new pump.

Well again I drove the car on a trip and it tried to overheat on a hill fuck!!!! I couldnt believe that the headgasket could be bad and the water pump was good so it had to be something else. I limped home and for the next week I watched it very closely. There was no coolant leaking, the coolant didnt smell of hydrocarbons and still tasted sweet (leaking head gasket makes it acidic). After many other troubleshooting attempts I took the thermostat out and boiled it in a pot of water with a candy thermometer. At the specificed temperature it was barely opening. I ran the temp very high and it never opened the way it should.

This entire time a stuck thermo was what had fucked me. I am sure it caused the original bad head gasket which lead to everything else. When I did the HG the first time I replaced everything except rear main seal and thermostat. I didnt do the thermo because I knew it was an OE part and assumed it was still good.

After installing a new thermo I was able to drive up a near by mountain at full throttle for many minutes without a single issue. This gave me confidence which lead to the dead valve


Considering how I drive this car its amazing more hasnt failed. The saying "drive it like you stole it" was never more fitting. Even with 250k miles (1/4 of which at full throttle lol) it still passes smog perfectly and gets a combined MPG of 21 even with a torque converter that no longer locks.

[entirelyturbo]

Wow, welcome back Ciper. It's endearing to see all the OG guys coming back .

Sorry to hear of the bad times.

[vrg3]

Wow, dude.

Still, though, why would sustained full throttle cause a valve to burn/melt/whatever without raising coolant temperatures significantly? An air bubble in the coolant, maybe? Or a local overheating condition? I wonder if water wetter would help defend against something like that.

And, yeah, Subarus run really well on 3 cylinders. When Matt's (legacy92ej22t's) car was running on three I had no idea. He sensed the rhythm was off but I really thought there was some more general problem, like even an intake leak or something.

[555BCTurbo]

Major evil shenanigans my friend...


I had to deal with the same situation on my girlfriend (s/n Laura)'s 90 Legacy L...we thought it was interesting that the motor shook a lot at idle...and wouldn't hold speed in 5th gear...


But yes, it was the best running 3 cylinder Subaru I have seen (barring Justies of course)

[SemperGuard]

Wow, welcome back Ciper. It's endearing to see all the OG guys coming back .

Sorry to hear of the bad times.

OG reporting

As luck would have it I recently got a legacy turbo engine from the junk yard. As a matter of fact it is the same engine I sold to Thawa (is he still on this board?). I swapped this one pulley and put the new pump.

That engine has a story now. Not very interesting, but a story no-less.

Ciper I am very happy to hear from you. I will hit you up on yahoo or msn, I forget which you use, if you still have the same sn. If not, I'll send you a pm.

[ciper]

Oops. After writing that entire story I forgot to say why I thought the valve broke. I think a small flake of the steal seal came off and was on the sealing surface between the valve and head. After getting hammered at 10,000 cycles a minute for so long the valve finally cracked.


Running an engine with contaminated coolant is worse than you can imagine. Either running pure water, never changing it or a leaking head gasket will turn the coolant to acid. This causes cascading failures. For example -

I removed the drain from my radiator after fixing the head gasket and nothing happened. I eventually had to use a screw driver and pressure from the hose to push the red cruddy mess out of the radiator that clogged it up.

If you read my entire post you will remember the leak from the service hole on the water pump. I am sure this was from the previous acidic coolant

About 2 years after this my heater core started to leak. Many of you have no idea how hard it is to replace the heater core. If you drive a beater you are probably better off bypassing it!

I had a hose that would leak past the clamp no matter how much I tightened it. Only buying a new hose would fix it.

If I remember right I took the IAC off to clean it was very corroded on the inside (I cant be sure if this was another car or not)


VRG3: I supposed its possible I had a cooling system problem but I couldn't find any other damage to the head. Since pick & pull were assholes about charging for every single piece (even the bolts) I had to remove nearly everything from the new head except the valve/springs. When I took the old head apart to transfer parts I looked it over closely and couldn't find anything else wrong. Even the headgasket was in great shape.


555BCTurbo: I probably drove on 3 cylinders for quite a distance. Mine too was loosing speed in top gear but I assumed the loss in power was because of altitude.

SemperGuard: I still use all the same IM names, though I usually stay in invisible mode.

[legacy92ej22t]

Wow, it's great to see you back ciper. Sorry to hear life has been so rough but it's great to have you back!

[douglas vincent]

I bought my Reddevil back in 2003 (?) WITH a bad exhaust valve. Drove it a few thousand miles like that.... I just disconnected the injector. hahahahaha.

But then after I had fixed it, a year or two later, I had another cracked (but not leaking) exaust valve.

So.....

I think the Legacies CAN crack valves just due to wear... And then start to burn through. And once you start, there is no turning back!
hence the burned holes we have seen!