Head-Gasket Failure Explaination

[Garrison]

I found a very good read on the actual dynamics as to why our head-gaskets fail, as well as tips on how to avoid it.

http://allwheeldriveauto.com/subaru-hea ... explained/ (http://allwheeldriveauto.com/subaru-head-gasket-problems-explained/)

[mlitz]

great information, and good read.... thanks

[Garrison]

Thank you, I thought so as well. Hopefully it will help people who haven't yet replaced their headgaskets to prolong or avoid having to do so.

[Wiscon_Mark]

Didn't know the trick with the battery! Good thing I have an OCD type obsession about clean battery tops.

I also read some of the comments below. Wish this guy had a shop in my neighborhood. He really knows his stuff.

[98legwag]

Didn't know the trick with the battery! Good thing I have an OCD type obsession about clean battery tops.

I also read some of the comments below. Wish this guy had a shop in my neighborhood. He really knows his stuff.

How do you go about cleaning the batter top?

[Wiscon_Mark]

They make a tool like this: http://www.harborfreight.com/battery-te ... 94450.html (http://www.harborfreight.com/battery-terminal-cleaner-94450.html)

And a spray like this: http://www.amazon.com/Permatex-80369-Ba ... 084&sr=8-1 (http://www.amazon.com/Permatex-80369-Battery-Cleaner-aerosol/dp/B000BO9J52/ref=sr_1_1?ie=UTF8&qid=1327103084&sr=8-1)

I'd recommend you wear goggles, battery acid is nasty.

[98legwag]

I assume you disconnect the ground first?

[Wiscon_Mark]

You have to disconnect both to get at the terminals. The brush part that pulls out of the terminal cleaner is for cleaning the wiring off.

[kimokalihi]

I recently sparked an external head gasket leak on the right head. I can visibly see a gap between the block and the head where the gasket is missing. I'm pretty sure this gap is not supposed to be there. I was leaking about a metal coolant tank every 3 days or so. Went to the dealership and bought a bottle of their coolant condition and dumped it into my metal reservoir and within a day the leak stopped and hasn't come back. No more smoking engine bay and burned coolant smell at every stop light. I'm blown away that this fixed it but who knows how long it will last. It's been a week and so far so good.

This is on an EJ20G from a JDM WRX with JDM Forester EJ20G heads. Leak is probably my fault for not getting the heads and block resurfaced before putting it together. :banghead:

https://sl-i.net/FORUM/images/imported/2012/02/IMG_20120123_113906-1.jpg
https://sl-i.net/FORUM/images/imported/2012/02/IMG_20120123_113919-1.jpg
https://sl-i.net/FORUM/images/imported/2012/02/IMG_20120123_113950-1.jpg
https://sl-i.net/FORUM/images/imported/2012/02/IMG_20120123_114003-1.jpg

[Wiscon_Mark]

Yes, always get the heads remachined. My guess is that it won't last very long before you'll be leaking again. Unfortunately, you may also be leaking internally (coolant into oil & vice versa) so keep an eye on the consistency of your oil & coolant. You don't want to throw a rod or something because your oil got thin.

[kimokalihi]

I've been checking it a lot. No sign of internal leak yet. If the engine goes it's no big deal. It was a cheap build anyway. Slapped a JDM wrx block together with my JDM Forester heads after the forester block blew the piston rings from detonation in one of the cylinders. Paid $100 for the block plus a stock exhaust. The new oil pump and gaskets cost way more than the block cost me. If it blows I'm ditching this stupid EJ20G and going with my spare EJ257 block and building it properly this time. It'll be back to the metro for a while.

[Wiscon_Mark]

EJ20G is one of the prized JDM motors. I wouldn't be so quick to ditch it. I don't remember all the specifics, but it's supposed to have great head flow, much better than the USDM motors.

[kimokalihi]

Oh the heads will still be on the EJ257. I don't have any other heads to use. But they'll be getting rebuilt.

[Wiscon_Mark]

That's a good hybrid motor!

[kimokalihi]

With the 257 or the 20g block?

[Wiscon_Mark]

20G heads on the 257 block!

*ahem, back on topic!* :grin: