So I had this EA82T head redone by a machine shop.  Just took a close look at it before installing, I noticed this (circled in red) in the exhaust port, looks like a crack but I am no expert in this area. 

 

Is this the spot where they normally crack?  I put this pic out on a Subaru FB group, some said crack others said casting mark.  What do the experts here think?  

 

 

that looks like a death sentence - seems to me they usually crack in the middle of that ridge, though i guess the crack doesn't have to propagate the same way every time.  

can you get better lighting and angle facing up into that possible crack area? 

Edited June 29, 20205 yr by idosubaru

its odd.  This "crack" is oriented toward the cam side of the head.  I dont see any coolant passages in that area, and the shop says they pressure tested it.  Not really sure what to think.

What about in the middle of the divider between the two ports - just to the right in the first picture - that's not a crack is it?
Do the valve seats have the typical EA82 cracks between them? 

If it pressure tested fine and was going on an EA82 I'd say just run it.  But an EA82T....I'd be a little more cautious on. 

Do you know the history of this head? If it had behavioral issues that relate to cracks, you should be concerned.

I have done a few builds EA82 and T with various visible looking cracks that machine shop say checked out in the vacuum test, even paid more for their hot test, still ran fine.

No one is going to guarantee you won't have problems.

X-ray time !

I would run it, but might be a bit shaky if it was the family holiday tourer. Use a twin core radiator, ( from an EA81 if needed)to keep it cool

Further to what Steptoe says above, ensure a decent cool down before shutting off the engine. 

You want those heads to be as cool as possible to avoid any cracking. 

To me, it looks like a small imperfection in the casting. In the exhaust port you can see the cast seam coming down the port to the middle of the divider. 

Cheers 

Bennie

if it was mine i would do a mild port on it and see if that crack would buff out

that casting looks nasty

Edited June 30, 20205 yr by ferp420

Can always be welded.

1 minute ago, john in KY said:

Can always be welded.

That’s a band aid. Won’t last for long and will no doubt result in a larger crack around the welded section. 

Cheers

 Bennie

I decided to run it.  The person who sold me the heads (longtime subaru guy)  said the car they came from ran fine and didnt loose any coolant so he thinks they are fine as well.

 

Luckily, the old heads do not appear to be cracked other than the normal one between the valve seats, I will probably get those done in order to have a spare set.  

Edited June 30, 20205 yr by Scoby4wd

On 6/30/2020 at 11:47 PM, Scoby4wd said:

I decided to run it.  The person who sold me the heads (longtime subaru guy)  said the car they came from ran fine and didnt loose any coolant so he thinks they are fine as well.

 

Luckily, the old heads do not appear to be cracked other than the normal one between the valve seats, I will probably get those done in order to have a spare set.  

Helps ward off old Murphy showing his ugly face when you can be prepared like you propose

Just to follow back up here, so far so good with these heads.  Pretty sure it was just a casting mark at this point.  I dont seem to be losing any coolant and she is running good minus the boost cut which is not related.

If I had something like that, I'd use some way to feel if it was raised like a casting mark, or recessed like a crack.  Some blue die, permanent marker or something then wipe it off.  If it leaves a line, it's a crack.  Like a ghetto magnaflux.  Glad to hear it's running good. 

I actually have another rebuilt EA82T head with a similar mark.  Maybe I will try that and see what happens.

That's a crack. Whether it occurred during manufacture or later when it was running is anyone's guess - probably from cooling when it was cast. The EA82T heads are prone to cracking into the cooling jackets though if pushed hard. I wouldn't run them particularly hard. Anyone that has attempted more than 150 WHP from the EA82T has not had it last long. They just weren't up to the task. Properly setup and monitored though they can last a decent amount of time at stock power or slightly over - 120 at the wheels for example. The biggest problem is now the lack of parts and the frustrating complexity of the whole assembly compared to an EJ that can quadruple their performance with ease and are much simpler overall without the tendency toward ticking lifters, cracking heads, etc.

GD

23 hours ago, Scoby4wd said:

Just to follow back up here, so far so good with these heads.  Pretty sure it was just a casting mark at this point.  I dont seem to be losing any coolant and she is running good minus the boost cut which is not related.

Thanks for letting us knew.  That’s not like any cracks I’ve seen in EA82(T) heads and I assumed the worst. 

11 hours ago, GeneralDisorder said:

That's a crack. Whether it occurred during manufacture or later when it was running is anyone's guess - probably from cooling when it was cast. The EA82T heads are prone to cracking into the cooling jackets though if pushed hard. I wouldn't run them particularly hard. Anyone that has attempted more than 150 WHP from the EA82T has not had it last long. They just weren't up to the task. Properly setup and monitored though they can last a decent amount of time at stock power or slightly over - 120 at the wheels for example. The biggest problem is now the lack of parts and the frustrating complexity of the whole assembly compared to an EJ that can quadruple their performance with ease and are much simpler overall without the tendency toward ticking lifters, cracking heads, etc.

GD

Frankly I plan to keep the car stock so I should be fine.  If not, I have two other sets of heads to replace these.  One set has one head that shows a similar crack/mark, the other set are GenII and dont seems to show any cracks or marks in this area.   

According to the shop they were pressure tested and its on the side facing the cam tower, which I dont think has the water jacket nearby but I could be wrong.

Edited December 23, 20205 yr by Scoby4wd