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TomRhere

IDing EA82 blocks

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Got a few EA82 engines here, most are disassembled. Got them thru various trips to Members houses.

 

I have what I believe to be 2 carbed blocks, and I'm fairly sure in that deduction.

 

Currently in process of cleaning another block up for reseal and install in my Wagon. But I'm thinking it might be a Turbo block vs. an SPFI block that I was thinking it was.

 

Here's pic of the piston top;

 

005.jpg

 

Besides the squarish dish in the piston top, the bung for the knock sensor is tapped. That makes me think it's a Turbo block.

 

Am I correct on that thought? Only seen one Turbo engine, and that's been some 6-7 years ago.

Edited by TomRhere

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Looks like turbo pistons from memory....though  I think I have plain mpfi and NA blocks with the threaded hole in place for the knock sensor. All mpfi blocks have a baffled inspection plate behind the flywheel / flexplate for an extra crankcase vent that exits near the knock sensor thread

Edited by jono

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Hmmm. Makes me wonder now.

 

Pic of piston top is from engine that came with the '88 Wagon when I picked it up. Engine was disassembled down to the short block and we tossed it the back of the Wagon. Heads that came with engine are N/A EA82, and I got the SPFI intake also. Wagon is definitely wired for SPFI.

 

1st EA82 engine I've been around that's had the threads in it for the knock sensor other than the 1 Turbo model I helped reseal way back when.

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Non-turbo pistons.  As mentioned, the MPFI blocks (both NA and turbo) have a crankcase vent tube rearward of the knock sensor.

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Ok. Well there's no vent tube that I can see. Haven't pulled flywheel yet to see if that plate is back there, I do know what it looks like...

 

Do know piston tops look nothing like the ones from the '92 parts Wagons SPFI engine. Those have the valve reliefs in them, no squarish dish, arrow pointing to the front along with the "UP". That engine is sitting at the work place so no pics of it. Going to bring it home tomorrow, get pics then.

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Edit:  See next post for how the overheat indicator works.

 

Pretty sure that is an overheat indicator.  If the head gets too hot, the adhesive softens and the marker drops off, voiding the warranty on the engine work.

 

The crankcase vent is large enough that if it was there you would see it.  Pretty equivalent in size to the camcover vents.

Edited by NorthWet
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Pretty sure that is an overheat indicator.  If the head gets too hot, the adhesive softens and the marker drops off, voiding the warranty on the engine work.

 

The crankcase vent is large enough that if it was there you would see it.  Pretty equivalent in size to the camcover vents.

If that is what it is, then it's good to know that it never got hot enough.

 

And there is no large vent on the block.

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I believe the overheat indicator itself melts.

It has the appearance of being aluminum itself, so if it were to melt, I think the engine would have started to melt also.

But that's just my thought on it.

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Those things are usually an aluminium washer with something like, if not, solder. I tested one out years ago ona Kroll heater and watched it suddenly shimmer, go shiny and melt out - just like solder does.

OK, Not turbo pistons , have forgotten what they look like. Just running out to an 86 carb block , was in my Nov 86 make date EA82 L Series Touring Wagon with carby - it has the threaded hole, just no vent pipe behind it - the hole is there waiting to be drilled out

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If i were to guess i would say you have a carb block. I remember the turbo pistons being much more dished in the oval part, and the spfi would only have the valve reliefs.

 

The mpfi would have the breather on the top of the crank case. otherwise, cab and spfi block look the same.

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I believe the overheat indicator itself melts.

I stand corrected. :)   My previous post has been edited to reflect this. 

Edited by NorthWet

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Pics of the '92 EA82 SPFI engine;

 

92EA82SPFI1amp2clys.jpg

 

92EA82SPFIpiston.jpg

 

Again, a pic of the EA82 piston top that came with the Wagon, SPFI parts were included, but engine was torn down to the short block.

 

005.jpg

 

Pic of known EA82 carbed piston,

 

006.jpg

 

So 3 different piston tops, 1 is known carb, 1 is known SPFI. 1 is supposed to be SPFI, but I can't prove that, came with the '88 Wagon.

 

I be confused....

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More piston difference pics, '88 SPFI piston on the right, '92 SPFI piston on the left.

 

skirts.jpg

 

tops.jpg

 

wirstpinarea.jpg

 

Then,,, I found tis on the '92 piston for #3,

OhSnap.jpg

Bummer......

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Well, it is only good for such things like ....an ash tray !

 

This time, my viewer showed me the heat tab - al I can see is the glue at the back of it, heat tab centre has melted out from the looks of things !

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Aftermarket piston for EA82T 1.00mm oversize

 

buc7.jpg

Uploaded with ImageShack.us

 

Side view, may see round oil holes Ivan has mentioned the later WRX 2.0 pistons are better for the round holes rather than slots

qhw.JPG

Uploaded with ImageShack.us

These are TK or TiK pistons  QS9000 ISO 9002 I scored a few years back and not needed yet !EA82's been too good :)

Edited by jono

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Thanks for the pics of the Turbo pistons Jono. Much appreciated......

 

Definitely a deeper dish in those compared to the pistons I have here.

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Jono,

 

I've looked long and hard at your TIK piston. It looks to me like it may be for an EA81. The shape of the valve reliefs and location, the size and location of the dish. But, I could be wrong.

 

Doug

Edited by Quidam

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Definitely labeled and sold as EA82T, may also be interchanged with EA81T I wonder ? Being aftermarket they often need to take shortcuts to keep different part numbers down. I have rings running in my 1.00mm overbore EA81 - packaged as Volvo rings !

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Yes, I've seen that with old EA piston rings. Once you go that big on the bore standard V rings fit. Another thing here is your ring width. The drilled hole Ivan was talking about in particular, diagonal from the oil ring recess directly into the top of the piston pin bore. But sure, the slot is weaker than the holes I believe.

 

The two engines don't share the same compression height, 81 and 82. An EA81 piston I measured sat like .040 below an EA82 deck.

 

Tom, never seen that dished piston. Have two carb blocks though but haven't checked them out.

 

On a practical side rule of thumb for instance. This motor for every ..010 difference in head gasket thickness comes out to about .1 CR increase or decrease. I'm thinking those might be 9:1 carb pistons. Just some thoughts.

 

Doug

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@ Quidam,

 

Interesting info you posted. I'm still learning these Subaru's, and haven't really tore into the engines this far. Only one carbed EA82, and one EA82T reseal from the head gaskets out on both. No real comparison there.

 

The piston to deck height you mentioned is apparent in these two engines, I didn't mention that earlier.

The '88 dished pistons do sit below the deck some, where the '92 pistons seem to be more flush with the deck.

I have no real way to measure the difference.

 

Kinda wondering now, what the pistons in the two ER27's I have here look like........ I recall reading on here, or the XT6 site, that those pistons are the same as the SPFI EA82 pistons as far as comp ratio goes, 9.5-1.

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Whoa...!    I sure hope the pistons in my  88 SPFI wagon doesn't have any stress fractures. :blink:

 

Cracked piston skirt on #3 probably goes with the head with the melted heat tab. That should melt around 260 degrees F and the adhesive holding the tab is supposed to melt around 350 degrees F.

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Aftermarket piston for EA82T 1.00mm oversize

 

buc7.jpg

 

Uploaded with ImageShack.us

 

Side view, may see round oil holes Ivan has mentioned the later WRX 2.0 pistons are better for the round holes rather than

These are TK or TiK pistons  QS9000 ISO 9002 I scored a few years back and not needed yet !EA82's been too good :)

SubaruEA81TITMPistons_zpse65404ef.jpg?t=

Ebay pic of EA81T ITM.

 

Jono,

 

FYI, the turbo piston for the 82 sits about .017 above the deck. Valves are canted and the cut in the piston is cut on a diagonal, where the EA81 are straight on and I would think a flat bottom on the valve reliefs in the pistons.

 

But I'm still confused about your pistons and that one of Tom's too. Only one seller on ebay for TIK and only for Honda. I have a carb block sitting in a buggy with the heads off, least I was told it was a carb block. The pistons look like SPFI. If it's a carb block I'd expect the piston to sit like .050 down in the bore. I don't think that's the case and now I wonder if someone swapped in a SPFI block. That buggy hauled rump roast with a DR 5 speed and only weighed about 1000 lbs. Any way, you all have any thoughts? Later.

 

Doug

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