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Aw man...do I have to split the case?


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93 Loyale

 

Low compression on one cylinder + valve job = higher compression, but still not enough.

 

I am kicking myself for not doing this earlier, ahem...before the valve job, but I ran a wet compresssion test and the wet results went WAY up:

 

50 - dry

150 - wet

 

This is the one that has a serious blowby issue (chased it as a suspected blocked cat for a while).

 

Since I am a little hard pressed to find another block around here to just dump into this machine I am wondering how difficult it would be to service the block/cylinder myself? It's just the number 3 cylinder that is wrecked, the rest are fine at 150 psi and the vehicle has really low KM.

 

I don't mind buying tools to tackle this or even taking it to a machine shop (they are getting to know me now).

 

I have heard that you don't have to crack the case to get the pistons out, and you need to make a tool for their removal but would I need any special tools aside from maybe a ring press and a honing tool? Any advice would be greatly appreciated.

 

Dean

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you don't have to separate the block. it sort of depends on what the problem is.

 

it could just need new piston rings. so a hone and new rings and you're golden. there's a piston pin access port, pull the clip out, the piston pin and then it can be removed. one thing i'm not sure about is how to prevent debris from the cylinder walls and honing tool from getting down into the block.

 

if the cylinder walls are scored or damaged then you'll need more experienced folks to comment on how or whether it's fixable.

 

it might be simplest to drop off another spare piston and rings and take the block to a shop.

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I'd do all four cylinders while you are at it. It'll be like new after that.

 

I'm with grossgary on the metal/FOD from honing...not sure on how to prevent that from getting into the crank/rod bearings.

 

I was pretty careful on one engine I did but the rod bearings failed after 2 miles.

The same engine also had massive oil consumption so it may have been oil starved before hand anyhow. :shrug:

 

One engine I didnt take the pistons out, just went to BDC on each one, 3-stoned it and its a STRONG engine that burns nothing, doesnt smoke, no noise.

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I kind of like the piston at BDC idea. Another idea is to shove some paper towels in around the crank, while the oil from the hone should keep the metal from flying around. If you are pulling the motor, I would definitely put it on a stand with that cylinder straight down while honing.

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Why bother though, its not like its that much more work to split the case and the only additional expense if you don't want to do the bearings (which I would do) is a couple o rings and some silicone sealer.

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Well, I was just a little worried that I'd mess something up and shorten it's life in the process, but you are right - I might as well do a full rebuild. I pulled the engine last night and I noticed a scrape on the cylinder wall right near the top...does this mean I should get a new sleeve pounded in there? It's a little scuffed, and I can feel the bump with my finger but I can still see the cross hatching all the way down the cylinder, so the issue appears to only affect that 'ring-ish' part of the sleeve (not sure what that ring piece is called). I will attempt a ring job, but I doubt I'd be able to pull off and ram a a sleeve in by myself - machine shop once it's all apart I guess? You can see the torched bottom part of the piston where the junk was getting past.

 

Here's the pics...

post-26551-136027646917_thumb.jpg

post-26551-136027646922_thumb.jpg

post-26551-136027646928_thumb.jpg

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Technically the sleeves are not replaceable...unless you go aftermarket and spend WAY too much money. Even then in most cases the sleeves end up sinking into the block after several heat cycles and you get a blown headgasket again and have to re-deck the block to match the sleeve. Most of those cases you cant deck the block anymore because its been decked too much already.

 

WJM has been there and seen it all on sleeving subaru blocks. To get it done right costs more than your average sleeve job.

 

 

I would do a full teardown and rebuild and go 0.25 over on the cylinders. If they have not been oversized already you have two overbores you can do; .25mm and .50mm.

 

There'd have to be more serious damage than that to need to go .5mm over. I've seen worse clean up with a .25mm bore.

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Parts depends on what engine that is...SPFI/MPFI/CARB...and year.

 

But, you stated "93 Loyale" so they should be...

 

RH piston, EACH: 12013AA040 $69.73 (2 needed)

None in country, part is still active. 3 week wait time probably. Depends on JAPAN's situation on shipping and if they are in a warehouse thats cracked/flooded/nuclear contamination.

LH piston, EACH: 12018AA040 $58.98 (2 needed)

5 in country, immediate availability.

Piston Ring Set 0.25mm OS: 12033AA010 $248.62 (1 needed)

2 in country, immediate availability.

 

Or you could source aftermarket stock replacements that are 0.25mm OS. For a stock car and put together right, aftermarket tends to work fine for the average customer.

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Yeah sorry - SPFI, non-turbo, wagon, on demand 4wd, 5spd, and handsome.

 

Cool, thanks a bunch for the info. Those part numbers are for the .25mm bore?

 

Hold on...if I use bigger pistons, wouldn't I need to use different head gaskets then too? Like slightly bigger? I can see the head mating surface side being fine since it is flat around there but won't the gasket 'cylinder holes' need a larger circumference too...?

Edited by Deener
I'm dumb
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Might want to look into how much it would cost to have a good used engine shipped up to you. It might be cheaper and faster to swap another one in and just keep yours for spare parts. Cylinder damage is rare, and usually due to running out of oil or sucking debris in. Most used ea82's are going to be in decent shape.

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Funny, I just found an engine over the weekend so I drove out and pulled it. The local JY's have not been keeping anything older than Legacy's so finding an EA82 was pretty lucky. The cylinders look really good, no scuffs or dings or anything. I have both engines down to their blocks as I gather gaskets and rings and all for the swap.

 

I am guessing that some debris must have ended up in that cylinder because the damage is right on the bottom, perhaps then it toasted the ring(s) on the piston creating the huge blowby. I don't believe that the ding in the wall is enough to be leaking that much compression on its own (40-50psi dry, then 150 wet) and perhaps it's just another symptom of the underlying issue.

 

I plan on tearing the old one down to get a full post mortem and I will post some pics when it's apart.

 

Dean

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I don't believe that the ding in the wall is enough to be leaking that much compression on its own (40-50psi dry, then 150 wet) and perhaps it's just another symptom of the underlying issue.

 

You'd be surprised...

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Deener, was there a good 5 speed on that car you grabbed the engine from?

 

I might need one. The rock did a number on my tranny, which is leaking despite a big wadge of JB Weld the guys at Kal Tire put on. Runs fine, except it goes from full to add on the dipstick between Terrace and PG.

 

Rob.

Edited by robm
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