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brewtide

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Discussion starter · #1 ·
Hello,

Been a while. Sadly, I'm 99.9% certain the 2000 Aero wagon has eaten a piston. Compression 1-4 as follows: 190, 180, 165, 60.

Lots of smoke out tailpipe (and, er, dripping oil... =), lots of pressure out crankcase, etc. All signs of doom, it's prettymuch a given.

So, It's at my parents, it never ran 'out' of oil, I caught it before and heard NO crazy sounds: So I'm hoping the following:

Cyl walls are right pretty.

If this is the case, I'm curious as to what people think of the following options:

1) Take apart, put in used b235 piston w/ new rings, run for rest of season, go from there.
2) Bite the bullet, order a set of forged STOCK bore pistons, hone cylinders, and hope the new rings all seal up nicely.

I fear I (may) have other cracked pistons, considering, but I also fear a bad ring-seal if I do not bore the walls. I've not taken it apart at all, but I'm about out the door to go take the head off and start the process.

Also, it just snowed 4 inches last night, and I'll be doing this work in November, in Maine, in a dirt driveway, building character the whole way.

JP suggested dropping the pan before the head, in order to have enough clearance to get the pan out since the upper motor mount would still remain. I'd personally rather pull the head, and then somehow jack-up the engine enough to get the pan out, later. Is this possible? I've never had to go down this route -- Never really wanted to in the beginnings of winter, either =)

Cheers, Just looking for tips, and suggestions of what you would do, and why. Money doesn't grow on trees, but I do have enough to pay all bills and buy the forged things and all required new gaskets and conrod bearings.

car: 2000 9-5 aero wagon 5 speed, t7 suite modified stage 1, 2.5" custom exhaust cat back, no cats, t5 cams, etc.

Thanks,
Benjamin
 
#2 · (Edited)
It probably doesn't matter a whole lot, but I'd go with JP's suggestion and pull the pan first. Once the heads off the lifting lugs are gone, so then like you wrote you're jacking from the bottom, or looping straps around it, whatever.

I did a light hone in-car and put some JE's in, it worked out okay. Got to low 160's compression which I wasn't crazy about, but didn't use oil. Then the car lost the main seal on the accessory side while I was tuning for a track event the next day...and ran low on oil, so it ended-up that it didn't matter a whole lot.

Regardless, you're talking a lot of work. Having done it, in the future I'm always going to pull the engine and take it to a machine shop for a proper cutting/hone. Given the weather if you pull it at least you could do the teardown/build inside somewhere. Like your kitchen maybe.

Image
 
#4 ·
You could always just put a strap between two if the head bolts threaded into the block to lift from the top - it's wasted effort pulling the pan to inspect, it's probably easier to pull the head to check it in the first place.

That's a tough call, but I'd probably try to just get the whole thing out and not try to build it outside in the open in the driveway too, there's too many things that could go wrong.
 
Discussion starter · #5 ·
Appreciate the feedback; I didn't listen, but JP supported me. Head is off, bore looks absolutely fine. Was a gasket failure next to what I believe is an oil port bottom right of cyl 4 (4 was the oiled one)... But I'm not sure I want to believe that dropped the compression to 60.

So, I've decided on pistons, etc.

HOWEVER: Being half retarded, I snapped my timing chain guides. Yes, both of them. Plus side, my tensioner was fully extended anyways, meaning, I had to be ignorant of that fact, or fix it, but, now, my task list has grown.

Has anyone done one of these in car? At least now, I do not have a head in the way, but it still looks like a pain in the ass. I've never done timing on any of my saabs aside from a head swap (I can retime, I've just never done the timing cover, etc.

Tips, suggestions? Pulling it at this point is NOT an option considering where the car is located: It's between scrap the entire car, or be hardcore and get it done before the dreadful weather sets in.

So, tips on doing the timing components when the block is in the car? Much appreciated, I know it can be done, I'm just looking for suggestions and pointers on the tasks: IE, what *has* to come off, what can stay, etc, etc.

Cheers,
Benjamin
 
#6 ·
Easiest by jacking it up, remove passenger's front wheel and wheel well liners, crank pulley & belt, drop oil pan, remove timing cover. Use Nick's balance shaft chain tensioner blanking plug and delete the balance shaft chain.

Not horrible to do in the car, but not super fun if it's on the ground, it'll be a lot of time clamboring around on the ground.
 
Discussion starter · #7 ·
Drew,

I'm pretty dedicated when it comes to 'fun' climbing down on the ground; It's like my second home. So it is plenty possible then? Also, I hear rumors of massive vibrations in the 235 w/o balance chains... Should I worry, or should I run 'er like that?

Much appreciated; I've been reading that I have to push the engine sideways to get things done; Is this the case? I'm really clueless about what exists under that cover, but seems I won't be shortly.

On the plus side, the oil pan was coming off anyways...

Sigh.
 
#9 ·
It's really only noticeable at idle, and you usually get more vibration from shot motor mounts and worn out serp. belt tensioner. It's not noticeable when driving.
 
Discussion starter · #10 ·
I ordered the part from GS in case the balance components are absolutely shot. Jp, being the awesome dude he is, said he had some good 'spares' if need be as well. It's a case of getting in there and poking around now.

Ordered pistons too; Next few days brings conrod bearings, headgasket (set), headstuds, timing chain guides, sealant, and anything else I am forgetting. Oh, have to check my current PCV update, because now is the time to swap that around too, it seems, if it is not current (I never keep up on those; I just change oil on time).

Wish me luck; The race is on to beat winter + pay the bills + buy parts. Thanks for all of the help thus far, I'm sure I'll have additional questions.
 
#11 ·
DrewP said:
It's really only noticeable at idle, and you usually get more vibration from shot motor mounts and worn out serp. belt tensioner. It's not noticeable when driving.
Click to expand...
I agree but man that system is nicely done ( engineered well) except to save money any power gains are not worth it in my book to have a high power 4 that is balaced and with balance shafts in place is really un-real, reving to 6000 at a stop and no vibration shocks me ... well done saab
 
#12 ·
Agree, I will keep it in all my cars, but on a budget build it's usually better to remove worn out balancer components than to leave them in there lest they get rattly.
 
#13 ·
mike saunders said:
I don't know how you did it, but the brushed stainless steel appliances match nicely with the milled block surface and the nice gray chain.

Slap a glass top on it and it's a table....
Click to expand...
Thanks Mike, that's exactly the look I was going for :)

I still say pull it, there's so little room in there to work. Good luck though!
 
Discussion starter · #14 ·
Drew in Houston said:
Thanks Mike, that's exactly the look I was going for :)

I still say pull it, there's so little room in there to work. Good luck though!
Click to expand...
Thanks, but pulling it really isn't an option where the car is now located, and thus far, the weather is manageable. JP suggested lowering a side of the subframe (passengers, obviously) to make it a better task.

Tomorrow I am taking the oil pan off; and then getting to the cover, time permitting. If not, Sunday will bring the cover removal.

Pistons shipped from GS today, eeuro order was placed for all new timing stuff, head gasket kit, con rod bearings, etc, etc, etc.

Thus far, a 'cool' way to spend almost $900. I'm locked in now =)

I'll keep you informed of progress, cross your fingers for me.

(This also means, assuming it gets back up and running... ahem) that the wagon is now going to become the 'project car' starting next spring. I will buy a cheap daily driver, and build the wagon from here on out. Seems silly to do all of this work otherwise.

Cheers,
Benjamin

PS. Ordered the balance tensioner block off plate; But May just retain balance; I'll see how 'eh' they look upon removal.
 
Discussion starter · #15 ·
Update: Piston #4, the suspect low compression event holder was absolutely cracked down the entire piston, twice over. Multiple (6+ ringland fractures), multiple (8+) ring fractures in both top rings. Moments away from absolute shattering.

Oh, and the cylinder bores are all 100% mint, with blatent cross-hatching showing on every cyl.

PHEW.

Tomorrow brings timing cover removal; Wish me luck

I'll try to post a picture of the almost shattered piston. The top looks absolutely fine.
 
#16 ·
I pulled a timing cover from the side in a 9-3. Possible, but not easy. You will want to get the engine over as far as possible and do it from the wheel well. The hardest part is getting all the accessory brakets off from the rear of the engine that bolt to the timing cover.
 
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Discussion starter · #17 ·
Thank you. Short message, drinking!

I've loosened half of the subframe already. I've debated how to do about it. Engine hanging off a nice OAK support beam. Tranny mount off. Debating how to go about gaining room. Sliding over, and lowering passengers side is the decided route. Crank pully free'd already (battery impact for the WIN).

Tired, drinking and eating halloween candy.
Onto the attack tomorrow; Luckly, weather has been NICE since the random snowstorm.
 
Discussion starter · #18 ·
Alright, off to attack the timing cover.

Engine is supported now via 'support beam' and the only mount currently attached is the rear mount ; It seems I am to 'remove' this mount via the 3 bolts that hold the mount to subframe, vs the 1 nut on top that holds engine to the mount. I'll see how to play it.

Head is off (obviously), oil pan was set back up into place for the night with a few bolts (dirt driveway + wind, not the best 'clean' situation, so I button up at night)

I'll check in here around noon to see if anyone else has more suggestions; Hopefully, by that time, the timing cover is in my hand. Then it's wait for parts to start to show, Tuesday timing, Thursday Pistons.

Hell, it *could* be running by the end of next Sunday assuming the weather cooperates and I get to poke at it (cleaning surfaces) a bit every day after work.

I'll admit, this much work is SLIghty intimidating.
 
#19 ·
Good luck sir, if you weren't in Maine and a little closer to central Mass I would stop over to lend a hand.
 
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Discussion starter · #20 ·
Cover is off. What an absolutely unfun process of jenga and removing, well, everything. Waterpump off, alternator off, it just kept tying into the stupid timing cover.

Thanks for the heads up; Now a week of cleaning surfaces, etc. Next weekend brings parts arrival and reassembly.

PS. How far should the balance chain tensioner be extended? It's wayyyy out there, and the chain still has a little slack in it. .. Maybe I will balance delete; I did order all new guides, but one may not be coming.
 
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brewtide
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