piston rings stuck, new piston time?

[3.0 GT]

to make a long story short i was cruising for about 30 minutes then i boost up to pass a car and start blowing smoke from the exhaust and studdering. pull over, engine died and wouldnt start again.

got home and compression test showed 60ish in all cylinders. pull engine to find everything is fine except the piston rings are all stuck compressed and not springing out like normal.

when i pulled my lower intercooler pipe off about a pint of oil poured out. i am running a holset turbo with a oil feed restrictor but i was running 40w oil with a quart of lucas to keep my dying bearings alive, and i think the seal is blown and while cruising oil built up a puddle in the intercooler and when i boosted it flooded the cylinders and maybe did a mini hydrolock on every cylinder and crushed the ring lands, holding the rings in.

what is your opinion? and is it probably time for new pistons? this rebuild has litterly less than 500 miles on it.:cry:

mods:
rebuilt 7m, arp's, mhg, stock rods, pistons.
lex & 550's
holset he351
intake
3 inch exhaust
stock intercooler

 

[lewis15498]

to make a long story short i was cruising for about 30 minutes then i boost up to pass a car and start blowing smoke from the exhaust and studdering. pull over, engine died and wouldnt start again.

got home and compression test showed 60ish in all cylinders. pull engine to find everything is fine except the piston rings are all stuck compressed and not springing out like normal.

when i pulled my lower intercooler pipe off about a pint of oil poured out. i am running a holset turbo with a oil feed restrictor but i was running 40w oil with a quart of lucas to keep my dying bearings alive, and i think the seal is blown and while cruising oil built up a puddle in the intercooler and when i boosted it flooded the cylinders and maybe did a mini hydrolock on every cylinder and crushed the ring lands, holding the rings in.

what is your opinion? and is it probably time for new pistons? this rebuild has litterly less than 500 miles on it.:cry:

mods:
rebuilt stock 7m
lex & 550's
holset he351
intake
3 inch exhaust
stock intercooler

Your bearings are shot and you have 500 mi on a rebuild? Why are the bearings dying? Why weren't they replaced? Why are you breaking in a motor with 40 weight and lucas? Why are you boosting on a motor with mechanical issues? Why are you trying to drive it if its fucked up?

Whats my opinion? Buy a civic and find a good mechanic because you should not be touching cars.

 

[Suprapowaz!(2)]

I always thought rings collapsed onto pistons when severely over heated. Why would you be running such thick oil with an additive on a fresh rebuild? Why would your bearings be dying so soon?

 

[3.0 GT]

i had shit in the oil somehow and it killed the bearings and so i replaced them by taking off the subframe and the crank was scorn but it was just a I HOPE IT WORKs fix not a 100% fix. so i replaced them and just ran heavy weight oil since the crank was scored. but nevermind that what about the pistons. i dont know if it overheated or not but i dont know why it would have.

 

[lewis15498]

Dude this is not the first time I've seen a thread like this from you. Not trying to be a douchebag, but you really need to get a mechanic, it will end up costing you less.

 

[3.0 GT]

ehh, ill get it right someday

 

[Suprapowaz!(2)]

I like your persistance. Besides, doing the work yourself you save money and learn... even if you learn by making mistakes.

Well, since you have the engine out and disassembled take it to a machinist. Get that crank cut and polished. Replace bearings with the correct size. If bore is standard see if it would clean up with a good hone job. If not you might have to go oversize just a bit. I see a set of an off brand pistons with NPR rings for just under $100 to your door. They have them in standard, 0.020 (.50mm), & 0.040 (1.0mm) sizes. You can do the whole deck and mill the surfaces to run a MHG, or just check for straightness and clean to run a composite. I guess that would be the bare minimum that needs to be done. Good luck.

I also see a set of ACL rod, main, and thrust bearing set 0.010 (.25mm) undersized for roughly $120 shipped from a top seller on egay.

 

[IJ.]

My "guess" is it's detonated and broken the ring lands.

 

[3.0 GT]

I like your persistance. Besides, doing the work yourself you save money and learn... even if you learn by making mistakes.

Well, since you have the engine out and disassembled take it to a machinist. Get that crank cut and polished. Replace bearings with the correct size. If bore is standard see if it would clean up with a good hone job. If not you might have to go oversize just a bit. I see a set of an off brand pistons with NPR rings for just under $100 to your door. They have them in standard, 0.020 (.50mm), & 0.040 (1.0mm) sizes. You can do the whole deck and mill the surfaces to run a MHG, or just check for straightness and clean to run a composite. I guess that would be the bare minimum that needs to be done. Good luck.

I also see a set of ACL rod, main, and thrust bearing set 0.010 (.25mm) undersized for roughly $120 shipped from a top seller on egay.

Thanks! as fore the engine, i was planning on geetting the crank ground and the block and head were milled when i rebuilt it along with the correct thickness metal headgasket. The block is .020 over and had npr pistons in it. but i will still take the block to make sure the bores are good and get it honed for some new pistons. as for pistons since i am going to shoot for higher hp anyways, im just going to upgrade to some forged pistons, with stock(maybe shotpeened) rods.

My "guess" is it's detonated and broken the ring lands.

possibly, but detonated on every cylinder and shit on every piston? i didnt know that could happen. i was only running 12psi boost and im running 93 gas. but i guess anything could happen. i couldnt see any crack in the psitons but i guess it could have gotten squished holding the rings in place.

Dude this is not the first time I've seen a thread like this from you. Not trying to be a douchebag, but you really need to get a mechanic, it will end up costing you less.

i have rebuilt this engine before and it lasted thousands of miles but i then lost a piston from a massive boost spike and low octane gas(detonation killed the ringland on piston #3). i have also rebuilt my brothers 7m and it has lasted at ~350whp for over 6000 miles so far. i have also rebuilt the r154 which has been running strong for thousands of miles. i could go get a civic but id rather do things myself. i am plenty capable of doing things right but usually my wallet holds me back. not anymore since i have a steady job and will probably sell my dirt bike to get more cash for the engine.

 

[Suprapowaz!(2)]

possibly, but detonated on every cylinder and shit on every piston? i didnt know that could happen. i was only running 12psi boost and im running 93 gas.

Maybe your CPS moved and advanced all cylinders. That is kinda weird that all of the rings would bind like that without running really hot. Did you run low on oil? Nah, then you'd spin a rod bearing or two. Just be honest with us. We won't judge you that much more than we already do. What exactly did you do to cause this. And don't give us the 'ole, "I was just driving to bingo and gave it a little gas to get on the highway" bit.

 

[3.0 GT]

Maybe your CPS moved and advanced all cylinders. That is kinda weird that all of the rings would bind like that without running really hot. Did you run low on oil? Nah, then you'd spin a rod bearing or two. Just be honest with us. We won't judge you that much more than we already do. What exactly did you do to cause this. And don't give us the 'ole, "I was just driving to bingo and gave it a little gas to get on the highway" bit.

i was driving on the highway for about 30 minutes going to my lake house just cruising. i got behind a slow car, so i downshifted to third and took off. half way around the car it starts studdering and i look in the rear view to find a massive blue smoke cloud. i go a little further down the road and pull over and when i pushed the clutch in to coast off the road, the engine died and would never start again. oil was pouring out the air filter too. so i brought it home and checked eveything out. timing of cams, 10* btdc timing, fuel, spark. all was good so io did a compression test to find everything was aound 60psi. took the engine out and here i am.

 

[lewis15498]

You know what man, I respect you for not giving up. I repsect you more for not flipping out at my comments. I couldnt get past 500 mi and dying bearings. Just don't try to band-aid problems so you can keep driving it in the future. Sometimes its wiser to let it sit until you can afford to do it right. And don't go boosting until you know your up and running 100%. To answer your question, I would guess you need new pistons. The best decision may be to do a full rebuild. Find yourself something else to drive if you haven't already. Then do the rebuild, take your time, dont cut corners, read up before you do, and ask questions if you are unsure. You will learn more and fail less. Best of luck to you.

 

[3.0 GT]

You know what man, I respect you for not giving up. I repsect you more for not flipping out at my comments. I couldnt get past 500 mi and dying bearings. Just don't try to band-aid problems so you can keep driving it in the future. Sometimes its wiser to let it sit until you can afford to do it right. And don't go boosting until you know your up and running 100%. To answer your question, I would guess you need new pistons. The best decision may be to do a full rebuild. Find yourself something else to drive if you haven't already. Then do the rebuild, take your time, dont cut corners, read up before you do, and ask questions if you are unsure. You will learn more and fail less. Best of luck to you.

thanks a lot. i do plan on rebuilding and im just going to check and recheck everyhting when it goes back together and will probably upgrade the internals and leave the car sitting for a while so i can get enough cash to finish it once and for all.

 

[Heavy D]

i have heard lots of bad stories about using lucas in your motor oil, even worse for the turbo cars, i would look into that before you do it again just incase

 

[kingrichard]

i used lucas once after i spun a rod bearing and replaced it....at my very next oil change i didnt use it and when i started the car it was knocking on just about every cylinder at idle, sounded like an old deisel truck...lol lesson learned.....Lucas= bad

 

[3.0 GT]

i have heard lots of bad stories about using lucas in your motor oil, even worse for the turbo cars, i would look into that before you do it again just incase

yeah the only reason i used it was to tighten up the clearences which i realize now was a bad choice lol. but since im rebuilding it to spec i will never have to worry about that again.

i used lucas once after i spun a rod bearing and replaced it....at my very next oil change i didnt use it and when i started the car it was knocking on just about every cylinder at idle, sounded like an old deisel truck...lol lesson learned.....Lucas= bad

lucas=fucking bad lol