I've had blow-by vapor (which is mostly water) and oil coming out of my breather line since I turbo'ed my car at the beginning of this summer running at 9 psi. The compression was 195-195-195-195, wear and tear from having a 170k mile old bottom end. There had been a few times where the engine detonated (not knock/ping) because my turbo would spool faster than some of the times I could get the pedal to the ground, keeping it in closed loop, and starving it of fuel.

Well the vapor/oil coming out of the breather picked up a lot. I can make a puddle of water and oil where my breather dumps on the ground the size of a quarter of a sheet of notebook paper just idling for about 10 minutes.

I did a compression check...

190-170-90-195...

I added a capful of oil to the middle two cylinder and they bumped up to 220 and 170.

Would you rule out the headgasket being a probablity?

This sucks bad because I'm a full time student going to college off student loans, w/ no garage within 4 hrs from me. So basically what that means is that I wouldn't be able to rebuild the motor till next summer. This is my only car :(

I planned on one day building my bottom end, but not till I was either done w/ school or a summer in the future.

What's the longest anyone here has drove on two and a half cylinders?

According to the compression tester instruction manual it says if any two adjacent clinders are 20 lbs or lower than the rest, a defective head gasket is indicated.

What do you guys think?

I was going to go out tonight (first weekend after school's started), but looks like I'll be staying in.

that sux, i hope my oil coming out of the cap isn't any indication of big problems cause i'm in the same boat as you with school and loans and crap, my plan for if my engine gets shot to shit right now is to hopefully find a complete motor for under a grand to just stick in until i can rebuild, otherwise i'll be SOL, good luck with figurin somethin out.

Don't want to scare you, but I had oil coming out of my oil cap once I was turbo, until I put a brand new one on.

Sorry to hear bout that man. I blew a ringland on #4 and tried to make it for a couple months but couldn't. Was blowing smoke out the breather, dipstick, exhaust and it was just embarassing with my car all smoking out the ying yang. Eventually had to pull off the head and replace the piston/ring.
Alvin

http://www.cardomain.com/id/96rst

I am scared the same will happen to me once I am turbo...Except I have a garage here at school (apartments suck...living in a house is cheaper)

Not to sound like a jerk...but why would you boost 9psi on a stock bottom end with 170k?

I refuse to go over 6 once I get everything going.

I fuckin love your car btw. It's the sexiest white creation around!

90 psi is pretty low, sounds like a cracked piston ring land. While the engine is at idle, pull the oil dipstick out, and if you can feel a good amount of air puffing out the tube, then it's most likely a cracked piston ring land...even light amounts of detonation on the stock cast pistons can cause this..I did it to 2 of them :) If your boost gauge shows vac, you will prob notice that it pulls a bit less vac at idle as well. It should idle between 17-20 hg's. If you want a cheap fix for now, get a doner piston(LOTS of guys on here should have them) and swap it out. Pull the head and oilpan off, and pop out the bad piston. If you can, run a ball hone in that cylinder, and put some new rings on. I've done this 2 times in the past to get my by before i did my rebuild, and i didnt even hone the cylinders..just slapped in an old pitson out of another 420a. Believe it or not, compression was only like 10 psi less than the others..

haha that's awesome but even just taking the head off is a lotta work O_o but I guess if your short on funds for forged pistons that'll do the trick.

I gotta change my rings so I"ll probably be doing something similar down the road.

When you did the compression test did you notice any water or oil in the cylinders? That's how I was able to tell 2 of my cylinder had a blown headgasket on my Z. when I cranked it a geyser of water shot out of my head.

Another indication is water in your oil or muddy oil.

Did you do the wet test? Pour oil into the cylinder and see if it raises the compression? (oops I just reread your post and it did shoot up so its either ring or the piston)

Joel i have a set of used pistons, hell i have alot of them. If you pay shipping i will send some to you.

Geez, you guys are great..

Tomorrow morning I'm going to go see if I'm getting puffing out of the dipstick, and also check inside the cylinders for water/oil (I didn't think about this when I was checking the compression), and then I'll post back.

Originally posted by WickedESi
Geez, you guys are great.. Tomorrow morning I'm going to go see if I'm getting puffing out of the dipstick, and also check inside the cylinders for water/oil (I didn't think about this when I was checking the compression), and then I'll post back.

I have a set of oem pistons/rings/rods with 48 miles on them just sitting, let me know if you want them and we can work something out... and remeber, I am in alabama man.

EDIT: lol, they are in that white box next to my passsenger brake rotor in my sig pic...

Originally posted by ScreaminE
I am scared the same will happen to me once I am turbo...Except I have a garage here at school (apartments suck...living in a house is cheaper) Not to sound like a jerk...but why would you boost 9psi on a stock bottom end with 170k? I refuse to go over 6 once I get everything going. I fuckin love your car btw. It's the sexiest white creation around!

Seriously.

Originally posted by jsupetran

Originally posted by ScreaminE I am scared the same will happen to me once I am turbo...Except I have a garage here at school (apartments suck...living in a house is cheaper) Not to sound like a jerk...but why would you boost 9psi on a stock bottom end with 170k? I refuse to go over 6 once I get everything going. I fuckin love your car btw. It's the sexiest white creation around!

Seriously.

My car loved 9 psi at WOT and EGT's never went over 1400, even on a super long 5th gear boost pull down the highway. I had no knock, low EGT's, and wasn't near 300 hp, so I could have gone higher.

What destroyed stuff was my car reaching "high" boost while it was still in closed loop. I am aware not to part throttle boost, the boost just responded faster than I got the pedal down to WOT a few times and I heard/felt a loud pop that sounded/felt like a backfire coming right out of the head, and no power.

so what did you decide to do?

I ended up not even looking at it today. It put me in a bad mood thinking about it.

I'm pretty sure it's the bottom end. I'll take a look at it when I get up in the morning.

I'll probably try to get ahold of a spare block and head and building it when I have the time and money, then dropping it in come Christmas break, complete w/ an upgraded clutch, and possibly still do my Megasquirt during the break as well. It looks like, however, I would have the option of this, or get a reliable daily driver, and deal w/ the Talon later, but not both.

XtremeRS, your solution is actually looking really good to me to get me by for the time being, as this was completely unexpected, but don't I have to change the HG and deck the head each time I have it off?

Originally posted by WickedESi
I ended up not even looking at it today. It put me in a bad mood thinking about it. I'm pretty sure it's the bottom end. I'll take a look at it when I get up in the morning. I'll probably try to get ahold of a spare block and head and building it when I have the time and money, then dropping it in come Christmas break, complete w/ an upgraded clutch, and possibly still do my Megasquirt during the break as well. It looks like, however, I would have the option of this, or get a reliable daily driver, and deal w/ the Talon later, but not both. XtremeRS, your solution is actually looking really good to me to get me by for the time being, as this was completely unexpected, but don't I have to change the HG and deck the head each time I have it off?

you have to change the headgasket, and you only have to deck the head if its warped or has any divots or imperfections where it contacts the gasket... and its most likely warped so yea deck it and get a new HG

How much meat do I have to remove before my compression is too high? It's been done once, I could have sworn the machinist told me 25 mil (.025") too, but if I do it again just to swap in two other stock pistons, and then again when I actually build the bottom end, won't that be too much?

I would like to say you should pick up a 1g talon/eclipse/laser NT for peanuts and drive the shit outta it and deal with your talon later...It would be awesome to have two cars in case one breaks.

Well everytime you have the head off, its always a good idea to have it checked for flatness. Some say you can resuse the replacement MLS headgasket,but for 30 bucks, i've never even contemplated that. If you dont have any current HG issues/leaks or anything like that, then simply cleaning the block and head surfaces VERY WELL should get you by just fine. Be SURE to follow all torque specs and procedures with the head, esp when taking it off. I like to back out the head bolts(studs for me)a little at a time, in the right order. This prevents any chance of warping the head. Be sure its overnight cold before you take the head off. Take a known true straight edge to the head, to check for warpage. .004" is the max allowable. Dont forget to use the copper gasket spray on the new MLS headgasket, as this mainly helps heat transfer, but also helps fill in small block/head imperfections.

If you have already had .025" taken off the head, i prob would not have any more taken off. Just to put a new surface on a head, they usually take off a small .004", which at least I was told by my machine shop. They couldn't do any less than that, but who knows, maybe their equipment was not very sophisticated.

Joel, check email/pms!

That's a dead piston.

If you want to ghetto it, i have at least six good stock 420A piston/rod sets sitting around. Drop the pan, remove the dead one, install new rings on the used piston, reinstall, button up. It's an ugly, dirty hack, but it can work in a pinch.

Let me know if you want one.

I'm thinking I should go ahead and replace both middle ones, and all four sets of rings, I didn't try this with cylinder 1 and 4 yet, but when I added oil to cylinder 2 it went from 170 to 220 (I thought my valve seals were bad and that that was the reason my compression on the "good" pistons wasn't perfect). Does anyone know an approximate cost of stock rings?

Looks like the order of opperations for Labor Day weekend are: re-ring all pistons, hone walls, replace pistons 2 & 4, install arp head studs (so I don't keep buying bolts), slap on another mls headgasket, check the head for flatness, and turn the boost down until I have a Megasquirt and wideband.

Thanks to everyone who has been so kind to offer me a replacment piston.

EDIT: Something intresting though is that even w/ that low of compression on cyl 3 my vac has been ~16.8-19.8 depending on how long I've been driving (not neccessarily when the engine's first warm does it go to about 19).

Well, the diagnosis was dead on the spot!

The #3 piston had 7 cracks in the ring lands, it all held together thank GOD, not a single scratch in any of the cylinders. The head gasket is good and all the bearing surfaces in the motor are good. I would have a well running car back this weekend if I didn't discover my intercooler filled w/ oil (I made a seperate post about this, please use it if you have some insight).

I post pictures of the piston before and after the rings are removed (cylinder in chunks).

I would like to give a BIG thanks to Aaron (totaleklipse97) for donating some pistons to me and getting them to my door in such short notice.

I finally had some time this weekend to find a ride home and finish up the motor. I ended up doing much more than just changing out that piston, I pretty much overhauled the whole motor (had leaky valve seals, re-ringed all the pistons, timing components where due in again too). First start she runs great, not a single leak or error code :). The turbo is good, no oil blowing by the seals, ATP turbo and suiclipse were right about the seals being hard to blow but easy to let oil by under high pressure :). I have Castrol GTX oil and a Mobil1 oil filter for the 500 mile break-in, then switching back to synthetic. Thanks again for the donor pistons Aaron.

Compression seems to be dead on, vac is at 18, but a I can tell more by the low speed torque. I'm waiting to 500 miles for the rings to completely seat to do a comp. test, sound good?

I have a important question though, my timing belt seems to ride left and right about 1-2 mm, coming off the end, valve cover side, about .5mm max. I changed both bearings (tensioner and idler pulley's), everything torqued to spec, 21 ft-lb tension checked by reinserting the lock pin to test (and yes I took it back out), and the belt feels like it has the same deflection to my fingers as my old one did. I've done a few timing belts now, and haven't run into this before. There was some oil on the bearings I didn't catch, so it could be swaying back and forth a little due to the oil? I'll be degreasing the engine soon.

I unbolted the tensioner bracket from the block, and after I was finished up with the motor I saw it say in the FSM that if that bolt is removed you have to replace the whole bracket because it's coated w/ a special thread sealant from the factory. I used red loc-tite on it (and loc-tite on almost all bolts, since I have solid mounts).

Let me know what you guys think.

I took a look at the timing belt again (didn't look at the belt since I drove 4 hrs last night), and it seems like it's moving side to side only .5-1 mm, it looks like possibly it could be the water pump causing the side to side movement (it's a brand new water pump, but the gear has a very slight wobble to it). Maybe it's just not settled in it's seal yet?

Originally posted by WickedESi
I took a look at the timing belt again (didn't look at the belt since I drove 4 hrs last night), and it seems like it's moving side to side only .5-1 mm, it looks like possibly it could be the water pump causing the side to side movement (it's a brand new water pump, but the gear has a very slight wobble to it). Maybe it's just not settled in it's seal yet?

Thats prob what it is..my T belt does the same thing really, and its been fine for a loongg time now. Did you reuse your old belt, or did you get a new one? If you reuse a belt(that is still in great shape of course) you should always mark the direction of rotation so you can put it back on the same way. Dont really know if that can cause this symtom, but its what is supposed to be done. Some waterpumps are not that great quality if its not from a dealership..I think i got mine at Napa..but anyway, *slight* movement of the belt is fine.

The belt and pump are new. The water pump is a duralast brand from autozone, so I'm sure it's just a crappy pump as I replaced it using my warranty on my last autozone pump which was making noise before the rebuild.

It's good to hear yours does the same thing and is fine.

Oooh yeah starting to get my MS system going. I just bought a Zeitronix Zt-2 w/ the new shiny black anodized LCD, I will ditch (sell) my whole triple a-pillar (boost, egt, and nb02 sensors).

I'm so excited :D