gsxr-t-bag600

Whats up HT.i will try to keep this as short as possiable. I have a Turbo 92 civic hatch si with a d16z6 bored .20 over Wisco pistons, Eagle rods, block guard. stock head except stage 1 cam. Only thing i cheaped out on was the Ebay intercooler and pipping. i had it tuned at Kmod performance. It was making 276whp on 18lbs. i drove it for a week or so after the tune only getting on it a handfull of times. The car seemed as if it was running pretty rich. At times i would pull in to get gas and not get the car started back up for another 10-15 mins as if it were flooded. I went to work one day and the car was driving as its been. When i got off i started it up and it sounded like a wrx, like it was running on 3 cylinders. My egr was left open and smoke was coming from there and my oil breather port on the valve cover pretty heavy. i towed it home and did a compression test only to find that one of my cylinders was dead (no compression) the other ones read fine. I did not do a leakdown test. i pulled the head because i figured it was a bent exhaust valve and stripped the head. All the valves seemed fine, none bent. I put the head back together and set the lash. i pulled the oil pan and unbolted all the rods and that is where i am now. I havnt pulled the Pistons because i dont want to buy new rings and replace bearings if i dont have to. Since i have little experience rebuilding the block what should i do? should i pull the pistons and make sure all my cylinders are fine and rebuild the bottom end? is there anything i may be missing or anything else it could be from the info givin so far? what would you do? i dont mind getting the learning experience and pulling it all apart but it does stink that i just dropped all the money into the motor to get it built for boost, just so i can have it tuned and then it take a dump on me a week later. any help is appriciated. sorry for the book.

gsxr-t-bag600

The tops of the pistons looked good. i didnt see any marks from slap. the head turns freely as it should when opening valves and turned the cylinders a few times with a socket it all seemed smooth, but i know that doesnt tell me anything.

Turbo-LS

iTrader: (4)

Need to do a leak down test see where it's leaking from.

th3pwn3r

Worst comes to worst it won't cost you too much to get another block, especially if you're going the route of a block guard...

wantboost

iTrader: (2)

Sounds like classic ringland breakage to me.. I bet if you pull the bottom end apart you'll have pieces of piston in your hand

And yes you can break forged pistons.

Schister66

^^Be that as it may, why would it have broken? It seems like a strange solution to his problem...

Could it have been a simple headgasket failure?

NotNew

well im no expert but just by looking at the valves you cant always tell if one is bent. They can look fine and still be bent slightly. Need to do some testing or have it checked out. Its either rings, headgasket or valve issues so it shouldnt be that hard to figure out with some effort..on my Z6 3 headstuds pulled out of the block and let the head lift under boost which basically blew the headgasket, even though it didnt look bad when I took it apart it was enough to cause low cylinder PSI. Also if the head is high mileage it is possible for worn valve guides to let the valve walk around on the seat and not seal. If its has like no compression in one hole with blowby it kinda points and piston/ring problems IMO..

wantboost

iTrader: (2)

Anytime someone makes the wrx reference it's generally ringlands.

If the gasket failed it would be blowing white smoke like an insect fogger, at least that's how we blow HGs around here lol

OneBadTurboCRV

None of this is true at all... too much misinformation.

You should have done WAY more diagnosing before pulling the engine apart. To have zero compression it most likely isn't ring lands. You need to start by reassembling some parts and actually try to diagnose the problem or start posting quite a few pictures.

turbohatch96y7

iTrader: (15)

Right away I was thinking valve lash.
Did you re set your valve lash before pulling the head after the compression test?

rich7777

You could be right. Simple things first huh ?

gsxr-t-bag600

Thank you for all of your responses. I didnt do a leakdown test. I was going to bring the car to a friends that has an air compressor, but i ended up doing a compression test. I figured it was a bent valve, head gasket, or the rings. (Guess i should of waited). I rolled the valves on a table and stood them up just to make sure i wasnt physically able to see they were bent. I no thats probably not the way to tell if they are bad or not, but all looked like they open and closed problem free. They just had some carbon build up. When i set the lash almost all were within spec. The ones that wernt were .2 or so out of spec. I figured at this point it was the HG. I looked at the gasket for any spots where water could of broken through, didnt see any (but didnt rule it out)I then pulled the oil pan and girdle. I shined a light up in the cylinders and down the cylinders and turned it over with a socket. From what i could see nothing looked broken. when i ran my fingers on the cylinder walls i can feel small groves, u cant really see them just feel them. i have got as far as i did without pulling pistons. re reading my post makes me think ill be taking a trip to the machine shop in the near future lol. Thanks again guys.

gsxr-t-bag600

Do you think I should pull the pistons and see the outcome or put the head back on, do the leakdown test and go from there? or any other sudgestion?

gsxr-t-bag600

I did not set the lash while the head was still on. (before compression test) i see your point. I wish i would have. i put the head back together and set the lash and set the head to the side. I have a video of the car running before i pulled the head. u can see the smoke comingfrom EGR and valve cover. i also have some pics. if i can ever get my Email to start acting right. I will post them all asap.

wantboost

iTrader: (2)

Lash would have to be way off to have no compression.

Where are the grooves located? Skirts will normally cause a small amount of rubbing against the cylinder walls, in line with the intake and exhaust side of the bore, due to the slight rocking motion of the piston as it moves through the stroke...


A good ghetto test to see if a valve is bent is put it back in the head (no springs) and turn it. Put something on the valve seat like grease or lipstick... if the valve isnt bent you'll have a perfect circle of missing grease, if its bent it will be oblong and not perfectly round, plus you should be able to see the slight wobble

Another method is chock the end in a drill and pull the trigger. A straight valve will spin perfectly balanced while a bent one will have a slight wobble that could be seen and occasionally felt while spinning

gsxr-t-bag600

The grooves are exactly where u speak of. I had just noticed it and wasn't sure if it may be associated with my problem. The valve in the drill sounds good, i will try that. Thanks. I have been trying to upload pix, but having problems getting my photo to my email. I finally got 1 to go through but now it says error every time i try and upload, idk if the pix are using too much space but i tried to make them small. I also have a video. and watching it again the smoke that is pouring out appears to be white. When i removed my turbo manifold the same cylinder that was dead also had antifreeze come out of it. Idk if it was the way i had the car jacked up but it wasn't something that i was used to seeing.

lostforawhile

ouch, white smoke and antifreeze in the manifold say head gasket or you have a cracked head or block

wantboost

iTrader: (2)

If he didn't drain the coolant before pulling the head then it could simply be residual coolant in the head made its way into the cylinder...

But since he has the head off anyways, if it was a blown headgasket it's a moot point now since he'll need a new one

I strongly recommend head studs if you don't already have them.

gsxr-t-bag600

Please replay

gsxr-t-bag600

Yeah i was kinda thinkin that.I didnt completely drain the rad, just wasnt 100% if that was normal. Im just trying to remember all the details. Its easy to sit here and post symtoms and have people take stabs at it. Thats why id like to get that video and my pics up atleast make it a little clearer. I was able to get 1 pic to work. I hope u all can see it. Im Sorry if it is blown up. im having a lot of trouble with my computer. I have ARP studs.