d16builder

I have a 93 civic ex with a d16z6 I just rebuilt everything is new I got a new head about a month before I rebuilt the bottom. I just started it for the first time and let it run for a while hoping the smoking would stop after the rings set in but it didn't I got it bored .50 I'm lost any suggestions on what I should check?

shotoutacc0rd

"let it run for a while"

this isn't how you break in piston rings

grumblemarc

iTrader: (4)

I'm sorry. 0.5 over?

stupidhard

of course not. im sure the procedure for break in calls for a couple passes up the street. get her up to second gear and accelerate "quickly" to about 5k rpm a couple of times. this will seat the rings.

follow the oil change schedule for break in like its your job.

-chris

d16builder

Thanks. What do you mean by oil change schedule? This is my first build so it's more of a learning process than anything.

Wdpfreak145

Yes. As in ".5mm" which is the first acceptable boring limit on stock d-series block, making it 75.5mm. Otherwise known as .020" over.

Oil change schedule. Every 3 months or 3k miles. Standard practice.

Now on to the point. Dumb question: did you purchase new pistons and rings with the proper bore? 75mm pistons and rings will not work in a 75.5mm block, in case that wasn't obvious.

Now we need to talk about what kind of smoke you're having. If you're burning oil (bluish smoke) then you probably have a hemorrhaging failure somewhere. Improper ring installation, bad valve seal, etc. If it's white smoke then you could be burning coolant and that is from coolant getting into the combustion chamber from an improperly installed head gasket. We need more information on what you've done and what exactly is happening. Pics and videos will be your witness.

FWIW, all the procedures I have read on seating new rings and such always say to take the car out at low speed and take up to a reasonable rpm and then let the engine decelerate on its own to allow downward drag to force the ring up and mate with the cylinder wall as the pistons go down, while engine speed slowly drops (engine braking). More knowledgeable people might have otherwise to say.

grumblemarc

iTrader: (4)

Just checking. I've seen dumber things.

d16builder

Ok thanks I want sure if you meant regular oil change schedule our if a new build called for it more often and I will surely try the ring procedure you gave me. Is it normal to smoke a lot before the rings are set in?

NotARaCist

iTrader: (1)

Holy ****, no, you don't change oil after 3000 miles on a fresh rebuild. Your engine is smoking because you didn't hone it. You don't have to bore it, but you absolutely MUST hone the block, or the rings will never seat. You need to pull it apart, replace the rings again, and hone it.

For initial oil, you should also use special break-in oil, not just normal off-the-shelf oil. Fill with break-in oil. Start the car, let it warm up. Change the oil, filling again with fresh break-in oil. Dog the **** out of the car for 50 miles. I'm talking WOT pulls and engine braking at all times. Best done on a dyno or track. Change the oil again, filling again with fresh break-in oil. Drive the car normally for another 500 miles. Change the oil one last time, filling with whatever oil you like, and only after that do you switch to changing oil every 3000 or 5000 miles.

shotoutacc0rd

Gnarly I'm pretty sure most machine shops should know to smooth the cylinder walls when they bore an engine. Then again some machine shops suck.

I think it's that OP cant even tell the difference between oil smoke and coolant steam, and also that it doesn't seem like he broke in the engine properly

stupidhard

there is a oil change schedule in the hames manual... I know that for sure, just not certain about the intervals.

Wdpfreak145

This right here is a more apt description of exactly what you should do when building an engine. The first couple of oil changes are VERY crutial. Also, check the oil when draining for metal shavings of any kind. If you can afford it and have access to it, it might be worth dropping your old oil off at a lab to get it analyzed. The analysis breakdown will give you a very good idea of what's going on inside the engine and tell you things you can't/won't see without pulling the engine apart.

grumblemarc

iTrader: (4)

That's for after it's built and broken in.

NotARaCist

iTrader: (1)

Holy **** no, you don't smooth the cylinder walls. That's the exact opposite of honing it. Smoother cylinder walls = guaranteed zero sealing from new rings.

That's the standard service interval. It has absolutely nothing to do with a freshly built engine. If you follow standard service interval, your rings will NOT seal correctly, you WILL burn oil, and you WILL lose power.

Wdpfreak145

This man is right. Smooth cylinder walls = glazing, which is a bad condition for those of you who don't know.

A fresh cross-hatch is always best and should be performed anytime a machine shop does aaaaaanything to a block.

Unbelievable what some of these mech-savy auto enthusiasts will spout...

NotARaCist

iTrader: (1)

Glazing from the oil, and cylinder wash from the gas. Smooth cylinders = fucked engine.

stupidhard

no sir... there is a break in oil change schedule in the hames manual... im pretty sure anyway... ive read it cover to cover on the ******* like twice.

I could be wrong, ill look in a bit.

grumblemarc

iTrader: (4)

shotoutacc0rd

I figured thats what it meant, I'm not a machinist I dont know these things. So I guess a hone means make the walls rough, learn somethin new erryday

Fliptard

I would hope you also put another NEW head gasket on? Once it's torqued down, it can't be re-used.

Wdpfreak145

Honing is the process by which the machinists go through and using special tools etch a fresh cross-hatch into the cylinder walls. This helps the oil travel up and down the cylinder wall in the oil control ring of the piston. Here's a good example.

NotARaCist

iTrader: (1)

Not a bad example. It would be a great example, if it wasn't for all that surface rust

shotoutacc0rd

How do people take care of rust like that? Bring it back to a machine shop?

Wdpfreak145

Yeah I saw that after the forum blew the image up. Got it from google.

You can buy your own honing tool from an auto parts store and it can be done at home. They can be attached to a drill and use spring-loaded stones and a specific type of oil or what they call the "dingleberry" hone tool which looks like well... a bunch of dingleberries (think "sheep **** pellets embedded in wool") on tensely twisted steel.

grumblemarc

iTrader: (4)

Aren't you supposed to be building an engine?