So I finished my rebuild:
D16 engine
CP pistons 9:1 75.5
Eagle rods
ARP head studs and rod bolts
New OEM D16Z6 head gasket
New seals everywhere
Head & Block resurfaced

I torqued the head studs to 80N/m in three equal steps with ARP lube.

At first the engine strated and ran fine, idled smooth, for about 3 heat cycles and one drive.
Suddenly it began to idle rough and white smoke coming out of exhaust tail pipe.
I saw small bits of oil floating on top of coolant in radiator, and a thin white layer on oil cap.

I've been taking a look at the top of the head studs, and it seems like some of the studs sit a little higher the the others. Maybe I didn't bottom them down enough before torquing.

What do you guys think the problem is? Is it right to redo one stud at a time, bottom it out, and retorque?

Any input will be appreciated!

 

I'd try retorquing the whole head, chances are if that happened with one, their may be others.

 

Is it ok to loose the nut, bottom out the stud and torque it again, one at a time?

 

Compression test the cylinders.

 

No it is not okay to loosen one and tighten it then do the other.

 

Update:

I came back from the car now, tested few things:
Compression test: Cylinder 1 - 150, 2 - 175, 3 - 165, 4 - 153
Find out that all 4 plugs are equally dark black
Took spark plugs wires off, one at a time, while engine running. All of them made the same effect on the engine.

I'm thinking that the white stuff on the oil cap is either ARP lube stuff, or caused by humidity from inside the engine, because it set for a while before I started it for first time, with dizzy off, which left an open hole for humidity.

In rad there are tiny bits of oil floting, and it's probably oil reside which left in oil passages from the build.

I've disconnected all berather hoses from the intake.

What the heck can cause oil fouling in all 4 cylinders??

It's leaving me thinking it can only be pistons rings on all cylinders are bad, or all valve seal are bad?? I paid carefully attention to any detail while building the engine, and I can't think of anything wrong i've done.

The only thing I didn't touch was the head, I left the job to the machine shop.

Please help me, I'm getting really frustrated now. Thanks!

 

Did the machine shop change the valve stem seals?
You did use new piston rings and broke them in right?
If so. Did the machine shop gring the valve and the seats?
The compression range is too far apart if it was all done correctly.
Flush the coolant and change the oil and see if the white film and oil in radiator re appear.

 

Hey, I added pics for my previous post, take a look.

Machine shop stated for replacing valves seals, grinding valves and seats and doing pressure test for the head.

As for the piston rings, I haven't had enough time for breaking them in. All this bad stuff started only after one drive. My only worry is the oil I put in. It's 5w-30 valvoline mineral oil, which people let me know is good from breaking in the engine. It feels really watery, and I'm not sure it's ok for my build.

BTW the P2W is .004 inch.

 

You haven't had enough time for breaking in? You realize it takes less than 5 miles to break in the engine, right? Why did you lower the CR? Are you running a basemap, or a stock ECU? I already know it isn't actually tuned.

 

The rings should have been broken in before any drive. First start of the car it should've been broken in.
Try doing a leak down test to pinpoint where he compression is going.
Replace the plugs as well.

 

Sorry, but I can't understand. What do you mean by saying brake in? How should I break in the rings?

It's a D16ZC SOHC, running everything stock for now, except for walbro fuel pump and aeromotive FPR tuned for 3 bar pressure at idle.

Tried running it on stock P28 map and crome gold stock map. The afr readings are 9-10, but I guess it's the oil making it running rich?

 

Should probably read up on break in procedures when rebuilding an engine....

 

Is that what you mean:
https://honda-tech.com/tech-misc-15/...edure-1672379/
?

What happed is after a small drive all the problems came, and I didn't know if it's right to drive the car like this or not. I didn't want to make any damage to the engine. That's why I'm asking for your opinion now. Is that normal that the plugs foul like that, even if break in haven't done right? Anyways everyone has it's own break in method/opinion, So I don't really know what to do. Some say go hard on the motor from it's first mile, others say baby it :S

 

fixed

 

Tune it

 

I had a small *easy* drive with the car.
Now I'm thinking of it, the spark plugs remained from my last turbo build, bkr7e-11. It's probably too cold for stock motor. I'll put some 6 grade heat plugs, take it to another drive and see what happens..

 

Did you hone the walls for the new rings or just threw new rings in there.
Since you haven't broke in the rings. You might want to try it.

Hold rpm 2500 for 20 minutes.
Drives to 60mph and let off the gas and let the engine slow down to 30mph then give it has and go back to 60mph then back down to 30mph. About 10 times do it.
Just drive it normal. Don't baby it or abuse it.
Then change the oil in 500 miles but I wouldn't step on it till 1k miles.

And you used old spark plugs for a new engine. LOL.

 

Drive it normal while hitting the rev limiter, don't bounce off of the rev limiter. Keep it in gear when letting off of the gas.

I believe that was the way. Also yes if you didn't hone the cylinder walls this could also be the issue of the rings not breaking in properly.

For the spark plugs to be completely black that means something wasn't right and as a member said, get a proper tune

 

OK, thanks guys. I'll be putting some new plugs and try what you say. As for tuning it, it's just a stock setup for now. I'll slap a turbo on it soon, then get a proper tune of course.

 

So low compression on a stock tune?

"Calling all experience tuners"

Is this possible to run like this? i forgot what the stock compression was for the D16X motor.

 

It supposed to be 9:1 comp which is pretty close to the stock 9.2:1.
Are you reffering to my comp test values? Is that really to far from stock so it's crucial to retune stock base map? As I know, stock ecu running in closed loop in order to get stock afr values.

Correct me if I wrong.

Btw I do hone the cylinders and put new piston rings.

 

So you are planning on putting a turbo on it and it's even running properly?
Don't mean to sound like a douche but you should get it running correctly first before you do anything else or think of it.

Is it still idling rough and blowing smoke?

 

I had a turbo on the car before rebuild. Now I put the new rebuilt engine&tranny and swapped all other parts to original ones in order to make sure everything is right with the car before putting the turbo again. So it's very important for me if you ask.

Update:
I put stock spark plugs in, revved the motor from 2.5k-4.5k rpms while heating up, went on a 30km drive, accelerating to 100kmh then leaving the gas while in 3th gear, and repeat over and over again. No white smoke noticed after this drive.
I hope everything is good now. Thank you guys for the help, I really appreciate it.

 

Glad
to hear its running better now! Youre welcome.

 

It will run, but generally superrrrr rich, and like a piece of donkey poop.. A lot of unburned fuel will be left behind...