Newly rebuilt B16a Smoking

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So ended up keeping my OBD0 B16A from my crx, had the engine rebuilt and installed it into a 93 Del Sol. I had the head sent out, new valves, springs, retainers, valve guides, and valve stem seals installed, had the block bored w/ new pistons/rings installed, all new king bearings, new buddy club head gasket and arp head studs. On initial start up it ran really choppy, and eventually figured out that the map sensor had the wrong vaccumm line ran into it. What im getting is a gray/dark gray smoke out of the tailpipe, now i know thats normally indicitave of coolant getting into the combustion chamber, but, thats impossible as there is no coolant in the engine yet. Could the engine be smoking bc of the spark plugs being black from fuel bc of intially having the MAP sensor getting no vaccum? Or is it normal the engine to smoke some after a full rebuild? im just trying to figure out what could be causing this, timing has been checked, rechecked, and checked 5 more times after, distributor is brand new, already tried another known good one to see if maybe i was getting weak spark, tried using a P30 and P28 ecu, compression is 175 on all 4 cyl's. Can anyone give me any ideas at all besides coolant that can be causing this? any help would be greatly appreciated!
 
Its normal for them to smoke after a rebuild, if you put a few miles on it and it doesn't stop then you have a problem. You ran the motor with no coolant?
 
^^ +1

its burning a fluid. there are plenty of variables here, fuel inj, head gasket, floating/sticking valve(s),oil.

-I would do a compression test- make sure cyl chamber is sealed right (rings,valves, head gasket are sealed)
-If all checks out "ok" try a cyl leak down test. (by pressurizing the cyl chamber, you can change the about of psi by a dial on the cyl leak down tool, this will let you know where a leak may be, and/or letting a fluid into the cyl chamber.
 
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i ran it for a few minutes, not long enough to build up any signifacant heat, havnt actually had the chance to fill/bleed the cooling system yet, was having trouble getting it to run/idle until i figured out the map sensor problems, im going to switch to iridium plugs bc of the raised compression, and bleed the cooling system and try to drive it, hopefully its just smoking from breaking in as jizared stated, just trying to gather as many options as i can so if the smoking doesnt stop, i can rule them out 1 by 1, compression is 175 dead on across all 4 cyl's,
 
The smoke would be WHITE if it was the head gasket and coolant into the cylinder....so I sat that is not it. How many miles on re-build now? Gray smoke ...dark Gray makes me think its either settling or its running rich (Black smoke) What ECU? Chipped? If so...get a tune cuz you might be running rich with bad fuel/air ratio. Sounds like you have put some money into it and in my opinion....a tune is due.
 
The smoke would be WHITE if it was the head gasket and coolant into the cylinder....so I sat that is not it. How many miles on re-build now? Gray smoke ...dark Gray makes me think its either settling or its running rich (Black smoke) What ECU? Chipped? If so...get a tune cuz you might be running rich with bad fuel/air ratio. Sounds like you have put some money into it and in my opinion....a tune is due.

I had a blown head gasket on my first civic and the smoke was a blue-ish color and smelled sweet.
 
The White smoke is supposed to be the coolant that is burnt out (like condensation) The sweet smell may be the actual coolant rather then regular old water from the hose. Blue smoke is sometimes Oil burning out too....that would be rings or soemthing.

OP did you seat the rings well when you broke it in? I know you aren't suppose to be hard on it during break in but baby'ing it is bad too.
 
I have been told you need to seat the piston rings and should let the motor decelerate (like from 5K down...similar to down shifting) And you should not stay at a steady speed either. Always be slightly accelerating or decelerating. But eg6sir is right.....others say different. Although, I can see seating the rings being important and stagnate driving not being good for break in's. I plan on doing a rebuilt B18C with type R pistons in the next year or so....so I guess I'll get the experience too.
 
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theres literally 0 miles since the rebuild, this car hasnt even left the shop yet, im trying to get it all running good before i take it out, dont want to be left broken down, im currently on a p30 ecu w/ a p28 already out to be chipped, like i said it cant be coolant, bc theres no coolant present to burn, i also forgot to not that im currently still on NGK copper plugs, ive been advised that i need to run a colder plug bc of the raised compression, so im going to pick up some NGK iridiums on mon and throw them in as well, currently stuck inside under 24" of snow, so the whole thing is on hold for the weekend, and yes all the rings are set properly, they were set in their respective places for me by my machinist whose specialty is honda motors, so hes got quite a bit of experience with these engines
 
I meant seated....in terms of them finding their form.....when running and ready to hit those high revs and to have a motor with great compression all around and a solid motor that will live to high potential. This topic (breaking in a new bottom end) can be controversial and up for debate. There's a thin line for a break in. I have seen good results (1/4mile times) from awareness and overall car/upkeep in a brand new (and rebuilt motors). Its all up to your decision on what stance to take and, like you stated, you want to feel confident in the motors status before taking it out for the first time.

I believe your machinist placed the rings on a non-load axis part of the piston and were close to being on opposite sides of the piston (kinda like the 'Flux Capacitor' from Back to the Future lol) . I'm not speaking of the installation of the bottom end. Sorry if I made you think I was referring to that.
 
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oo ok, no i havnt ran the motor long enough to even begin the break in process, i dont plan on babying it completely, nor do i plan on beating on it, just my usual daily driving, i guess ill bleed the cooling system, put the new plugs in, and take it for a few test runs and if im feeling confident about it, ill start driving it daily
 
Just do yourself a favor and read up on people's opinions on break ins....the first hundred miles is pretty important (although even that number is up for debate lol)
 
ive been doing a bit of reading on it, theres so many different opinions on it though, ultimately ill prob talk to a few guys i know who have built quite a few motors, and see what theyre opinion is, def want to do whatever i can to protect my investment and make this thing run as strong as possible
 
your enginer is going to smoke on its first start up no matter what. you have oil on your pistons and some of that oil will get down into your header and what not......so its going to smoke. then you will still smoke because your rings arent seated yet and the hone is still rough on your walls.

get everything hooked up, Coolant lines are Verry important! how do you think your idle control works? it needs coolant to work correctly.

After you get everything hooked up, make sure you have enough oil in the engine. I would strongly recomend a magnetic oil plug to get all the metal shavings. start the engine let it run on high idle and run it above at about 2k for 5 min, stop and drain the oil. refill change your filter drive for 20 miles and drain oil replace filter and re fill. Get your engine tuned and replace your oil at 100 and 500. break in how you think is correct.
 
I and several others have always broken in my builds by starting what is written above. after its tuned i go to a place with lots of hills. Start in first take it to about 3k shift, take it to 4k let off and let the engine slow to 2k, shift easy untill 3rd then take it to 5k and let off untill you hit 2k again, only giving it 1/2 throttle max. then repeat a few times, then shift easy to 3rd slow to 3k and gun it to 5k. let it slow to 3k again and then gun it to 7k, repeat a few times and your good to go.
 
i realize the engine is pretty fresh still but 175 psi seems awfully low for a high compression b16...

i would hesitate to make any assumptions until you actually get coolant in the thing and start driving it around a little bit. if the smoke doesn't go away then you know there's a problem.
 
turns out i broke 2 of the oil rings by accident when installing the pistons, causing it to smoke like crazy, got a new set of oil rings on the way, re-install with some more experienced help should happen tomorrow
 
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