Motor Help...Smokes!

[Simon]

Hey,

Ok, my car smokes. I got my head rebuilt a couple months back, and have put about two miles on the car since. It sat six months before the head replacement. It has all new gaskets, what could it be? Also flames shoot out the exhaust pipe, which is still only a header no full pipe yet. I am thinking bad bottom end, I hope not though because that will throw my budget down underground and my roll cage will have to wait and it will be a mess. Thanks!

Simon
www.simontibbett.evaluand.com

[JeffYoung]

In a British car, this would be normal.

Seriously, what color smoke? Volume? Does it decrease after idling for a while? Increase with more revs? Give me (and the others) a bit more description and we'll try to help.

If you just had the heads redone, you would immediately suspect rings if you have a heavy bluish (oil burn) smoke. If it is white, you're mixing coolant and water somewhere and I'd worry a bit about head installation. Black and you've got a mixture problem of some sort.

[Simon]

Hey,

Its not black so we know that. I think it may decrease a little after running a while, I let it idle for twenty minutes yesterday and got the motor warmed up and slammed the pedal down, no smoke until I let go then the usual smoke comes out. I think its white more then blue but a little blue, I cant really tell. Where would be a good place to start this at?? The car will not overheat, if the coolent is messed up, how do I fix it. I have water in the radiator right now as I dont drive the car yet and we put that in, would real coolent help? Also what about using a different oil, and my PCV valve is not connected, its clogged up, but the wierd thing is before I put the new head in, the guy that had it before me said it didnt smoke, and I never saw it smoke, he is a family friend so he is not lying. Thanks for the help!

Simon
www.simontibbett.evaluand.com

[JeffYoung]

You should be able to tell if it is oil smoke or coolant/whitish smoke. Does it smell like oil burning? It would be very bluish.

If it wasn't smoking before, it could be:

a. Ring got stuck from sitting.

b. Head job done incorrectly and you have oil getting past the valve seals.

c. Head installation done incorrectly, and you are burning coolant off somewhere.

Probably the thing to do is a leak down to determine where the leak is coming from. Have you noticed a drop in coolant/water (running just water should not hurt it short term, could screw up the water pump seals without lubricant long term)? There doesn't necessarily have to be oil in the water for there to be a head gasket issue.

I'd run it for a while, and see if the coolant level drops. If not, then do a leak down and see if you can figure out if you are losing compression in the valvetrain or in the cylinders.

How much smoke are we talking about? Many, many guys are out there running around with some smoke. Part of race car life.

Jeff

[Simon]

Ok I will look at all that, its not that much smoke, but not a little bit, you cant see it moving, I dont know, the coolent has not gone down at all since we filled it up, its still at the top just about, and the motor stays cool.Thanks!

[John Herman]

Since you didn't redo the bottom end, it may be something simple like oil/coolant/gasket pieces burning off which inevidibly fall into the bores when the head is removed. Some of it probably leaked into the rings, and at a worse case, the rings may be stuck a little. You would probably be okay to just run it. I'm assuming this was a high mileage engine. Just so you understand what you've done, you have a nice tight sealing head on a not so tight sealing piston ring/bore package. This engine may be doomed to burn a little oil and smoke a little until you do go through the bottom end. At a minimum, check/change the main and rod bearings. That way, you won't ruin your new head through a bearing failure, while you're waiting to redo the block.

[jhooten]

The engine sat up for a long time so here is my $.02, take it for what it is worth.

First use a good quality engine flush in the oil following the directions on the container. Then when you change the oil subtitute a bottle of Marvel Mystery oil for one quart of the engine oil. However before you put the MM in the crank case pull the spark plugs and put a teaspoon full in each of the plug holes. Leave the plugs out and crank the engine for about 15 seconds, let the starter rest and crank it again. Then put the plugs back in and start it. It will smoke like the dickens for a few minutes till all the oil burns out of the combustion chamber. Let it idle until it comes up to normal operating temp and then another 15 to 20 minutes to let everything work.

If the rings are stuck from sitting up there is a good chance this will free them up. If it works it will save you a rebuild. If it doesn't your out about $20 for the oil and flush and a little of your time.

[JohnRW]

You're too young to smoke.

Originally posted by Simon:
...and my PCV valve is not connected, its clogged up...

How is it "not connected" ? Is it just dangling there in the breeze, or did you plug it off ? If so, you may be building excess crankcase pressure, which could blow oil up past the rings on an intake stroke.

Hook all them doodads back up, and see if it still smokes.

[Simon]

Hey,

Thanks for the help you all. I dont smoke my car does . I never have smoked and never will sadely my car cant say the same. The PCV hose is clogged and it was broken in half when I got the car. Thanks and happy holidays!

Simon

[racer_tim]

I would just add a line from the PCV valve to a catch bottle. JohnRW has a good point. With out some kind of blow by system, the pressure will build up and since you didn't do the rings on the rebuild, that's most likey the problem.

On my VW, I need to run both a crank "breather" and a head "breather".



------------------
Tim Linerud
San Francisco Region SCCA
#95 GP Wabbit (Bent)
http://linerud.myvnc.com/racing/index.html

[joeg]

If you don't breathe a motor, oil (not just oil smoke) will come out of every where (including the dip stick tube.) As a matter of fact, you can actually "reverse" the seals in such a situation, meaning the whole motor will need tear down and rebuild.

Did we ever determine whether the smoke was oil smoke or coolant smoke?

[Simon]

Hey,

The smoke is oil no doubt. Also I noticed if I keep flooring the gas while at sitting still, it will start smoking and back firing, my timing is pretty off to a point, I will get a timing gun for christmas . Thanks! Could timing lead to any oil smoking problem?

Simon

[Simon]

Hey jhooten could that method of basically burning the old mess out hurt my motor at all? I will try it but dont want to make it worse. Thanks!

Simon

[jhooten]

I was taught that by an old school ASE certified Master Mechanic and have used it on several occasions with great success. The worst that has happened was fowling an questionable set of spark plugs.

Most receintly was on a 5MGE junk yard motor in my Supra. Smoked when I put it in. Did the flush/treat and no more smoke. Got me through my first school without a black flag.


Marvel is great stuff and Walmart carries it now.

[This message has been edited by jhooten (edited December 25, 2003).]

[Simon]

How long does it work? Also I have $302 from Christmas money, what should I get to fix my motors smoking problems? I am going to drive it on the street first to make sure it wont go away after a while of driving. Thanks!

Simon

[racer-025]

Simon,

Just some advice for the future. Anytime you decided to rebuild the cylinder head, thats a good time to remove the pistons and take a look at em. Especially if its a questionable engine. The block can stay in the car (if its a Honda were talking about). Since the head has been removed anyway, its not much more work to remove the lower exhaust & oil pan. Then unbolt the rods and pop the pistons up and out. Then you can take a look at the bearings, rings & the carbon build up on the pistons. You can also clean the ring lands and re-ring the pistons if you wish. Its not much more $$$ for rings & an oil pan gasket. Just my $.02.

[jhooten]

If the smoking is caused by the rings being stuck and it works the rings loose it will last until the rings are worn out.

And if the oil is getting past the valve seals the Marvel will help to condition them and could stop that source of oil in the combustion chamber. But surely those seals were replaced when the head work was done.

[Simon]

Well I did take the oil pan off and looked at the bottom end through there but didnt take anything off, it was very clean and I did not see any build up or anything. I also of course replaced the oil pan gasket after that.

Simon