Coolant smoke in exhaust

[General23cmp]

Trying to get an old 230 running, and I believe I have coolant vapor from my exhaust. Hoping/assuming a head gasket, I went ahead and swapped that. I feel good that it was done correctly (clean, flat, even torque, etc). Compression is also decent and even, but not like a fresh build would be…good enough. After it runs about 30 seconds, it starts bellowing smoke. Smells like coolant to me. The oil looks clean, and the coolant looks clean. My best guess is a crack in the block, but just enough to get in the cylinder and out the exhaust and not enough to mix with the oil. I haven’t had to add any coolant yet, but haven’t ran it a ton. My only other guess is that it might be burning residual coolant that was in the exhaust prior to my repair. If so, it would eventually go away. I haven’t been running it for long periods as it fills the shop with vapor. 
 

What are some common areas I can check before going in very deep? Suggestions?

 

I have no doubt this was why the truck was parked. Engine sounds and seems to run well. I flushed the block and radiator to give it a good shot on cooling well. All exhaust pipes seem to be getting as warm as I’d expect them to, and the outer two are similar and the inner two are similar (I believe I have fire in them all). 

[Dave72dt]

These engines seem to like being retorqued a couple times after initial installation and may be all that's needed.  I'll assume you had the head checked for flatness before replacing the gasket.  If you haven't and you've retorqued a couple times, a removal and flatness check and magnaflux may be in order.

[General23cmp]

Just now, Dave72dt said:

These engines seem to like being retorqued a couple times after initial installation and may be all that's needed.  I'll assume you had the head checked for flatness before replacing the gasket.  If you haven't and you've retorqued a couple times, a removal and flatness check and magnaflux may be in order.

I didn’t have a machine shop verify flatness, but I have a calibrated bar that is used for that. All seemed good on flatness with a feeler gauge. 
 

Good point on retorque as it’s now been through a couple of heat cycles. I planned to do it after the last run when it cools. 
 

One thing I’m going to look into is whether coolant may have got into the intake when the head gasket failed/replaced through open valves (I drained the block, but due to clogs, it didn’t drain well) and made a small mess. Considering the smoke smells like coolant and I have only put straight water in the engine after flushing the engine and radiator (just for testing purposes), it could be leftover coolant prior to the repair that needs to evaporate out or be cleaned up. I’m going to remove carb and see if it’s wet inside manifold, too. I’ve been afraid to run it too long. 

[Los_Control]

A shot in the dark, I have seen some engines burn coolant off and takes a good 45 minute to 1 hour before the engine actually dries out.

Cast iron in a way is like a sponge and will absorb moisture over years of non use ..... you run em and warm them up it burns off and never accumulates.

Some engines seem to be worse then others.

Couple years ago I installed a V6 in a Dodge caravan, the engine had been sitting for 10+ years .... took almost 1 hour for it to clear up.

 

I first started my 49 Dodge up, it had been sitting for many years also. I pushed oil into the cylinders and rotated it and worked it for a couple weeks before starting it.

I had Blue smoke, black smoke, white smoke ..... I fumigated the whole neighborhood from my driveway.

 

That took awhile to sort out, found I had a clogged cooling system and could not let it run for long and had to fix that first.

Now it still smokes a little but I really think it just needs to get out on the road and driven and most of that will go away.

 

I'm just suggesting the first thing I would do in this situation, get it running. Be sure to have a accurate oil & temp gauge connected .... then let the engine run.

Get it in the driveway or open the doors .... whatever you have to do just let it run. Monitor the temp and oil.

Then after a hour or so .... see how it is doing. .... I would have done this before changing the head gasket .... nice to have a fresh gasket though and know you can pop off the head for access anytime you want without frozen bolts.

Edited August 5 by Los_Control

[General23cmp]

3 minutes ago, Los_Control said:

A shot in the dark, I have seen some engines burn coolant off and takes a good 45 minute to 1 hour before the engine actually dries out.

Cast iron in a way is like a sponge and will absorb moisture over years of non use ..... you run em and warm them up it burns off and never accumulates.

Some engines seem to be worse then others.

Couple years ago I installed a V6 in a Dodge caravan, the engine had been sitting for 10+ years .... took almost 1 hour for it to clear up.

 

I first started my 49 Dodge up, it had been sitting for many years also. I pushed oil into the cylinders and rotated it and worked it for a couple weeks before starting it.

I had Blue smoke, black smoke, white smoke ..... I fumigated the whole neighborhood from my driveway.

 

That took awhile to sort out, found I had a clogged cooling system and could not let it run for long and had to fix that first.

Now it still smokes a little but I really think it just needs to get out on the road and driven and most of that will go away.get it running ....

 

I'm just suggesting the first thing I would do in this situation, get it running. Be sure to have a accurate oil & temp gauge connected .... then let the engine run.

Get it in the driveway or open the doors .... whatever you have to do just let it run. Monitor the temp and oil.

Then after a hour or so .... see how it is doing. .... I would have done this before changing the head gasket .... nice to have a fresh gasket though and know you can pop off the head for access anytime you want without frozen bolts.

Thanks. I’m hoping a good run will help it. I had a stuck valve that wouldn’t budge. So the head had to come off before running it any period of time. 

[Los_Control]

Nothing wrong with that at all .... I kinda wish I did that to mine also.  .... Just not knowing if I have a broken ring or heavy scratches .... just a good inspection I would sleep better at nights. Same time a few years later and compression is all good in my mind, so it is going ok.

 

Letting a engine sit is like the worse thing in the world you can do to them.

It takes a while for them to get back into condition and seal up after a long sleep. .... Every engine will have it's own stumbling blocks to get past.

Some never recover.

 

I have watched videos of starting old flathead Ford V8's on a engine stand. After running a bit, you actually see water dripping out of a exhaust manifold.

The block has a internal crack in the water jacket and impossible to fix.

It is possible you have something like this going on ..... the only way to tell is to let it run and see if it clears itself up.

[Robert Harrison]

I also like the idea of re-torqueing the head its always a good idea.  Also it takes a lot of energy to convert water to steam so I can see warm-up taking some time considering everything being cold etc.  Things you can do to at lease partially trouble shoot if the torque does not work:  You could purchases a chemical radiator fluid tester Mr Gasket used to make one you put chemicals in it an it tells you if you have exhaust in your coolant.  If by running it and torqueing the head does not work maybe you have a fracture in the exhaust ports area.  You could pull the manifolds and pressurize the system cold and see what turns up?  I'm thinking you are probably ok.  Good luck let us know how it goes please.  Bob Harrison

[Los_Control]

There is no doubt you re-torque the head bolts .... is suggested 3 times.

 

I equate it to wiping your arse ..... You wipe it 3 times to find out 2 times was sufficient

When the bolts no longer move, you are done .... Is suggested 3 times at different intervals .... if the 3rd time and 1 bolt moved a hair .... I'm going to wait and do it a 4th time at a later date.

 

Modern cars, often the head bolts are not re-usable. You torque them and the bolts stretch and do not move.

It is not needed to come back and re-torque them again. .... Our old vehicles it is required.

 

Modern engines not required .... our engines it is required.