Smoke screen out my tail pipe... ('95 4.3L 4X4)

[vballfun]

Was driving about 40 minutes away from home the other night when it started pouring.. and we were on a new slick black road that had poor drainage.. after hydroplaning a little I decided to engage the 4hi just for a few more tires of traction (and slow down a bit).

After got off that slick road I disengaged 4hi down to 2hi... about 5 minutes later it looked like I was driving in one of 007's cars that had a smoke screen option. In my rear view mirror I was puffing out large billowing clouds of whitish-blue smoke. This only lasted for about 20 seconds.. then went away.. until on the way to work the next morning.. drove fine all fluids checked out ok work drive is about 20 mins all interstate. 15 minutes into that drive the same thing with the smoke happened again.. for about 20-25 seconds... and again on the way home.. but not until about 15 minutes into the drive.

checked fluids again .. and looks like I'm leaking oil into the engine somewhere...

so my question is.. what is the best way to diagnose where the leak is? Is this a head gasket kinda leak? or is that usually just coolant? I look under the hood when it is smokeing out the tailpipe and see nothing smoking under in the engine compartnment. all internal.

Any ideas?

p.s. I just replaced the starter week before last wednesday.. and the day after that my radiator cracked on the oil coolant tank side so replaced the radiator thursday. Was running fine til this past thursday when said smoke cloud started appearing.

235,000 miles... and my primary mode of transportation.

[OverBoardProject]

The 4.3L is well known for it's bad intake manifold gaskets, so that's where I would start to look. I don't know what the best method of testing them is.

[biv343]

A cooling system pressure test should help ID if it's an intake manifold gasket, at least it did with mine. Does the oil look like a chocolate milkshake?

White smoke usually indicates coolant in the combustion chamber - blue is typically oil. With 235K, it could be a number of things or a combination of things.

I'd probably start with the cooling system pressure check - might not be a bad idea to to a cylinder leakdown test as well.

[vballfun]

I think I read somewhere on the forums that you can rent a cooling system pressure test kit from autozone... and I'm assuming its something that hooks into the radiator cap?? I will try that cause I am losing coolant somewhere and it's not on the driveway and i don't see any steam from under the hood..

no clue what a cylinder leakdown test would be.. i'll start paging through my chiltons...

I just added a quart and a half of oil today.. and about half a gallon of coolant.. and everything was topped off a week ago.

oh.. and the oil didn't look like chocolate milkshake.. just regular darkbrown ready for oilchange oil..
-vballfun

[vballfun]

hmm I just went down to start the blazer and it didn't want to start.. ( I'd just replaced the starter week before last).. starter was engaging but sounded like it didn't want to turn the crankshaft... tried a few times and it finally turned over and started... now I'm really starting to worry.

[biv343]

I think you can get a coolant system pressure tester from Autozone using the "rent a tool" program. If not, most any garage should be able to do it for you.

A cylinder leakdown test involves pressurizing the cylinders one at a time, having a pressure gage on the cylinder, and seeing how fast it loses pressure. Loss of pressure can indicate a blown head gasket, bad valve seats/valve seals, bad rings, pretty much anything internal. If you notice a significant pressure drop between neighboring cylinders, it could be a head gasket. Either way, you're tearing into the motor to find the cause. If it holds pressure, then you can rest assured there aren't any problems with that cylinder. You can make one fairly easily - your Chitons book should explain how to make/use one. I used that test last fall on my 85 S-10 - found the number 4 cylinder wouldn't hold any pressure - turns out the exhaust valve was shot. The head was cracked also, which explained my loss of coolant. That was a different engine than what you have - don't want to scare you.

At 235K, I'd suspect rings and/or valve seals to be the cause of the oil loss problem, unless it's obvious that it's leaking 1.5 quarts in a week. The coolant loss could be anything from freeze plugs, heater core, head gasket, water pump, intake gasket, etc.

Either way, do a pressure test on the cooling system and let us know what you find.

[vballfun]

I will locate a coolant system pressure tester this week. Thanks for all the info. I will read up in my chiltons. I just checked my oil again after running it for a bit after having filled it up.. and it isn't black it's kinda like coffee with a little bit of cream in it.. so that could be that chocolate milkshake look you are talking about.. the 'milkiness' is very subtle... gonna have to compare it to gf's oil to see if I'm just 'imagining' it due to power of suggestion

[rlith]

Originally Posted by vballfun

I will locate a coolant system pressure tester this week. Thanks for all the info. I will read up in my chiltons. I just checked my oil again after running it for a bit after having filled it up.. and it isn't black it's kinda like coffee with a little bit of cream in it.. so that could be that chocolate milkshake look you are talking about.. the 'milkiness' is very subtle... gonna have to compare it to gf's oil to see if I'm just 'imagining' it due to power of suggestion

Stop driving that truck. You have coolant in your oil. You're going to run the risk of killing your lower bearings..You entire description shows this.

Drain the oil, pull the intake, spray everything down with brake clean, pour a quart of oil over the crank, reinstall lower intake, prime oil pump (important!) finish filling with oil, (with new filter) Run for 10 mins to circulate the oil and any other crud, do another full oil change...

[OverBoardProject]

Originally Posted by vballfun

starter was engaging but sounded like it didn't want to turn the crankshaft...

This sounds like a Hydro Locked Cylinder to me. That's when 1 or more cylinders are at least partly filled with water or even oil.

With that in mind I'd say you might just have a fried head gasket, that's letting the water fill a cylinder.
There was probably a valve partly open which allowed the water to escape.

edit, running the motor with a hydro locked motor can bend valves and cause a lot of additional damage. I wouldn't even try starting it until it's fixxed because even the starter can cause some damage.

[blazes9395]

Originally Posted by OverBoardProject

This sounds like a Hydro Locked Cylinder to me. That's when 1 or more cylinders are at least partly filled with water or even oil.

With that in mind I'd say you might just have a fried head gasket, that's letting the water fill a cylinder.
There was probably a valve partly open which allowed the water to escape..

Thats the first thing I thought when I heard this. Oil and coolant loss indicates an internal engine problem. Could be an intake problem, but it wouldn't explain the heavy oil loss/consumption. Could be your guides are leaking, but at 235k putting fresh heads on it will only stress out the older bottem end (rings, lower bearings), as better sealing of the heads. Does the oil get dirty(black) fast after oil changes? Do you notice any blow-by? Start the truck, take the oil fill cap off and see if you have any bad blow-by. Look underneath the cap, is it clean, or dirty/milky brown. Pull the PCV valve out, and observe again. You could also throw a vacuum guage on it too and see what you get also. For sure though, leakdown test is needed to sdee whats going on in the cylinders. At 235K I really hate to say it, but sounds like the engine is just tired.

[vballfun]

Had two coworkers take a look at it today and they are both saying there's no coolant in the oil (it's just regular dirty oil) but there is definitely a water leak in the system.
Not sure if I need to do the coolant system pressure test if I know there is a leak somewhere... but I am going to flush the $##!# out of it tonight and get a head kit and take upper intake et all off and replace gaskets etc..

Friend also suggested taking both the heads to a machine shop to resurface them cause they will do the lifters and all that stuff (<-technical term) in the head for me for around $100... (I don't have the tools for that.. spring compressor etc)

[OverBoardProject]

If you get new valve guides installed at the same time it'll be a re-built top end. I'd seriously look into a re-built engine since like blazes9395 said your bottom end is probably warn out as well.

There are 1 or 2 members that might have good used motors for you
Try sendng DMBrisket a Private Message and see if he still has his.
heres his personal profile
http://www.automotiveforums.com/vbul...oster&t=570124
Tell him Overboard sent you.
I only have a 2.8L available, which won't fit.

[Markgc]

Where did you get your new starter motor from? Some of the Advance Auto etc cheap ones are really junk. My Blazer one was intermittent out of the box and the Cavalier one fell apart after a year. I stepped up to their OEM tested brand and have had no problems since.


Mark

[vballfun]

Starter was from Advance.. whatever one comes with a lifetime warranty.. cause I used that warranty to replace it. Are you saying that some of the ones Advance sells don't have enough 'oomph'? cause I could hear the sollenoid engage and it just sounded like it didn't want to turn the flywheel.. or that the flywheel was just reallly hard to turn so didn't turn over the engine.

btw happy 4th everyone.

[Markgc]

The first starter motors that I bought from Advance Autos came in a plain white box and they were not very good - not rebuilt properly. I took them back and got a more expensive one that was tested to OEM specifications.


You may have a faulty starter motor or you may have a hrdro lock problem as described by OverBoardProject but it could be a faulty starter motor. I just wanted to make you awate of the possibility. Just because it is a replacement starter doesn't necessarliy make it not a starter motor problem. You won't know without investigating further. It is something to keep in mind. I would deal with your main problem first and then come back to the starter motor issue after that. Advance Autos are quite good at changing starter motors on warranty - I suspect that they know that they are crappy units. I took the Cavalier one back after a year. it cranked so slowly that I had trouble starting the car when it was hot. It made visiting a gas station a hit or miss situation. They changed it and I upgraded to a better model.


Mark