smoke from engine, Bronco II

I recently bought a 1990 Bronco II 4x4 (2.9L V6) for the winter. One of the problems it came with was a significant oil leak. I had the engine resealed by a dealer. After that, they told me their tech thinks the radiator is leaking. I decided to have them leave that alone.

When I drove the vehicle home, the engine still had white smoke flowing up from around the exhaust manifold. It doesn't smell like the burned oil smell from before I had it serviced. This only occurs after the engine has warmed up. It is not characteristic of dew or condensation that is evaporated as the engine starts.

In a different thread[1] someone suggested that coolant from a radiator leak that is could be what's burning. Based on that suggestion and the comment from the dealer about a radiator leak, I installed a new radiator last night. Since then I've driven that vehicle only about 12 miles total, but after both short trips I still saw the smoke from the same area.

I will be monitoring the coolant level over the next couple days to be sure that the new radiator and the old hoses aren't (still) leaking. I also wonder if perhaps the smoke is some remaining fluid from the old radiator's leak that hasn't yet burned or washed off. Is this possible or reasonable?

Someone else[2] suggested that "[the] modulator valve (external on the transmission) can leak and suck in tranny fluid to the intake". I looked through the Ford service manual and can't find mention of any such valve. Does it make a difference that my vehicle has a 5-speed manual transmission, not an automatic?

Any suggestions as to the cause and what I should be looking for?

-D

[1] message in alt.autos.ford [2] message in alt.autos.ford
Reply to
Derrick 'dman' Hudson
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If the smoke is coming from the engine compartment, it is an external problem, likely oil residue on the exhaust and/or engine, and will take some time to bake off.

If the smoke is coming from the exhaust pipe tip, and the engine uses radiator coolant without a visible leak, then you may have a blown head gasket, cracked head, or cracked cylinder.

My 90 Bronco II uses coolant...and gurgles considerably when it gets hot. I suspect a head gasket or cracked head, but it's been doing this ever since I got it 3 years ago with no change, so I'll keep on driving it as is...it's a great commuter car.

As far as a vacuum modulator being the cause of your particular problem...it's not...manual transmissions don't have modulator valves...and I'm pretty sure the

90 BII auto trans doesn't even use one.

Good luck!

Gerard

Reply to
geewhiz

-snip-

Unfortunately, it would seem you have bought someone else's trouble. Bronco IIs are known for their problems anyway, and I would suggest you think about selling it, or trading it for either an Explorer, or other small-to-midsize SUV (dont get a large one, they're really too heavy to actually be useful as an SUV)

Chuck Burns

Reply to
Chuck Burns

I did. If I had known that beforehand ...

I didn't know that until now. What about Rangers from the same years? They have the same engine and almost identical frame and front part of the body.

At this point I'd have to get almost $5K to break even. :-(. Apparently it wasn't worth much prior to the service I had done it. Now it's usable, though. (I also have a 4x2 pickup, but that would be terrible in the winter)

Out of curiosity, though, why is an Explorer better? (I mean the early ones, not the newer ones) The early ones look just like the Bronco II except the body in the back is different. The new ones are a whole separate design.

Thanks,

-D

Reply to
Derrick 'dman' Hudson

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Yes, I lifted the hood and saw the smoke wafting upwards.

That sounds good. I drove 10 miles around town tonight and didn't see any smoke (though maybe the lighting wasn't as good; but that wasn't a problem before). The smell wasn't strong. I think I was basically just smelling the temperature. Time will tell :-).

No, this was under the hood, not at the back of the vehicle.

I better not have any bad gaskets! (not after what it cost to have the engine resealed)

I hope not. The shop didn't mention anything like that when the resealed the engine so I think this is less probable.

It will be nice to become familiar with this vehicle. I bought it with the understanding that it was usable and would get me through at least one winter. Instead, it needed ~$2K of service to pass state inspection and another $1.5K to seal up the oil leak. I added another $150 for the radiator to try and clear up the smoke issue and to ascertain that the smoke isn't indicative of a more severe problem. It's definitely a different perspective when you have a vehicle and are already familiar with it and the quirks and slight problems it has. I haven't been able to drive this one much yet. (well ~200 miles before I took it in for inspection, and only 20-30 since getting it back)

That's good to hear. The guy I bought the vehicle from had it for 3 years as a commuter vehicle. He has a new-ish Expedition now instead. (I think it was an Expedition. It's a Ford, bigger than most SUVs but smaller than the Excursion and not a full-size truck type.)

Ok, that explains why I couldn't find it in the shop manual (even in the auto trans section). That other thread, if you read it, didn't give particulars as to what sort of engine or transmission people were talking about. At least I don't have to mess with the transmission yet. (that's something I've never done before)

Thanks for your information and confirmation!

-D

Reply to
Derrick 'dman' Hudson

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Head gaskets are not typically part of an oil leakage fix...they seal the heads to the engine block, and usually don't leak externally.

snip

You're welcome!

Gerard

Reply to
geewhiz

in article snipped-for-privacy@dman13.dyndns.org, Derrick 'dman' Hudson at snipped-for-privacy@dman13.dyndns.org wrote on 10/28/03 6:33 PM:

Maybe a good engine compartment cleaning or a steam cleaning would help you locate the source more easily. Hopefully its nothing serious. I drive an 89 Bronco II...the valve covers leaked once before, although you could definitley tell the oil burning oil smell on that one. Doesn't sound like your problem. The Felpro Blue rubber gaskets solved that problem for good.

Keep an eye on that coolant, you definitely don't want to overheat those 2.9 heads. Also, check at

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or
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for additional help, lots of good guys there.

Reply to
Jason Carter

Derrick 'dman' Hudson wrote in news:lde371- snipped-for-privacy@dman13.dyndns.org:

Very unlikely that a radiator leak could get on the manifold.

The smell of burning oil dripping on a hot manifold is unmistakable. However, equally unmistakable is the sickening sweet smell of ethlene glycol (antifreeze) leaking.

Unless you are using that pink or orange coolant, you should smell that smell.

It is possible for a head gasket to be blown so that water leaks outward, but it's not common.

Reply to
donutbandit

A cleaning would definitely be good for it. I haven't heard of steam cleaning an engine before, only carpets in the house. Where can I learn more about that?

:-).

Yeah, the valve covers aren't leaking any more. (2x "gasket cover vlv rocker arm" at $16 apiece on the parts list from the engine resealing)

I haven't seen any more smoke yet, so that seems good!

Thanks for the additional resources! (google indicates that the correct address for the second site is

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btw)

-D

Reply to
Derrick 'dman' Hudson

Oh, ok.

Well, I'm not seeing any more smoke yet, so that's good.

-D

Reply to
Derrick 'dman' Hudson

A modulator valve is used to modify pressure to control shift feel in an automatic transmission; no such animal will be found on a manual.

You state that the 'smoke' is rising from the exhaust manifold; barring a significant exhaust leak, be it bad gasket or crack (which would be very apparent), the source would not be from combustion end gasses, but from a substance (oil, trans fluid, etc.) burning off the cast iron. A coolant leak of sufficient volume to cause noticeable vapor, in addition to leaving puddles on the driveway, would produce steam with a sweet, almost rancid odor. Perhaps the next course of action should be washing the manifold and head pipe at the carwash with a pressure sprayer and the 'green' tire cleaner. (engine should be *cold* to prevent any risk of cracking manifold, and take caution not to blast electronic components.). After rinsing, running the engine may produce steam for a short time as water is flashed off. If the smoking continues, further investigation is obviously in order.

And > I recently bought a 1990 Bronco II 4x4 (2.9L V6) for the winter. One of

Reply to
Marky

Derrick 'dman' Hudson opined in news: snipped-for-privacy@dman13.dyndns.org:

If you continuously have this "white smoke" sounds like something around the engine is cracked.... Do you smell that sweet antifreeze odor?

Dont overlook "freeze" (casting core) plugs on the block... a pinhole may spray coolant on the manifolds.

Have a cooling system pressure check done....must be done with engine cold.

No you have no modulator on a manual shift.

Reply to
Backyard Mechanic

It's been about a week since I put the new radiator in. No more smoke since the night after the replacement. I think I can declare this problem solved. Thanks to everyone who provided suggestions and ideas!

Someone emailed me off-list saying that these 2.9L engines have a history of cracked heads. I don't know for sure whether or not mine are cracked, but I'm not seeing any more smoke in the engine compartment. The engine is quite loud, and perhaps cracked heads could add to the noise. (this 2.9L V6 is quite a bit louder than the

4.9L I6 in my pickup)

I think that's what it was. It smells different when burned than it does in the jug :-).

That's a good point. I should find out where those plugs are. It doesn't seem important now, though, since I haven't seen any smoke in the last 350 miles.

I haven't accurately checked the coolant level -- the vehicle was on a hill in the driveway when I marked the level on the reservoir -- but while sitting on level ground now the fluid level and pencil line make a nice-looking X mark as if no fluid has leaked out since the radiator change. I don't have equipment to check the pressure, but it appears to be operating correctly now.

-D

Reply to
Derrick 'dman' Hudson

Cracked heads mean an internal crack...coolant leaking into the oil or combustion chamber, oil leaking into the coolant or combustion chamber, or some combination of the former...nothing to do with exhaust leaks.

Under normal circumstances, the radiator is to be filled to overflowing, cap reinstalled, then the coolant level checked in the overflow container. In a perfect world, this works if the radiator holds a vacuum to suck the coolant back in as the engine cools off. If there is a problem in the engine or a leak somewhere, the overflow system won't work. No matter what, you should check the coolant level at the radiator cap before starting the engine once a week or so to make sure there is still coolant in it, because it could lose fluid from the radiator while the overflow is still full, and you'd never know until you burned the engine up.

Gerard

Reply to
geewhiz

Could you please shorten (or define?) your line length just for little ol me? ;) (good information, BTW)

Alvin in AZ

geewhiz wrote: Under normal circumstances, the radiator is to be filled to overflowing, cap $ then the coolant level checked in the overflow container. In a perfect world$ if the radiator holds a vacuum to suck the coolant back in as the engine cool$

Reply to
alvinj

Hey, not a problem! Is this better? 72 characters per line...ford, mercury, lincoln, etc...hope this is better...It's hard to believe how difficult it is to type stuff when you have nothing to say and you're just trying to check line length!

Gerard

Reply to
geewhiz

Looks good. :-).

geewhiz wrote:

Right. The leak I had was, apparently, in the radiator. I spoke with a couple different service advisors at the start of this; one said it was leaking considerably and the other said the tech thought it had a leak and that the leak was in the bottom of the tank. Exhaust was mentioned only because the smoke I saw in the engine compartment was wafting up from the exhaust manifold area, as viewed from above. I imagine it would be "expensive" to find out if the heads are cracked (I imagine it would require taking the engine apart to see) and so I won't find out as long as it keeps running.

[...]

Good point. As I filled the new radiator I squezzed the upper hose to force some of the air out of it. That worked somehwat. I also ran the engine at idle for several minutes (probably like 5-10 minutes) and the hose felt like it had fluid, not air, in it. Additionally I haven't seen high temperatures on the guage while driving the vehicle. Nonetheless I ought to check again under the cap.

Thanks again,

-D

Reply to
Derrick 'dman' Hudson

LOL! :) Looks good, thanks! :)

"It's hard to believe how difficult it is to type stuff when you have nothing to say..." -Gerard

So, now you can finally appreciate all the work I've put in posting on atf.

Alvin in AZ

Reply to
alvinj

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