Valve Lash
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Valve Lash
My 84 Bronco 2 has the 2.8 v6 in it. Recently it has been smoking from the exhaust the smoke has a whitish tint to it. The car does not overheat and doesn’t use antifreeze. I am wondering if the valve lash needing to be adjusting could cause this or if it might be a possible exhaust problem.
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From: Yokosuka, Honshu, Japan
is it a lot of white smoke? if it looks like steam, like what you'd normally see on cold mornings, then it's condensation. if it's a little more than that, you may have a head gasket going or a crack somewhere. check your oil dipstick for milky-like residue and check also in the radiator. If you have nothing in either, it could just be water / condensation in the exhaust which does happen and doesn't mean much of anything that I'm aware of. I used to have that a lot, but after my exhaust upgrade, I haven't noticed quite as much -- then again, it's been in the 90s and 100s here. Could also be blow-by on the intake valves as well -- dumping fuel into cylinders that aren't being fired. Could also be that you have a plug or two or more that isn't firing or isn't firing well enough -- is it running rough at all? I would eliminate all of the "easy stuff" -- check valve lash, check plugs, wires, etc., and if you have the equipment and/or know-how, do a pressure test on the cooling system. that should point you in the right direction.
Last edited by kernel-panic; Aug 3, 2006 at 08:44 PM.
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The dipstick is not milky neither is the radiator. Would it be easier to have condensation in the exhaust if the exhaust needs some work? When my transmission was replaced late last year the exhaust has been leaking from the exhaust manifold where the exhaust pipe bolts up to. I would say the truck runs fairly well and pretty even it even does fairly decent on gas at about 18-20mpg.
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From: Yokosuka, Honshu, Japan
Sounds more like condensation buildup. Also, the catalytic converter's job is to convert carbon monoxide... which part of that process if I'm not mistaken produces water. It's also still possible that the head gasket or somewhere in the top of the cylinder bore is leaking. A pressure test on the cooling system and a compression test on the engine will help determine if that is the case or not. Given the fact that your mpg is as high as it is, though... I'm more likely to suspect condensation buildup and/or water in gas and/or natural catalytic process, especially if you have a stock exhaust with the resonator.
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From: Yes
When does the smoke appear? Is it only when hot, cold, or both? I have leaking valve stem seals, and when my BII idles for an extended period of time, the oil begins to create smoke, the smoke is masked in cooler weather by steam, making it appear white. If it's not taking water, I wouldn't get too worked up about it, but keep in mind that if it's a recent development, unless the temp has dropped in your area, something on the truck is causing it. Just keep an eye on fluid levels (coolant, and engine oil mostly), and out of curiosity, do you have an automatic or manual?
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This may sound weird I dont know but on the nights I park the truck outside is when it smokes the next morning for about the first ten or twenty miles but if its parked in the garge no smoke. The truck uses oil but I am pretty sure its from the vavle covers them self it uses about half a qt every two weeks or so. The transmission is a recently rebuilt c5 three speed auto.
