My 1990 HOnda just started blowing white smoke. It's not running hot, but I'm worried?

Question

It is coming from my exhaust and this morning it is only blowing a little bit, but still there. Will it catch on fire if I continue to drive it?

Answer 1

If the whiff you catch has a sort of sickening sweet smell it is most likely coolant, and the most likely source is a blown head gasket. Against the possibility that you may not be entirely familiar with car mechanicals, let me explain.

Your engine has two major parts--a cylinder head and a block. The cylinder head, as the word head suggests, sits on top (unless your engine has a horizontally opposed design like the old beetles, subarus and a number of the porshes, but we need not go into that). In any event, the cylinder head contains the valves and the assemblies that operate them. The block contains the pistons, crankshaft, etc.).

Where they are joined, there is a gasket that provides a seal between the two components and it is called the head gasket. It is designed with a number of holes in it to allow oil and coolant to pass between the head and the block in separate journals or tubes. When something happens to the gasket, either a piece of it is blown out due to age or pressure, or a gap develops between the two machined surfaces of the head and block that allows the coolant and/or the oil to escape from their separate passages, it is said that the gasket is "blown." In fact that is something of a misnomer, as really the gasket is only blown if in fact a piece of it has physically been "blown" out. Often as not, what has really happened is that the head or sometimes even the block has become slightly warped, or one or more of the head bolts that hold the two together is improperly tightened (torqued) and has allowed a gap to develop, while the head gasket itself is still relatively in tact. Still, the gap is allowing the fluids to escape their intended paths. Left long enough in this condition, the unsupported gasket willbe subjected to pressures from the escaping fluids and the combustion chambers that may also be leaking into the gaps to actually damage the gasket, but often if it is caught early this can be minimized.

Now, as to what do do.

First, pull your oil dipstick and see if there is any unusual sludge, foam, muddy brown ****, or actual antifreeze on it. This is one means of determining if you have a blown head gasket, as it will signal that there is coolant in the oil.

Second, with the engine cold, open the radiator cap and look for evidence of muddy brown sludge or even oil floating on top of the coolant. Again, this would be evidence of a blown head gasket.

In either case, it is still not quite time to panic.

If the car is quite old and has very high mileage, you will have to decide just how much effort and money you want to put into trying to salvage it, but I do not regard a 90 Honda as being something one just throws away without a thought. Yes it is 16 years old, but it may still have some considerable life left in it with a little TLC.

One thing you can try is to pull the valve cover and on top of the head you will see perhaps eight to ten head bolts. These are the bolts that pass through the cylinder head and into the block securing the one to the other. If the gasket is still in tact, and you have no real way of determining that, but you can take a chance without any real risk--you can try retorqueing these bolts using a torque wrench which measures the force you are applying to each bolt (it is important that they all be torqued evenly). Should you care to try this, and desire more instruction, please feel free to contact me at [e-mail].

The purpose of this exercise would be to try to close the gaps and press the gasket back into a sealing position. If does not always work, and sometimes it does not work completely, but can greatly reduce the leakage between the journals, or to the combustion chambers, and the car can continue to be driven without having to go to the expense or trouble of pulling the head and replacing the gasket.

A few years ago I bought a 91 mercedes with a significant head gasket leak for a pretty fair discount below its typical selling price owning to the mechnical problem it had. Rather than pull the head right away, I retorqued the head bolts a few pounds past spec, and nursed the car along for about three years until my son decided one evening to see how fast it could go--not a good thing to do with a weak head gasket. Well, somewhere around 110 mph he succeeded in blowing the gasket and I then I have to pull the head and make repairs, but the point is that I managed to get three years out of the car with a known problem by taking steps to minimize the problem. You may very well be able to do the same.

If you would like to talk about this at greater length, please feel free to contact me at the aforementioned address.

Answer 2

You should be worried, cause you've got a leak between your coolant and the engine. Most likely a blown head, but could be worse. If your not getting it fixed right away, you need to keep an eye on both your coolant levels and the engine oil. You also probably need to change your oil more often then normal if you want to milk this out for a while before getting it fixed. The extra water in the oil will reduce the effectiveness of the oil.

Answer 3

It sounds like a blown head gasket. Water is entering the piston bores. It will start overheating when the water starts running low. I wouldn't repair it. A 1990 Honda just isn't worth fixing. If you have had this car since new then it certainly doesn't owe you anything.

Answer 4

Well it can be a million things. Where is the smoke coming from? Have you checked the oil? Your oil could be very low and burning. If you're not overheating.. it might be a possiblity if the anti-freeze is low, and also burning... and you may overheat soon. I would check to see if you're leaking anything. If it has anything to do with the cooling system.. it should be cheap and easy to fix, unless its the radiator, then you're spending some money. It may just be a radiator or heater hose? If you have no power steering, that could be low too.. just check to see if it's leaking, try to find where the smoke is coming from, and check your oil,transmission,power steering, and coolant. Good luck!

Answer 5

Check the oil and its pipes!! White smoke and the exhuast could mean oil is leaking in the wrong places inside the engine block...

Answer 6

from the hood or is it exhaust from the back? how often do you get this?

probably need to check rubber gaskets if hood, and piston rings if exhaust. Might need to overhaul the engine. But check with mechanic to be sure.

Answer 7

if you are blowing white smoke out of your exhaust, then you will need a new head gasket. it can be expensive, anywhere from $300-$700 usd.

Answer 8

time to start worrying...probably big bucks. head gasket blown, leaking antifreeze into cylinders causing white smoke from tail pipe. check coolant level, if low, a-oh...