Anmacc2 wrote:
My van is burning oil because of rings. It is slowly getting worse. I am now burning 1qt per two tanks of gas. It is too big a job and too expensive and not worth it to me to fix it at this point. What will happen as the issue progresses? Will I just burn more and more oil? I only put maybe 9,000 miles a year on it.
Please stay to the topic and answer the specific question to help me. :)
I sincerely appreciate the generosity and caring of this site!!!
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It only smokes when I first start it. After just a minute or two it stops. No residue on the fender or exhaust. Does that she'd more light?
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I have one plug that fouls. Drivers side, third one back. I change it every 10-15 thousand miles when I develop a miss. Check engine light comes on occasionally. I put injector cleaner in the gas and run it down the hwy at 75mph for a hundred miles and it goes off at some point. Planning a 6000 mile road trip in the spring and hoping to nurse it through a couple more years.
As other have indicated, the most likely scenario for smoking upon start-up is worn stems & valve seals, usually accompanied by plugging of cylinder-head oil drain-back ports by sludge. The cold, thick rocker-arm oil builds up inside the valve covers until it pools and immerses the valve guides. The large vacuum present around the intake valve guides suck the oil directly into the intake until this rocker oil becomes warm enough to drain away quicker. Merely removing the valve covers and insuring the drain-back holes are not plugged may help with start-up oil issues.
The most likely scenario for an exceptionally fouled plug is a broken ring or unretained wrist pin which grooves the cylinder wall. Usually when the valve stems are worn, all the rings might be too. All this is exasperated by any past hard service and/or too long of oil service intervals.
The worn valve guides cause some oil-based carbon build-up in the cylinder head chambers which are also likely to cause some hard pinging or detonation under load because of raised compression ratios. This can cause broken piston lands/rings and is in fact the primary cause of such. This is a problem when such an engine is used for hard work such as towing.
FYI, one other enemy of occasional tow vehicles is extended non-use. Both dry valve stem surfaces and dry, shiny cylinder walls can develop rust and sticking from long periods of disuse. The rusted stems then damage both the seals and guides and the rusty cylinders tend to cause the rings to clog and jam from scraped rust debris. Ideally, engines that are not driven often would be stored by properly moth-balling the engines by at least coating the cylinder walls with an oily preservative upon last shut-down. Valves, buried beneath covers are not so easy to coat. After quite a number of years for instance, rusted valves can stick so bad the spring pressure may not reseat them without help.
Buying a used engine can be a chancy affair since the used engine may be in similar worn shape and a
set major expense is the labor to swap them out. A new, or rebuilt long block only costs marginally more and labor is the same, but a more reliable fix. One then ends up with a used truck at less than used truck price, but with a new engine. This also makes a good argument against merely buying another similar used truck. Ideally one would drive most of their investment money back out in the long term and if not, resale has a slight advantage. It is also easier to justify installing a new transmission, or other drivetrain, should the need arise. And these repairs are
still significantly less than a new truck.
Lastly, you can run for several years just by adding oil at the low mileage accumulation you have suggested. There is of course a lower reliability factor depending on just how bad the hidden wear has progressed. Remember, the timing chain, lifters, cam and bearings are probably not so great either, and such a worn engine is likely to have some oil leaks periodically cropping up, particularily from excess crankcase pressure caused by blow-by.
Wes
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