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2011年8月3日星期三

I have a burnt valve in a 1999 ford escort. what's a "quick fix" until i can save to have it repaired?

-It doesn't leak or overheat. The spark plug in the burnt valve doesn't give power. My car stall alot on the take off but once going pass 15MPH, it drives good! There is a faint "ticking" sound though. How long before the engines goes bad? what can i do to keep it going until i can have the heads replaced?Sad news, your engine is already bad. You need a new Cylinder head. A head, new head bolts and gasket set is around 500 dollars on ebay, plus mechanics fees (should be 300-600 depending on mechanics rates) so you are looking at around 1000 for a repair. That would be the safe bet, but some people do what is in the following paragraphs. The problem is, that that costs between 200-500 at a shop, and you still have the old head...I figure better be safe than sorry. Eventually you will loose the cylinder compression completely and the car will run like crap, if at all. It is only a matter of time, there is no real way to tell. It is on borrowed time.







A "burned valve" is a valve that has overheated and lost its ability to hold a leak-free seal. Valve burning is usually limited to exhaust valves because they run much hotter than intake valves.



The diagnosis of a burned valve is usually the result of a compression test. If a cylinder shows little or no compression, it frequently means the exhaust valve is not sealing. The valve may or may not be actually burnt (melted), but have other physical damage such as cracks or areas where pieces of metal are missing or eroded away from the valve face.



The cure for this condition is to remove the cylinder head, replace the bad valve and reface (or replace) the valve seat. As a rule, the head is usually given a complete valve job at the same time because the rest of the valves and guides probably need attention, too. If one exhaust valve has failed, the rest are probably on the verge of failure if they haven't already started to leak.

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