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Symptoms of a Locked Engine

Is Your Engine Locked UpInitially, it might seem like your engine is seized. When your try to start your car, your engine won’t turn at all. However, that’s just one cause of a locked engine. It’s one of the most common and perhaps the most expensive to repair, but there are other conditions it may also be.

On the day when you least expect it, you start the car and suddenly hear an unusually loud clunking noise. Your car shut off and won’t start, The tank is full and the battery is relatively new. Odds are the engine seized! What do you do now? You can always sell your car with CarBrain, or find out more about locked engines below.

So what happens if your engine locks up? How to know if your engine is locked up? Can a seized motor be fixed? More importantly, how to unlock a seized engine? When your engine locks up while driving all these questions will be running through your mind. In this article we'll try and outline the signs of a locked engine, and engine lock up causes and fixes.

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Did You Know?

A seized engine in need of repair could easily cost you $3,000 or more to fix! This makes your car a tough pitch to sell. Fortunately, CarBrain specializes in buying cars that are in less than perfect condition! We’ll buy your vehicle whether the rods are knocking or if engine seizure has happened. With tow partners all across the US. We’re prepared to deliver payment and tow your car for FREE! In just 1 to 2 business days.

Before throwing your hard earned cash into the bottomless pit of engine repairs, Check your vehicles value to see if the repairs are worth it.

Is it worth fixing a seized engine?

The first step is to determine whether the issues are severe or not. If they are simple and have a quick  seized engine fix then, by all means, go ahead and get that car fixed. Now, when a vehicle has a seized or blown engine the cost of repair could potentially exceeds the vehicle's value. To avoid overspending on repairs it's important to make the right decision and sell the vehicle AS-IS for the best offer possible.

What is a Seized Engine?

What is a Seized Engine?An engine seizes up due to mechanical failure, usually associated with oil starvation. When an engine runs out of oil or the oil isn’t circulating as it should, internal metal parts rub against each other, creating enormous amounts of heat from the friction. Bearings that are meant to allow for smooth movement grind against the crankshaft and camshaft, sometimes literally welding themselves onto other parts. As a result, if your engine locked up while driving, your engine will suddenly sound really rough, then stop on its own. Seized engines due to lack of oil can range from a little engine damage to major damage.

An engine can seize from not running too. In that case, it’s a little different. The piston rings ‘freeze’ against the cylinder walls from rusting. This is most commonly seen on old cars that are due for restoration.

Hydrolocked Engine

Hydrolocked EngineAn engine hydrolock occurs when water gets into the engine’s combustion chamber. On the combustion stroke, the piston is unable to reach the top of its stroke because the water won’t compress like the air-fuel mixture would. The engine suddenly stops. If the engine is at low RPMs, you may escape without critical engine damage. At higher RPMs, bent connecting rods and busted pistons are almost guaranteed.

Vapor Locked Engine

This one’s a little different. Vapor lock doesn’t mean your engine doesn’t turn over, but your engine won’t start. Vapor lock is a fuel system problem, usually found on older cars with low-pressure fuel systems. When gasoline in the fuel lines or fuel pump turns from liquid to gas, it starves the engine of fuel and it stops running. When a vapor lock occurs, your engine will begin to sputter and lose power, the turn off. It won’t start though, no matter how hard to try initially.

Should I fix my car or Sell it As Is?

Should I fix my car or Sell it As Is?

What Causes a Locked Engine?

What Causes a Locked Engine?For a bad starter or seized engine, common causes include infrequent oil changes and running the engine out of oil. It could also be a broken engine oil pump or a sudden failure inside the engine.

For a hydrolocked engine, you’ll know its cause when it happens. It’s due to water getting into the engine through the air intake, probably from driving through a deep puddle or floodwaters.

For an engine vapor lock, it’s almost always related to extreme heat. What happens is the fuel in the lines between the fuel pump and the engine turn to fuel vapor. It can be from sitting in traffic in sweltering heat or from turning off your engine when it’s hot out, and the fuel temperature quickly rises. The fuel pump can’t move fuel vapor and the pump cavitates. Now, can you "unseize an engine"?

What to Do When Your Engine Locks Up

If your engine locks up when you’re on the road, put your transmission in neutral and coast to the side of the road. If it happens when your already parked, you’re not going anywhere anyway. Try turning your engine over once or twice but if it doesn’t crank, don’t keep trying. You could burn out your starter or cause more problems as well. 

How to Free a Locked Up Motor

Treating a locked up motor depends on its cause. You can tell if your engine is locked by trying to turn the crankshaft with a breaker bar. If it turns, the engine isn’t seized, and you should look for a different cause.

  • If your engine has seized up while you’re driving, there’s nothing you can do about it short of an intensive engine repair or replacement.

  • If you have an engine that seized from sitting for a long time, pull the spark plugs out of all the cylinders. Fill the cylinders with engine oil and let it sit for a few days. Then, try turning the engine over with a breaker bar. If it moves, you may be able to salvage the engine. If not, you’ll have to pull it apart and rebuild it.

  • If your engine is hydrolocked, take out the spark plugs right away and crank the engine over. The water will pump out of the cylinders, releasing the hydrolock. That’s IF there aren’t damaged parts inside.

  • For a vapor locked engine, you need the fuel to cool to the point of condensing. It can happen frequently just by letting it sit and cool off. Or, if you need to get it going right away, you can cool off the fuel pump and lines by splashing cold water or ice on them, condensing the vapor back to liquid.

My Engine Locked Up - Repair Cost Averages?

My Engine Locked Up - Repair Cost Average?A vapor locked engine is usually no cost to repair if you’re able to just cool off the system quickly. If the fuel pump has overheated, you can expect it to cost $500 to $1500 for a replacement.

An engine hydrolock could be as little as the cost of new spark plugs and an oil change. Or, if the engine was damaged when the hydrolock happened, you may need to replace the engine at a cost of thousands of dollars.

If you want to know more about engine damage, we created a guide on blown engines on various makes and models of cars throughout the years you can check out.

Can a Seized Engine be Rebuilt?

If an engine is seized due to oil starvation, you might be able to rebuild the seized engine, but the labor costs can reach epic heights. A mechanic will have to inspect your engine to make sure no major irreparable damage was done, and particularly that a rod hasn't gone through the engine block. Another thing to look out for is the overheating of an engine after it seized. The heat can warp parts of the engine you won't be able to see, so it might be more costly than initially expected. It's probably better to explore options of selling your car with a blown engine.

Seized Engine Fix Costs

If the engine has seized and needs a rebuild or replacement, it could easily become $3,000 or more for your repair.

If you can’t afford the expense and downtime a locked up motor comes with, let us get you out of it. At CarBrain, we will make a guaranteed offer for your car in as-is condition. If you accept our offer, we’ll come pick up your car as it sits and put money in your pocket on the spot.

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