Diesel Truck Repair: 3 Common Causes Of High Crank Time

Knowing how to diagnose your diesel truck when it starts to malfunction can be the key to avoiding expensive and tedious repairs. Even if you can't diagnose the problem, you should at least know about the types of problems you should be wary of. Diesel trucks operating under a common-rail injection system usually have a crank time between 3 to 5 seconds. If you've noticed that the crank time of your diesel truck has become longer, you'll want to take it to a diesel truck repair shop immediately. Here are 3 common causes.

Loose Connecting Tubes

The engine relies on diesel and other types of fluid to function properly. If insufficient fluids are being delivered to the engine, you can expect the crank time to lengthen; thus, loose connecting tubes are one of the most common causes of higher crank times. To determine if this is the actual cause, you can try tightening all of the connecting tubes.

Leaking Relief Valve

High crank times can be due to leaking relief valves. The leak means that the fluids are being pushed backwards into the system instead of doing their job. Looking for a leaking relief valve can be difficult, especially since some relief valves are cleverly hidden. You'll basically want to look for remnants of diesel fuel at the joints where the valves connect.

Defective or Malfunctioning Injector

Most diesel trucks have quite a lot of injectors and figuring out which injector is malfunctioning or defective can take a long time. You can start off by removing the valve cover and cranking the engine before letting it sit idle. Basically, you're looking for small wisps of smoke coming from the injectors and the smell of diesel fuel. These indicate that there are external cracks present in one or more injector. At which point, you'll want to start pinpointing which cylinder may be causing the problem.

Determining what the main culprit of a high crank time is can be difficult for those who are inexperienced. If you can't figure out what the cause of the problem is or how you can solve it, take your diesel truck to a repair shop immediately before hitting the road again. Solve the problem as soon as possible to avoid wasting more fuel and energy. You'll also want to repair your diesel truck before the problem worsens and becomes an even bigger headache to deal with.