The Honda K24 engine has long been recognized for its reliability and performance, powering a range of Honda vehicles. However, like any mechanical system, it is not without its flaws. One specific issue that has plagued some Honda K24 engines is related to the timing chain tensioner. In this blog post, we’ll walk you through the Honda K24 timing chain tensioner issue and provide an in-depth explanation of its causes, symptoms, and potential consequences.

The timing chain system plays a crucial role in synchronizing the engine’s internal components, ensuring optimal performance and longevity. At the heart of this system is the timing chain tensioner, which is responsible for maintaining the appropriate tension of the timing chain. When this component malfunctions or fails, it can lead to a series of problems that could affect the engine’s operation.

Understanding the Timing Chain System

The timing chain system in Honda engines, including the K24, is designed to synchronize the rotation of the crankshaft and camshafts. It consists of a metal timing chain that connects the crankshaft to the camshafts, ensuring precise timing of the engine’s valves and pistons. Unlike timing belts, which require periodic replacement, timing chains are generally designed to last for the life of the engine.

The primary function of the timing chain is to maintain the correct timing between the crankshaft and the camshafts. As the crankshaft rotates, it transfers power to the camshafts through the timing chain, which in turn controls the opening and closing of the engine’s valves. Proper timing is essential for optimal engine performance, fuel efficiency, and overall smooth operation.

The timing chain tensioner operates using an internal spring in combination with oil pressure. This is a hydraulic/mechanical tensioner. The way it works is fairly straightforward. The spring engages and applies the necessary tension on the chain until enough oil pressure is achieved. Then, the hydraulic pressure of the oil takes over to maintain tension. This automatic adjustment allows for consistent and optimal timing chain performance under various operating conditions.

Causes of the K24 Timing Chain Tensioner Issue

So why do Honda K24 timing chain tensioners fail? The Honda K24 engine is generally a reliable unit that is known to reach incredibly high mileages on average. However, if there’s one thing these engines are sensitive to, it’s oiling issues. In other words, not following the prescribed oil change intervals, using low quality oil, and letting the engine run on low oil can all affect the longevity of critical engine components. 

Since the timing chain tensioner on these uses oil pressure to maintain tension, any issues with lubrication can cause the tensioner to fail prematurely. Similarly, the timing chain requires consistent, clean oil in order to keep the wear and stretch to a minimum. Old, low quality oil, or not enough oil will lead to premature timing chain stretch, which will ultimately require a major service. 

Common symptoms of a faulty timing chain tensioner

If you suspect that your timing chain tensioner is going bad, here are the most common symptoms to look for. 

• Engine Noise — A noticeable rattling or ticking noise coming from the engine, especially during startup or acceleration, can indicate a problem with the timing chain tensioner.
• Poor Engine Performance — A worn or malfunctioning tensioner can lead to timing chain slack, resulting in decreased engine performance, reduced power, and potentially rough idling.
• Check Engine Light — In some cases, a failing timing chain tensioner can trigger the check engine light to illuminate. This occurs when the engine’s timing becomes noticeably off, affecting the overall performance and emissions. You will commonly see the P0341 code that indicates cam timing issues along with a myriad of other codes.

Consequences of Ignoring the Timing Chain Tensioner Issue

Ignoring a faulty TCT is just about the worst thing you can do to your Honda engine. The timing chain tensioner usually shows first signs of trouble when you start the engine while it’s still hot. The rattle will last for a few seconds and die down soon after. However, as time goes by, you will notice the rattling progressing to a constant noise while idling. Given enough time, the rattle will become apparent at all RPMs. At this time you’re already in dangerous territory. If left unattended, you could potentially experience one of the following catastrophic issues. 

• Valve and Piston Collisions — A failed tensioner can cause the timing chain to skip teeth or lose proper synchronization. This can result in the valves and pistons colliding, leading to bent valves, damaged pistons, or even catastrophic engine failure.
• Timing Chain Breakage — Excessive tension or slack in the timing chain caused by a faulty tensioner can lead to chain breakage. A broken timing chain can cause severe internal engine damage, including valve damage and potential piston-to-valve contact.

Preventing Catastrophic Failure

Regular maintenance and inspection of the timing chain tensioner can help identify potential issues before they escalate into severe engine damage. Timely replacement of the tensioner or related components can prevent catastrophic failure and costly repairs. Stay on top of your oil changes, use quality engine oil, and good filters. 

We at Newparts.com recommend a stricter oil change routine that involves high-quality fully-synthetic oil such as Motul 8100 ECO Light 5W-20 (for older K24 engines), or Motul 8100 ECO Clean 0W-20 (newer K24 engines) in combination with an adequate Mann-Filter, Wix or Genuine Honda oil filter. Change the oil every 4000–5000 miles, and you should keep your timing components healthy for a long time. Not to mention that this type of oil change schedule will keep your VTEC components fresh, all your VTC mechanism functioning properly, and your engine free of sludge. 

Resolving the Timing Chain Tensioner Issue

While older K24 engines haven’t suffered from the timing chain tensioner issue all that much, the newer K24 variants built in 2013 and 2014 weren’t so lucky. Honda has issued a technical service bulletin (TSB) on this matter where they recommend replacing the factory tensioner and installing a small oil filter to catch any debris in engine oil before it reaches the catch valve inside the tensioner itself. 

If your tensioner is showing signs of it needs to be replaced. Here’s how to do it. Keep in mind that the following instruction is for educational purposes only. Consult your Honda shop manual for the specific procedure that applies to your vehicle.  

Step 1 — Lift the Car and Remove the Passenger Side Wheel

Park your vehicle on a flat ground. Locate your main lifting point in the front and use a quality floor jack to get the vehicle in the air. Use a pair of quality jack stands to support the vehicle. Next, remove the passenger side wheel to gain access to the lower part of the engine. Depending on the type of vehicle you’re working on, you may need to remove the plastic wheel well liners or one of their parts to gain access to the chain tensioner cover. 

Step 2 — Remove the Timing Chain Tensioner Cover 

The timing chain tensioner cover is a small cover located to the left of the crank pulley. You can’t miss it. It is held in place by 3 bolts. Remove the bolts to gain access to the tensioner. 

Step 3 — Clean the Sealing Surfaces

With the cover removed, you’ll need to clean the old sealant from both the tensioner cover and the timing chain cover. Honda uses Hondabond 4 from the factory, so you need to clean the residue from the original sealant before you can apply a new bead later on. 

Step 4 — Rotate the Crank Counterclockwise

Next, you’ll need to rotate the crankshaft counterclockwise to put pressure on the tensioner to retract. With the pressure applied, insert a paperclip inside the locking slot on the tensioner to lock it in place. The slot looks like a bicycle chain link. When you rotate the crankshaft enough, the hole in this little link will align with a hole inside the tensioner, allowing you to insert your paperclip. 

Step 5 — Remove the Old Timing Chain Tensioner 

With the tensioner compressed and locked, undo the two bolts that hold it in place. Remove the tensioner and install the new one (get a Genuine Honda part or a quality aftermarket part such as this Cloyes K24 timing chain tensioner). The new tensioner will come with the locking pin already inserted. Once you’ve installed the new tensioner remove the locking pin and let the tensioner click into place. The torque specs for both the tensioner bolts and tensioner door bolts are 12 Nm or 9 lb-ft. 

Get Your K24 Timing Chain Tensioner at Newparts.com 

In conclusion, the timing chain tensioner issue in the Honda K24 engine is a critical concern that owners should be aware of and address promptly. The timing chain system plays a vital role in synchronizing engine components, and a faulty tensioner can lead to severe consequences.

By recognizing the common symptoms of a failing tensioner, such as engine noise, poor performance, and the illumination of the check engine light, you can take proactive measures to address the issue. If you need parts or any supplies for this job, we’re here to help you out! Check out our catalog and find everything you need to fix your Honda K24 engine!