Ford 3.5/3.7 Cyclone Water Pump Failure – Symptoms & Solutions

Water pump failure is one of the most common big-expense problems that occurs on transversely mounted Cyclone engines, especially the 3.5L and 3.7L V6s. Due to packaging limitations, the water pump on those engines forced Ford to mount the water pump internally, making it especially difficult to reach and repair. When these internal water pumps do fail, the repair is very expensive and time-consuming. Not to mention, if the water pump is left in disrepair for too long, it can allow coolant to seep into the engine oil, potentially causing complete engine failure. 

In this guide, we’ll cover the infamous 3.5/3.7 Cyclone water pump failure issue in detail, going over what causes it, common symptoms associated with it, and how to go about repairing and preventing the issue.

If you are interested in learning more about other common 3.5/3.7 Cyclone engine issues, take a look at our 3 Most Common 3.7 Cyclone V6 Engine Problems Guide.

Ford 3.5/3.7 Cyclone Water Pump Location

One of the biggest factors in the Cyclone/Duratec water pump failure problem is where Ford decided to mount the water pump on transversely mounted variants of the 3.5 and 3.7 Duratec. All front-wheel drive and all-wheel drive models that used either engine were affected by the problem. 

Since the drivetrain for both FWD and AWD cars requires a transversely mounted engine, Ford had to figure out how to make the Cyclone fit under the hood without fundamentally changing the design of the engine. As a result, they moved the externally mounted water pump (used on longitudinally mounted engines) to the valley behind the timing cover to clear up more space.

As a result of Ford moving the water pump to the interior of the engine, it is also driven by the timing chain. The drive mechanism for the water pump causes issues of its own, which we’ll get to in a second. Aside from being annoying to get to, the internally mounted pump can also have serious consequences for the rest of the engine if coolant is allowed to leak into the crankcase. It also makes detecting a water pump failure extremely difficult, as you can’t visually see coolant leaking from the pump.

What Is the Problem?

The 3.5/3.7 Duratec’s water pump failure issue revolves around both the pump’s location and the way that it is driven. With the water pump mounted in the valley behind the timing cover, it is in a perfect position to be driven by the timing chain, which is known to have stretching issues on other Ford V6 engines like the 3.5L EcoBoost that shares a very similar design with the Cyclone. The pump is driven by a sprocket surrounding a bearing that is spun by the main chain itself.

Over time, and as the timing chain continues to gather slack, the vibrations from the loose chain cause the pump bearings to wear out which allows the timing center to move around. Once there is play in the pump bearing, the entire assembly moves around, allowing coolant to leak past the bearing seal. At that point, the water pump gaskets are the only thing keeping the coolant in and if they develop cracks or degrade, coolant is allowed to leak directly into the crankcase, mixing with the engine oil.

This is where the real problems begin. Coolant mixing with engine oil is not good. It can cause corrosion and lots of internal wear as the Ford 3.7 Cyclone oil is no longer able to properly lubricate moving parts. Basically, it can cause a lot of internal engine damage and can even lead to the engine seizing completely. 

3.5/3.7 Cyclone Water Pump Failure Symptoms

• Rattling/clunking from engine
• Milky oil
• Visible leak
• Overheating
• Slop in the water pump assembly (once the timing cover is off)

The real issue is when the bearings go and the timing center begins moving around. This will typically cause an audible rattling or knocking sound from the front engine cover area. Coolant mixing with the oil will cause the oil to look like a chocolate milky mess. 

Ford actually did build in somewhat of a failsafe into the water pump design, which features a weep hole that drains externally, below the alternator. So, despite being internally mounted, a visible coolant leak below the alternator indicates that coolant has breached the first gasket and that the water pump is failing. Once the front timing cover is off of the engine, you can check to see if there is any play in the water pump assembly by moving it with your hand. If there is play, the water pump shaft is likely faulty, meaning that the water pump needs to be replaced. 

Finally, the 3.7L Cyclone may begin overheating if too much coolant is lost. Check out this video which goes in-depth about failing 3.7 V6 water pumps and what to look out for:

Can You Prevent Ford Duratec Water Pump Failure?

Unfortunately, the 3.5/3.7 Duratec’s water pump failure issue is caused by the inherent design of the pump itself. For that reason, there isn’t much that you can do to prevent the issue from happening. With that being said, preemptively replacing the water pump can spare you thousands of dollars in other repair costs associated with water pump failure. For instance, if a failed water pump isn’t repaired promptly, it can lead to scoring on the camshafts, other polished surfaces, and even complete engine failure which can cost tens of thousands of dollars to replace. For that reason, replacing your Cyclone V6s water pump every 150,000 miles or so is a great idea to limit the damage.

While there isn’t a ton of conclusive evidence to support this claim, some 3.5/3.7 Duratec owners claim that using thicker engine oil can help reduce the risk of water pump failure. Since timing chain stretch can exacerbate water pump failure by wearing out the pump bearing earlier, reducing timing chain stretch can help prolong water pump life. Using thicker oils can help lubricate the chain better than thinner oils, which lessens stretch. Once again, this is just speculation, but the overall argument makes sense. 

Ultimately, though, most certified Ford mechanics agree that there isn’t much that can be done to prevent premature Cyclone water pump failure.

Water Pump Failure Fixes and Repair Costs

Average Cost to Repair a 3.5/3.7 Duratec Water Pump: $1,200-$2,200

What makes this issue so annoying is the fact that there is no easy, cheap, or quick fix to solve it. Since the Cyclone’s water pump is located on the interior of the engine, it is extremely difficult to reach for mechanics and home DIY-ers alike. Since the front timing cover and all of the timing components need to be removed to replace the water pump, mechanics typically charge for around 12 to 14 hours to complete a water pump replacement on the 3.5/3.7 Cyclone. That typically comes out to around $1,200-$2,000 in labor costs alone. Luckily, the water pump itself only costs around $50.

Since a water pump replacement on the 3.5/3.7 Duratec is such an involved job that requires removing all of the timing components, it is also a good time to check the health of all of those components. While the timing cover is off, it is a good idea to check if the timing chain has gathered enough slack to warrant being replaced, in addition to the timing chain tensioners, guides, and crank seal. Replacing those items at the same time will save a ton of money on labor if they need to be replaced anyway. 

While at this point, Ford has not offered any customer financial assistance for the issue which is a clear design flaw on the Cyclone V6, a new class action lawsuit was filed in 2022 to potentially get Ford to cover water pump repairs. At this point, the results of the lawsuit are pending. You can read more about it here.