The Biggest Problems Owners Have With The Harley-Davidson Milwaukee-Eight 114 Engine

Harley Davidson has had its share of troublesome engines, such as the problematic twin cam engine. In the case of the Milwaukee-Eight 114, recognized for its power, owners across riding forums together with expert reviews point to a repeating list of problems you may face if you have one. The most common complaints that annoy riders are the oil sumping, oil leaks, overheating, vibrations, lifter failures, and sluggish acceleration. Early production models from 2017 to 2019 seem to be the most troublesomе, but these issues can also be found in newer models. 

When they do appear, reports say it's often sudden, without any obvious indication, including no warning lights. For many riders, the frustration comes from more than the actual breakdown, it's how frequently small issues snowball into bigger, costly repairs, which leaves the owner feeling blindsided when a minor oil leak turns into clutch trouble, or when a simple vibration grows into a balance issue that requires shop time.

Harley developed the Milwaukee-Eight to improve the touring riding experience, but when owners describe the problems they have with the Milwaukee-Eight 114, the technical causes uncover a clear pattern. For example, the oil sumping usually begins with a faulty oil pump that can't scavenge oil correctly, letting it pool in the crankcase. 

This ultimately starves the engine of lubrication, resulting in rough power delivery, even black smoke through the exhaust. If left alone, the mix of oil and air in the system can increase wear on bearings and lifters. On top of that, leaks from weak or worn gaskets can contaminate the clutch assembly, making shifts stiff, noisy, and unpredictable. 

The overheating problem is tied to clogged radiators, leaking seals, and extra friction inside the engine, which is a cycle that builds heat faster than the design can dissipate. Complaints about the bike's excessive vibrations link back to harmonic balancers that either don't work, or have misaligned components that are too much for the engine's counterbalancers to handle at higher speeds. 

Hydraulic lifter failures only compound the list, as they produce valve train noise, risking devastating repair costs. When you consider the myriad of issues, one can only surmise a deeper issue with part quality and, in some cases, early manufacturing flaws.

Despite all of its challenges, going to most Harley-Davidson owners' forums will provide you with the information needed to keep the Milwaukee-Eight 114 running stronger for longer. Taking precautions, such as regular oil level checks, is vital for spotting sumping early, especially if you've had the bike sitting for long periods. 

Conducting a vigilant inspection of gaskets and seals could catch leaks before they damage clutches or make overheating worse. Other steps you can take is to clean the radiator, or radiators, depending on the model, in addition to monitoring fluid levels, and replacing worn tensioners to reduce cooling risks. If you feel that your Milwaukee-Eight 114 vibration is too much, you can try getting a professional alignment check and harmonic balancer replacement. 

Some riders have seen a noticeable difference and much more smoothness. Lifters and valve train noise, on the other hand, are no joke, and a certified service center should address them as soon as possible, in order to catch any pending failures. Lastly, owners of earlier models emphasize the importance of keeping a watchful eye on warranty coverage, since premature wear in pistons, oil pumps, or seals is more common. As with every other Harley engine, being proactive with maintenance and making repairs when required can reduce many of these engine problems so they don't cut into your riding time and bank account.