We really like the ride of the Polaris UTVs. Unfortunately, we have noticed that Polaris built the RZR, RZR-S, and Ranger XP with an unreliable fuel pump. In fact, the fuel pump is one of the main problems we see at our service and performance shop. The symptoms you typically experience when your pump is failing are poor upper RPM performance, a loss of top speed and poor acceleration. This definitely makes your Polaris much less fun to drive, but even more importantly, a fuel pump problem can cause your engine devastating damage by not supplying enough fuel. When your engine doesn't receive the required fuel it will run lean.
This creates heat which can cause detonation in the combustion chamber. The worst case scenario (and we have seen this many times) is that the intense heat will actually melt a hole in your piston. Here is what happens. After some usage the pump will wear and then drop from the factory PSI setting of 39 psi, to the low 30s. When your upper revs are sluggish you just aren't getting any fuel. To test this install a fuel pressure gauge at your tank outlet. You can buy these at NAPA or PEP Boys. It is necessary that you rev your engine when testing because many times the pressure will be good at idle but not at the upper RPMs.
To replace your pump with the OEM fuel pump you will need to spend upwards of $600. The high price is because it is only available with the complete fuel tank assembly. Fortunately you can purchase a replacement fuel pump which will work on most Polaris S X S vehicles. Replacement pumps come with color instructions and include everything you will need for installation. Generally they can be installed in about 30 minutes with simple hand tools. The pump plugs right in with no wiring needed.
[caption id="attachment_818" align="alignright" width="140" caption="Replacement pump from Alba Racing"][/caption]
If you are experiencing poor performance with your Polaris Ranger or RZR this may be your problem. Check out your fuel PSI and if needed get a replacement fuel pump. You bought your Polaris to have some great times. Now you can get back on your UTV and enjoy its top performance once again. As a sidenote this same problematic fuel pump is used in many of the fuel injected Polaris quads. If you own a Polaris ATV and you are having similar symptoms simply follow the same procedure for testing the PSI. Replacement pumps are also available for the Polaris Sportsman.
Patrick Hove manages Alba Racing, a service and performance center for motorcycles, ATVs and UTVs in Santee, California. The company has 20 years of experience working with factory race teams for major manufacturers and also oversees the factory race prep for SCORE race team, Team Matlock.
If you're interested in increasing your performance and the riding experience (improve stability or handling) you can reach company at 858-413-2598 Pacific Time or view the website at http://teamalbaracing.com.
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