Diesel Fuel Injector Balance Pressure Tester - Yes, You Can Do It Yourself!

This tester is required for proper IDI (indirect injection) diesel fuel injector testing and overhaul. It will work on any mechanical Bosch-type fuel injector with an adjustable pressure release function - although you may have to come up with your own adapter to attach the injector to the pop tester. (manufactured up to the mid-1990s). The metric thread size on this tester to connect to the top of the fuel injector is M12 x 1,5.  Assembled with special FLUTTER GUARD pressure gauge to stabilize needle bounce. This will allow for more accurate pressure release readings during testing.

If you don't think tuning and balancing your injectors is important to think again. Dirty or worn injectors can cause poor spray patterns leading to loss of power, poor fuel economy, and excess exhaust smoke. Unbalanced injectors (meaning release pressures are not set within 50 psi of each other) can lead to rough idle, poor acceleration, and excessive injector knock. Worn-out injector tips can lead to all of the above plus lots of $$ going out your exhaust pipe. With diesel fuel at $3.00+ a gallon, you could pay for this tester in a couple of months!

IMPORTANT NOTE: Contrary to popular belief this is an important service procedure you can do at home. You will actually be surprised at how simple it is with the right tools. Even though it is not difficult, it can be time-consuming to get the pressures of all your injectors balanced just right and that is one of the reasons diesel shops charge so much money to do it. Here is a quick summary of the procedure:

The testing procedure is quite simple:

• Bolt the tester to your workbench
• Prepare the fluid containment bottle and diffuser as explain in the free video instructions
• Fill the bottle with our recommended mix of diesel fuel and transmission fluid
• Attach a fuel injector to the hard line fitting included
• Bleed the air out at the injector fitting into the fluid bottle
• Attach 9 to 10 foot hose to bottle and route outside ( to exhaust fumes )
• Pump the handle a few times up to the point the injector fires (pops)
• Note the consistency of the spray pattern
• Read the release pressure in PSI
• Hold pressure with handle just before release point and check for injector leaks
• Disassemble the injector to inspect / clean (search injector cleaning kit)
• Select thicker or thinner shim washer to change pressure (search shim washer)
• Measure shims with dial caliper to confirm correct size (search dial caliper)
• Clean, oil, and reassemble injector to proper torque (search torque wrench)
• Repeat test and re-adjust pressure if needed
• Replace with new nozzles if yours fail the test (search injector nozzles on this site)
• Install back into your engine using new crush washers and injector return hose (search injector service kits)

ADDED BONUS: As an added bonus Kent Bergsma's complete PDF DIGITAL DOWNLOAD manual to cleaning, testing and adjusting fuel injectors will be included at no additional cost. This guide will walk you through the procedures step-by-step in plain English. It will be uploaded to your Mercedessource account automatically upon purchase of the tester. 

SPECIAL INJECTOR SERVICE TOOL KITS AVAILABLE: If you don't have the tools handy to work on your injectors we have put together a couple affordable tool kits. Basic requirements include the proper injector socket, a torque wrench, and a dial caliper to measure the shim washer thickness (all listed below).You will be hard-pressed to find better quality for the price we offer. Our markup on these tools is set very low just to help you get started working on your own fuel injectors. 

ALSO NEEDED: If you are going to properly change your injector pressure release settings you will also need a variety of shims. We carry shim kits on this site as well. 

If you own an older gasoline Mercedes you can use this basic tester to test your CIS fuel Injectors. BUT ...... you will need a conversion kit with a smaller gauge. See products below for the Diesel to Gasoline Tester Conversion kit

SAFETY RECOMMENDATION: For your own health always use a quality organic vapor / paint respirator with current filters when using this tester in an enclosed space. Even with the exhaust hose you really don't want to be breathing diesel fuel for long periods of time without ventilation and protection.