"Prelubing" --a system that uses electric pumps or hydraulic accumulators to pressurize your engine's oiling system before you start up the engine--has been getting more and more attention. The theory has been that a preluber system reduces wear on engine components by starting the lubrication process before the engine turns over.

Most of the companies make rather vague or incomplete references to studies made some indefinite time ago. Such allusions don't really help answer the question we're often asked by our readers: "Do these preluber things really reduce engine wear?"

In our December '87 issue, we featured an article about the Pre-Luber and PreTurboLuber from Lubrication Research. We installed one of their PreTurboLubers on our turbo-charged "Project: GTI.'' Admittedly, our main goal was not reduced engine wear but rather improved turbocharger life. The PreTurboLuber has a second function of running oil through the turbocharger after the engine is turned off. This cools off the the turbo bearings and reduces "coking" or carbonizing of the engine oil, as well as increasing bearing life.

We sold "Project: GTI'' two years ago, but the PreTurboLuber was still going strong, as was the turbocharger. After some problems with turbocharger life we had had in the past, this was a positive step--the oil running through the turbo probably helped bearing life. It looked, from this example, that the preluber helped turbocharger bearing life, but the question still remained: "Does a preluber help engine life?"

After years of accepting at face value the preluber concept, we finally received word regarding a preluber company that took the initiative to actually have tests performed. And the results are interesting. As we had been very impressed with the quality of Lubrication Research's Pre-Luber, we weren't surprised to see that is was that firm that had gone to the trouble to have those tests run.

The test series was conducted by an independent engineering company, RC Engineering and Management Services, Inc. of Grand Blanc, Michigan. The actual tests were performed at Vehicle Research and Development, Inc. of Almont, Michigan, a company used by the "Big Three" auto manufacturers and their suppliers. Two, identical Chevrolet 5.7-liter V8s were prepared and tested over a period of ten days in a 0° F environment.

Each motor was started for 650 coldstart cycles during the ten-day test period. Before the test began, each rod and main bearing was carefully weighed and the weight recorded. At the end of the test, each bearing's weight was again checked and recorded. The difference in weight was the amount the bearing had worn. By using this method, even small amounts of bearing wear could be accurately measured.

Admittedly, 650 starts is only equal to about three months of driving-not a long time. That's what makes the test results so interesting. In spite of the shortness of the tests, there were very real and measurable bearing wear differences. Main bearing wear on the Pre-Luber-equipped engine was reduced by an average of 11 percent, with a range from 8-16 percent. Connecting rod bearing wear was reduced an average of 37 percent, with a range of 11-53 percent. Finally, a visual inspection of the cylinder bores show less scuffing of the cylinder walls in the Pre-Luber engine. These numbers and the inspection results seem to be a strong indication that the preluber may help in the reduction of the engine wear

Readers with an extremely sharp memory or a well-stocked collection of VW & Porsche magazines will recall that the Pre-Luber featured a number of custom engineered, designed and manufactured parts to achieve reliability and quick priming abilities. That hasn't changed--the quality of Lubrication Research's product is excellent. When you turn the key and switch on the ignition before starting your engine, you need to pause briefly When you pause, the timer circuitry of the PreLuber switches on the pump and pressurizes your engine's oiling system. If you've got an oil pressure gauge, you'll see the needle swing right up.

It looks as though a Pre-Luber could more than pay for itself if you have a car with an expensive or high-performance engine. We think we would seriously consider it. And we'd like to thank Lubrication Research for providing some real world test information about an interesting product.

VW&PORSCHE, August 1990