Westly's 1.9 liter normally aspirated (non-turbo) diesel was installed in 1992, but I don't know if the engine was new, used or overhauled at the time. Nor do I know exactly how many miles have been driven since the installation as the odometer was inoperable much of the time. By analyzing maintenance receipts and taking into consideration information from the Previous Owner, I figure in the neighborhood of 30,000 miles is close. I've not performed a compression test, but the engine seems tight, feels strong, runs as smooth as a diesel can be expected to, has good oil pressure and doesn't leak or burn oil - I never have to add any extra between oil changes.
I had previously switched to synthetic motor oil after observing high oil temperatures at freeway speeds as synthetic oil will sustain higher operating temperatures than dino oil without breaking down. Now 5,000 miles had passed since the move to Mobil 1 5W40 synthetic "Protection For Hard-Working Diesel Trucks" oil and I was curious about how it was holding up.
Knowing that an oil analysis would provide useful information about the condition of the oil and engine, I requested a test kit from Blackstone Laboratories.
The test kit consists of a small (3.5 oz) plastic bottle, a larger bottle, a zip-lock bag and some absorbent materiel. You fill the small bottle with a sample of oil (they recommend if you are changing your oil at the time, try to take it from the middle of the dump rather than the first or last oil out). Complete a form with information about the engine, mileage, miles the oil was used, how much oil was added between changes and so on and put it in the larger bottle along with the sample (which is in the zip-lock bag with the absorbent materiel). Seal it tightly! The postage to mail it to Fort Wayne, Indiana was $2.29. The cost of the analysis was $25, plus $10 more for a "TBN" which measures the additives available (useful if you want to extend mileage between oil changes). If you have a fleet of vehicles, you can prepay for multiples of samples which reduces the per sample cost.
|Sample Test Kit - free from Blackstone|
I collected the sample, mailed it off and in about a week I received an e-mail with an attached .pdf of the report. They also mailed a hard copy along with a sheet explaining how to interpret the report, and a couple more test kits.
The first report came back identifying my van as an air-cooled gas engine; likely the default for a 1982 Vanagon. I contacted Blackstone and we got it straightened out. A new report came soon after. They keep track of each vehicle and report and the previous values will show on a later report for comparison.
|The report - click to enlarge|
The report and accompanying comments indicate Westly's engine is in very good condition, showing wear that's typical for the mileage of the oil sample, and a "strong TBN" suggesting that the oil change interval could be stretched out to 7,000 miles. I might go with 6,000 miles, which would bring the cost of my synthetic oil change down to what I would spend on a dino change every 3,000 miles. Of course, Blackstone Labs emphatically states that how often you change your oil is up to you, and assumes no responsibility beyond the cost of the analysis in the event of any oil related engine troubles.
As the cost of the analysis is just a little less than the cost of a do-it-yourself synthetic oil change, I don't foresee ordering one with every oil change, but possibly once a year.
Since I posted this, I've been informed by some Vanagon drivers that oil analysis reports are a waste of time. The reason, they say, is that your engine is going to wear out anyway. Why spend money on a report that confirms it? If you have a cracked block or leaking head gasket, there are other more expedient ways of finding out (water/oil mixed, exhaust gasses in cooling system, etc.). Are you going to tear down your engine just because a report showed an increase in the elemental components of bearing surfaces? It's just one more thing to worry about!
Valid points, but here's why I would still consider it an important part of regular maintenance. I wasn't concerned about Westly's oil temperature until after installing an oil temp gauge. Once I was aware of the problem, I could do something about it. This first report is my benchmark. Maybe, depending on annual mileage, I'll wait two years to do the next report, but when I do I'll have a comparison. If a future report shows some anomaly, I'll try to discover why - maybe an engine tear down would be in order but maybe not. If all the report shows is the natural progression of wear and tear, then some prediction might be made as to the expected service life of the engine. Without the report's information about additives present in the oil (what they refer to as TBN), I could be changing oil unnecessarily early - a waste of time, money and resources.