The following article is reprinted from the Spring 2001 edition of the Society of Accredited Marine Surveyors newsletter, with permission of the authors.
The companion article to these notes (on page 12) was written by one of our SAMS® Affiliate Members, Floyd Friloux of Lubri-Port Laboratories, Kenner, LA.
Floyd has a great deal of experience in this field and graciously consented to preparing the article after being harassed for a couple of years to get some basic procedures on paper.
As with all things in the surveying profession no two circumstances are exactly the same, there are always other factors that affect what is needed or practical in each situation.
When should oil sampling be recommended? I offer it as an additional cost item on all surveys and strongly recommend it on all high dollar engines – diesels over 70 horsepower and “go-fast” gas engines. Other tests are also normally recommended on these engines to help assure the buyer/owner the engines are fully checked and, hopefully, will give good service.
Standard series engines that are readily replaceable with marine rebuilt units are not given the same attention unless the sea trial is not satisfactory. Pure economics and time constraints are the real determinants.
Drawing the samples – I use a 60cc syringe (approx. 2 oz.) and ¼” polyethylene tubing cut to a length about two inches longer than the dipstick. A fresh syringe and new tube is used on each sample to minimize the possibility of contamination between samples. The lab furnishes the sample bottles, the tubing is about 10 cents per foot, and the syringes are less than a dollar apiece at veterinary supply stores. All relatively inexpensive with no mess to clean up or store after the job is done.
The lab needs about 3 oz. of liquid to work with as this gives them enough for a full sample plus a reserve for retest if anything goes wrong or looks suspicious on the first test.
Most of the major diesel engine companies offer sample withdrawal kits and analysis by their laboratories as a part of after sale services. If you do a lot of a survey work on a particular brand of engine you may want to use this approach as they will have a large database that is product specific.
Engines that warrant oil sampling and have closed cooling systems also get the coolant sampled as part of the process. Large diesels in particular can develop major problems with potential loss of the engine due to the wrong coolant or contaminated coolant.
A one-time sample does not give a trend but it can be a very valuable tool in the surveying process.
A single blood test may not reveal a heart problem, but if it shows you have Hepatitis, corrective action is needed immediately!
James G. Merritt – SAMS® Accredited Marine Surveyor 1992
Tangent Development Co., Marine Division
1715 Harlequin Run
Austin, Texas 78758