There have been a number of postings recently about dirty fuel tanks (and water tanks). One method to gain access to the tank to clean the interior is with an access plate. Clarus Technologies of Bellingham makes an access plate which seem ideally suited for cleaning tanks for those that are mechanically adept. Their web site indicates their primary business is geared toward the tank cleaning business because their access plate isn't even mentioned! I suppose they made them as an adjunct to their main busines. I scanned the instructions that came with the 6" access plate that I just bought, which, by the way, has a 4" access hole. Yes, that will be a really tight fit for a hand or an arm. Installation of the access plate is just part of the project - cleaning, if done yourself, requires knowledge about working with hazardous materials which is a whole 'nother subject. So here goes...... For starters, "DANGER!" never drill a hole in a tank that had explosive gas. Consult your MSDS sheet with regard to fluids contained in the tank. Access Plate for Fuel Tank 6-in Access Plate installed Clarus 6” and 8” Access Plate System INSTALLATION INSTRUCTIONS Proper access to a tank often includes cutting access holes to help thoroughly clean of all parts of the tank, including around baffles and in corners. The Patented Clarus Access Plate Kit is a high quality, easily installed device designed to positively seal an access hole and to facilitate future access. Access Hole Preparation 1. Very Important! Be sure to complete access hole preparation before beginning tank cleaning. 2. Identify flat section of tank where access is necessary, making sure fluid level is below the area where holes will be cut. Also, make sure the access hole location is not over a tank baffle. 3. Hold front plate against tank and mark the six stud holes (6" plate) or the eight studs (8" plate) with a permanent felt tip pen or a scribe. 4. Using a punch, mark the center of the stud holes previously outlined in Step 3. This will center the drill bit. NOTE: This step is very important to accurately drill the stud holes 5. Using cutting oil and a 3/8" drill bit, drill the stud holes. USER'S TIP: We recommend Black & Decker brand "bullet" bits for fast, clean drilling and minimal wandering. 6. Locate the center of the hole-saw cut by drawing lines across two pairs of opposite stud holes and mark an "X" where the two lines intersect. (See diagram for 6" plate at right. Use same method for 8" plate.) 7. Drill a 1/4" hole on the center "V. 8. Cut the access hole with a 4" hole-saw (6" plate) or 6" hole-saw (8" plate) using the 1/4" center hole for the pilot bit. Use plenty of cuffing oil and operate at a slower speed to prevent overheating the hole-saw. USER'S TIP: Use a heavy duty drill (1/2" chuck) with side handle to prevent twisting from hole-saw torque. USER'S TIP: To make cutting the access hole easier, tilt the drill approximately 10° to 15° off centerline so the hole-saw cuts on its side (instead of holding it flat). When the tank wall is penetrated by the side of the hole-saw, rotate the drill counter-clockwise, extending the cut in a counter-clockwise direction until you have completed the circle cut. NOTE: Be careful not to drop the cutout into the tank when the hole-saw cut is complete. Using a long pilot bit on the hole-saw will help. 9. Deburr the inside and outside edge of the cutout with a file, then clean the inside area of the stud holes with sandpaper (such as 120 grit, wet or dry) to remove any sharp edges on holes and to clean the surface for the inner gasket. Also clean the outer surface for the outer gasket. 10. Complete tank cleaning process. When finished, proceed to Plate Installation instructions. Plate Installation 1. Press inner gasket over studs on both backing plates. 2. Fold backing plates together, creating a "C" shape, and slip through the access hole. Push the studs of one of the backing plates through the stud holes in the tank. 3. While holding the studs of one backing plate through the tank stud holes, press outer gasket over the studs. This will prevent the backing plate from falling into tank. Repeat procedure for the other backing plate. USER'S TIP: To prevent a difficult retrieval of the backing plates if they are dropped into the tank, tie a string to the backing plates/inner gasket and remove after the first backing plate is secured by the outer gasket. 4. Place front plate over the studs and outer gasket. Place flat washers, then lock washers, then the nuts over each stud. Tighten nuts until outer gasket is compressed and is pushing out slightly from the edge of the front plate. DO NOT OVER TIGHTEN AND SEVERELY DISTORT THE GASKET! Make sure surfaces are clean. Do not use gasket compound! IMPORTANT: To prevent the threads from galling, use anti-seize compound prior to installing the nuts. The Clarus Access Plate Kit includes: 1 aluminum front plate 2 semi-circular aluminum backing plates with stud 1 outer gasket 1 inner gasket stainless nuts stainless lock-nut washers stainless flat washers Tool Checklist: q Drill q Punch q 4" diameter hole saw (6" plate) or 6" hole saw (8" plate) q 3/8" drill bit q 1/4" drill bit q File q Sandpaper q Felt Tip Pen (or other permanent marker) q Cutting Oil q Straight Edge q Anti-Seize Compound Replacement parts are available upon request. Specific design modifications are also available. Clarus Technologies, Inc 2015 Alpine Way Bellingham WA 360-671-1514 http://www.clarustechnologies.com/ I appologize for the poor quality of the diagram. It printed really good on paper but... Cost of the access plate at Doc Freeman's [http://www.docfreemans.com/] in Seattle was "around" $100. I paid less with my discount and I don't know what retail is.
