Report on the use of Utex U-Pak stuffing box packing. U-Pak, http://www.utexind.com/products/upak/,is a type of injectable packing. My problem was my propeller shaft stuffing box packing was leaking profusely after each trip. Even though I tightened it up to the proper drip-drip prior to every run, after shutdown the leakage always exceeded the acceptable limit. I had come to the conclusion that I needed a mechanical seal. The normal ones available for the marine market required the removal of my propeller shaft which is 3 inch in diameter and 14 feet long. In addition it required removal of the rudder which is a labor intensive job and would need to be done in a yard. So, I investigated split seals. The one Utex Ind. makes looked good so I called them. The fellow I talked with (Sandy, 888 883-7579), talked me out of the expensive ($2300+, plus machine shop work for adapters and spacers to fit it onto my stuffing box) mechanical seal and suggested their U-Pak system using type 400-HP stuffing box packing. After cleaning out all the old packing I installed one ring of graphite impregnated PTFE packing in the outboard end of the stuffing box. This ring acts as an anti-extrusion ring to keep the U-Pak in the stuffing box. One should be used in the propeller end of the box and one at the inboard end of the stuffing box. Utex sells the packing but I got mine at the yard I hauled out in. It's black, slippery and costs approximately $18/ft. The U-Pak is sandwiched between the two packing rings. My stuffing box is relatively short so I have about two and a half inches of U-Pak (remember this is a four inch shaft). I rolled the clay-like U-Pak into "snakes" to fit the gap between the stuffing box and shaft and tamped it in with a wooden stick and hammer. I repeated this procedure until I just had room for the inboard PTFE ring and about 1/4" for the bronze squeezer part which presses against the inboard PTFE ring. This depends on how your packing gland is designed. I snuggled up everything and several days later we launched. Do not over-tighten on the initial installation. After splashing we went on a day trip from Gloucester to Newburyport. At Newburyport the leakage was much less than with the standard packing. I adjusted the U-PAK again to a steady drip and haven't touched it since, now over 1500 miles later. The U-Pak material has completely solved my problem, which had persisted for years. I am grateful that Sandy at Utex steered me away from the split mechanical seal and recommended U-PAK as a solution to my stuffing box woes. I suggest to anyone who would like to try this packing to order a one Kg tub of the Utex U-PAK 400-HP packing. Utex can sell you the graphite impregnated PTFE packing for the rings or you can get it locally. The kit does normally come with an expensive hydraulic "grease gun" to add more packing to the stuffing box through a button-head fitting while the equipment is running in order to minimize down time. This was not needed for my application as there was not enough depletion of the U-Pak material to justify the gun so I returned mine. I give my unreserved recommendations to the U-PAK material, it has worked like magic for me. I must add that Utex Ind. has not compensated me in any way for this report and I deliberately did not inform them that I was going to write a review until all our dealings were finished. Norm S/V Bandersnatch Lying Julington Creek FL 30 07.72N 081 38.4W _______________________________________________ Liveaboard mailing list [email protected] To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to [EMAIL PROTECTED] To unsubscribe send an email to [EMAIL PROTECTED] The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/[email protected] The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
