Posted by NCWayne on July 13, 2014 at 10:07:51 from (173.188.169.54):
In Reply to: Hydraulic cylinder? posted by George Marsh on July 13, 2014 at 04:51:33:
When you look at the head of the cylinder, where the rod comes out, the first part you see is a wiper. It"s designed to do exactly what you are asking, and wipe debris off the cylinder rod. The next piece in is typically going to be the seal that actually keeps the oil pressure from blowing out of the cylinder. Yes they do make covers for the rod, but they are designed more for really extreme environments that your usually not going to see with a typical piece of equipment.
I"ve built hundreds of cylinders over the years, and, like you say, the majority of them only "needed" the wiper and the rod seal. The cause of the leak is rarely dirt, etc getting to the seal, it"s simply that, like any other plastic type part, the seal gets old and hard and can no longer seal. In fact I have seen some that have all but disintegrated. That said, when the wiper, which is exposed to the air and sun, gets hard and quits wiping properly, it will then allow dirt and debris to get to the seal. With the seal already hard, it is then easier for it to get eat up and begin to leak due to the contamination. Too, if there is damage to the rod, then a standard U cup type seal is only going to last so long before the damaged place sliding past it cuts the seal and causes a leak. That"s one of the times when the old V ring packing is far superior to the newer U cup type seals.
In the end you"ve got to pull the cylinder apart already to change just those two parts, so why not spend the few extra dollars to buy the kit and do a complete rebuild. Granted I have seem many cylinders where the piston seal/seals don"t appear to be worn, but even if the actual seal piece looks OK, it doesn"t mean there isn"t a few thousands of wear in it, or that the rubber (like an O-ring) energizer behind it hasn"t taken a set and/or gotten hard (depending on seal type). On that type you can"t see the energizer ring without damaging the actual seal to get to it.
In the end, when you think about it, all of the seals are the same age. If you had to get separate parts, that means trying to match up the piston seals, the rod seal, a buffer seal on the rod (if it has one), as well as the O-ring and backup ring that seals the head to the barrel. Given that there are multiple different types and sizes of each one, expecting someone to have everything in stock all at the same time is asking a bit much. In other words by the time you order parts, pay shipping, etc you"ve got more into the parts than the cost of a complete kit.
Ultimately it"s cheap insurance to do the job right while your already there and replace everything before the next "weak link" causes you problems a few months down the road.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Product Review - by Staff. When we finally checked out the 3000 PSI North Star, the whole story chaned. This unit was equipped with an 11 HP Honda engine with fuel shutoff, adjustable flow and optional syphon degreaser dispenser. It didn't have a pressure release or electric start to facilitate easy starting but according to the instructions, simply pulling on the trigger while cranking was sufficient. This method of starting proved more than adequate and kept the cost down on the unit. It had all the important
... [Read Article]
Latest Ad:
1964 I-H 140 tractor with cultivators and sidedresser. Starts and runs good. Asking 2650. CALL RON AT 502-319-1952
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
