The Big Twin EVO’s are easy; because the oil filter is in the return oil path, all you have to do is leave the filter off and run the old oil out the filter mount and into the drain pan.
2006 Dyna’s and all ’07 and later Twin Cam A’s no longer have external oil lines, so this “system” wouldn’t work for them.
Twin Cam’s with the external lines can be done without the “system”. Simply remove the return line as shown in the video and install a short piece of 3/8” ID hose run into a drain pan. With the oil filter removed and a sump full of fresh oil, start the engine for a couple of seconds to “burp” out the old feed oil. Install a new filter and restart the engine, running it until clean oil flows out the return hose. This method requires an additional quart of oil.
Replace the band type hose clamp with a worm gear type clamp at the crankcase. After a number of oil changes, the hose may become frayed at the end from R&R so when necessary you should replace the formed hose .
Softail models can be done as shown in the video without the filter bypass. You can elect to burp the feed as described above or not; the volume of old feed oil in the pump and passages is minimal. The late model machines running hydraulic tensioners and plain cam bearings are more sensitive to low oil pressure than the earlier engines are so you may want to skip the burp on these machines.
Another method that seems to work just as well is to drain the oil and put just one quart of oil in the sump, then run the engine in the shop for 90 seconds, drain and refill the sump.
I have used both of these methods on my Twin Cam machines and I would always run the old oil out of the filter mount on my EVO’s and Shovels.
djkak
Author
Topic: Scavenger Oil Change System (Read 3799 times)