How do I drain the PT&T system?

[essdee]

Query: Is there a straightforward way of draining the PT&T system to get rid of the old fluid and replace it with a fresh supply? <br /><br />Engine Specs: Evinrude 1997/ V4-90hp/ 1632cc<br />PT&T Specs: Vertically mounted (conventional)<br /><br />Background:<br />1. Pre-owned engine, previous owner somewhat tardy. Using my weekends etc. to clean-up and tune-up.<br />2. Have the original user manual plus Seloc Repair Manual. Both mention that fluid must be replaced if milky or unclear but neither suggests a simple way to do so. The fluid appears dark brown but does not contain any water or particles.<br />3. Seloc describes an elaborate procedure for a complete over-haul of the PT&T system but everything is working fine and I just want to fill her up with new fluid.<br />4. Have Googled extensively and searched many forums too... need an answer from someone who's been there.<br />5. This is my first post here and it's about my first boat, so I thank any advice in advance : )<br /><br />Regards,<br />evindude

 

[OBJ]

Re: How do I drain the PT&T system?

Welcome evinrude!<br /><br />I think the question should be, is there an easy, clean, unmessy way to drain the fluid.....not really.<br /><br />Probably the easiest way is to remove the manual release valve and let it drain out through the manual release passage. But to get to the release valve for removal, the unit has to be removed from the engine so that the valve retaining ring can be removed.<br /><br />Manually working the rams up and down will get a lot more of the old fluid out. To flush, replace the manual release valve, refill the unit and work the unit up and down to get the clean fluid through the unit. Then drain again. Lot of fluid to use and a lot of mess.<br /><br />Problem is, you still may not get all the older fluid out and if there is still junk laying about, you may not get all of it out. <br /><br />One more thing, do remember that the unit is almost always under pressure, be very cautious of removing any line or manual release valve. The fluid could burst out and give you a bath. Losening a hydraulic line connection will relieve the pressure.

 

[DHPMARINE]

Re: How do I drain the PT&T system?

There is also a filter under the motor on the unit that can be checked.<br />BUT as a rule,I don't mess with a TNT system unless there is a real problem.You may dislodge 'some of the junk laying about'.If it sticks in a valve or something,now you may have created a real problem,and have to rebuild the whole thing.<br /><br />DHP

 

[essdee]

Re: How do I drain the PT&T system?

Wow! I doubt I would have received faster responses even if I was paying for the support.<br /><br />Thank you to both OBJ and DHPMarine for their advice. I had ruled out the manual release valve for the same reason i.e. 'junk lying inside' and since the valve is not the lowest exit in the system it would not be a perfect flushing.<br /><br />I was hoping for a master drain plug somewhere in the system but your responses confirm the visual check I made earlier i.e. there is none!<br /><br />All said and done, I guess for the time being I'll refill as prescribed by the manual and save the big operation for when I'm taking the engine apart for a full overhaul (when and if that becomes necessary).<br /><br />Seasoned advice is in short supply over here in Bahrain (the small island off the coast of Saudi Arabia, due to host the first race of the 2006 F1 season). At my local marina, it is common to see boaters test-fire their engines on land before entering the water. As per the manual and everything else I've read, this procedure (even if only for a few seconds) can wreck the impeller. Yet no one seems to mind out here. I've even seen anodes painted over!<br /><br />Anyhow, thank you for the welcome and the prompt support. I'll be sure to respond in kind whenever I can.<br /><br />Regards,<br />evindude