Volvo Penta Tilt/Trim....mixing fluids?

kayakndave

Seaman Apprentice
Joined
Jun 22, 2004
Messages
46
Just purchased a new tilt/trim pump for my 1988 Volvo Penta AQ171C with 290 outdrive. Here's my dilemma. The decal on the old pump says fill with 10W-30. The new replacement says fill with dextron ATF. The problem is the trim cylinder fittings seem to be impossible to get to in order to purge out the old fluid (I'm assuming it's 10W-30). A marine mechanic told me not to worry about it, just fill the new pump with dextron, and install. What do ya'll think about this? Can you mix the two fluids? I sure don't want to ruin a new $400 pump! Any ill effects? All help/suggestions greatly appreciated!
 

kayakndave

Seaman Apprentice
Joined
Jun 22, 2004
Messages
46
Re: Volvo Penta Tilt/Trim....mixing fluids?

Thanks for all the input everyone.....
 

Peter J Fraser

Chief Petty Officer
Joined
Jun 22, 2003
Messages
598
Re: Volvo Penta Tilt/Trim....mixing fluids?

It will work BUT if you disconnect the rams where they attach at the leg and pump the cylinder manually through the stroke a few times you will purge the old fluid out of the cylinders.<br />Do this before you connect up to your new pump by connecting some plastic hose to the end of the trim cyl hoses you will also be able to catch the oil into another container and dump the old oil to waste.<br />Connect up the hoses onto the pump unit and reconnect the cyl's onto the leg. Fill the resevoir with ATF and just keep cycling the system up and down to the limits of the travel until all the air is out of the system totally.<br />Keep an eye on the fluid level in the resevoir though while you do this to ensure that you dont suck air in again if the oil level gets too low.<br />The system will benefit from a fresh oil rinse.<br /><br />Regards<br /><br />Peter
 

kayakndave

Seaman Apprentice
Joined
Jun 22, 2004
Messages
46
Re: Volvo Penta Tilt/Trim....mixing fluids?

Thanks Peter for taking the time to help me out. What you advise makes total sense. The problem however, is that the fittings to the cylinders look impossible to get to unless you remove the outdrive! I wonder if the rams will eventually purge through the pump by removing the return line while under pressure (or trimming the motor up)? Nothing's ever easy is it...........
 

Peter J Fraser

Chief Petty Officer
Joined
Jun 22, 2003
Messages
598
Re: Volvo Penta Tilt/Trim....mixing fluids?

Sorry for delay in reply, I have been away for a few days and I missed your reply.<br />Can you get to the hose fittings at the pump valve body? If so then disconnect your hoses there instead of at the cylinder end. You may need to aquire an 'open box wrench spanner' to get the fittings undone, usually 1/2" or maybe 9/16" AF sizes. Try for 6 point and not 12 point as the former supports the tube nuts better.<br />The oil will change in the cylinders with constant cycling up and down but you would need to change the contents of the resovoir a couple of times to complete the change and freshen up the oil.<br />Good luck,<br /><br />Peter
 

kayakndave

Seaman Apprentice
Joined
Jun 22, 2004
Messages
46
Re: Volvo Penta Tilt/Trim....mixing fluids?

Thanks Peter....Did it, and she's done! Works like a champ. Thanks for all the help/advice everyone.
 
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