[C320-list] Hurth Transmission Fluid Replacement

[Alan Goodman]

Frank - I have hull #67.  I have the Perkins engine / Hurth gear box combo and changed my transmission fluid this fall.  IT USES ATF, NOT LUBE OIL.  I used my oil dipstick extraction pump to remove all the old fluid through the fill / level check fitting on top of the gear box.  Be sure to clean the area prior to loosening the dip stick nut.  Also be gentle with the treads, I believe the housing is aluminum (i.e. soft and easy to mess up the threads of the harder dip stick steel threads.  Also, be aware there is a rubber 'O' ring mounted at the top of the dip stick (don't loose it, but insect for cracks and replace if necessary).  Also, I needed to 'fish' the suction tube around inside the transmission case to get to the very bottom of the sump ... a good thing to do (IMHO) since the lube capacity is so small starting with 'virgin' ATF would seem to be important.  You'll need a long tube on the funnel to pour in the new ATF fluid without making a mess, at least 4 inches long.  Also, measure the fluid out before pouring into the tranny, clean ATF is virtually impossible to see on the dip stick, so knowing you are starting with the correct amount is a great way to make sure you do not over or under fill (which the manual says is critical).  I don't recall the specific type of ATF I used, but the bottle is on my boat and I'll be going back to the boat in the next 2 weeks and can look if you like.  Lastly, remember the ATF fluid level is checked without threading the dipstick into the case, only resting upon the threads.  Contact me off list if you need some more info or specifics.  BTW, I have the original install/shipping placards, and one clearly instructs that when sailing with the engine off, place the Hurth transmission in 'reverse' or 'neutral' AND NOT IN FORWARD.  I use neutral so as to allow my three blade cruising fixed prop to 'free wheel' and minimize drag.  There has been substantial discussion herein regarding the correct tranny position while sailing and other manufacturers may have different instructions.  Let me know if you want me to photo copy and send you the placard for your records (or maybe post in the technical section of the forum?)  Alan Hull #67 Holland MI


> 
> Message: 9
> Date: Tue, 29 Mar 2011 00:22:11 -0400
> From: Amshd2 <amshd2 at aol.com>
> To: C320-List at Catalina320.com
> Subject: Re: [C320-list] Hurth Transmission Fluid Replacement
> Message-ID: <8CDBBE001866041-17B0-40FB0 at webmail-m136.sysops.aol.com>
> Content-Type: text/plain; charset="us-ascii"
> 
> 
> The Perkins with the Hurth Gear box in the 93- early 95 models uses Transmission fluid.  I have hull number 30 with that set up.  Manual calls for ATF Dextron II .
> 
> TONY 
> 
> 
> 
> > 
> > In a message dated 3/28/2011 3:35:30 P.M. Central Daylight Time, 
> > res07290 at verizon.net writes: 
> > 
> > 
> > I am planning to change the fluid in the Hurth Transmission this > spring. 
> > Looking through the owner's manual I have for my 1994, The > recommended 
> > fluid 
> > replacement is Type "A" transmission fluid. I can't find it at any > local 
> > auto parts store. 
> > 
> > I have heard that Dexron III replaced Type "A", but I can't find > that in 
> > writing anywhere. I called ZF Marine for advise, but have not > heard back 
> > from them. 
> > 
> > Any ideas here?? 
> > 
> > All help is greatly appreciated. 
> > 
> > 
> > Thanks in advance. 
> > 
> > Frank Drahos 
> > Belles & Whistles #98 
> > 
> > 
> > 
>  
> 
> 
> 
> End of C320-list Digest, Vol 1067, Issue 1
> ******************************************