How much transmission fluid?

[Tashahacker]

Hello helpful Catalina owners!

We have a Universal M-25 and I've just discovered the existence of the transmission dipstick and have managed to extract it. But I can't find any instructions on the fluid in our manual. If you don't mind, I have a few questions:

1) There is a line at the bottom of the dipstick and the fluid level is current halfway between the bottom of the stick and the line. Where should the fluid level be? (Someone warned me not to put too much transmission fluid in).

2) I've read on the pages here on C34 that some people prefer to change their transmission fluid by sucking it out of the dipstick area. Others use the drain on the bottom. Is there a reason why I wouldn't use the drain on the bottom?

3) What is the amount of fluid I should put back in after draining?

4) How often should I be changing the transmission fluid?

5) What transmission fluid is recommended?

Thanks so much for your help!

As always, I really appreciate all your expertise!

Sincerely,

Tasha (Turf to Surf)
s/v Hideaway

[Stu Jackson]

Transmission Fluid 101   http://c34.org/bbs/index.php/topic,6417.0.html

You might want to check the C34 Tech wiki, too.

[Ron Hill]

Tasha : If you look in the back of your Engine Manual there is an entire section devoted to your
Hurth 50 transmission.  It contains the answers to your transmission questions, but one.

I sure that you saw on our message board discussions that most of us suck out the XM fluid because it eliminates the possibility of a future leak. 

hope this helps. 

[Jeff Kaplan]

Tasha,

On my '86, I change the t-fluid each spring.  In the fall, I fill the case to the top, approx. 1 qt., thru the dipstick hole. I use Dextron ATF.  In the spring, I use a pump to remove the t-fluid, save it in bottle for next fall.  I then refill with new fluid,approx. 9-10 oz.  All done thru the dipstick hole. I use a 3/8 ratchet with a 12" extention rod with socket to get to the dipstick nut. I forget the size of the socket, either 9/16, 5/8 or 13/16.  I keep a full tool box on board, no Sears on the water. Easy job, a little time required.  Good luck.  You can contact me with any questions about the boat, I have replaced or updated just about everything  except the engine/transmission... Jeff

[Ken Juul]

The transmission works on the friction principle. The material that provides the friction wears off and settles in the bottom of the transmission.  To help extend the life of the trans, many of us try to keep the fluid as clean as possible.  The trans is also lubricated by the splash method.  For long layups, many folks feel it is better to have it it full of fluid so nothing dries out.  As many different methods as owners.  I usually suck it dry and fill to the brim in December when I winterize.  In the spring...actually tomorrow this year, i suck the excess out and am ready for another season.

If you haven't made it through the 101 series yet.  Fill with Dexron to the line on the dipstick,  you are low from your description.  I put a piece of tape at the correct length on my siphon tube.  Fill the transmission up, hold the mark at the top of the case and suck till I get air.

[Ron Hill]

T : Follow Kens' advice and I agree that yours sound low.  Also make sure that the transmission dip stick is NOT screwed in when ckecking for the correct level (just like your manual states).

An important thought!!