Tranny Fluid & Heat Exchanger

Nov 6, 2006
9,226
Hunter 34 Mandeville Louisiana
That is the high pressure fuel injection pump. It is lubricated by the oil in the engine... and to a small extent by the diesel in the plungers ..
The transmission is on the other end of the engine.
It looks like your engine stop control is disconnected..
 
Nov 16, 2012
1,001
Catalina 310, 2000, #31 31 Santa Cruz
Wondering if anyone on this thread has this transmission setup on their boat and if so, where do I find the drain plug as well as the measuring stick. I looked in my owners manual (universal Mx25) and nothing about where to look for these two items. Thanks in advance.
The transmission is to the left of the engine in your picture. Access is mostly from the aft berth, not much from the engine compartment.
If you’ve got the ZF 5M (HBW 50) tranny the drain plug is on the bottom, port side. But it’s real tough to access and hard to get anything under it to catch the fluid. I find it easier to just pump out the fill hole, which is located on the port top side. In this picture I’m looking forward with the a few of the aft boards removed. The fill hole is just under and slightly to the right of the stainless ring.
1620503368554.jpeg
Here’s the manual for that transmission.
 

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Nov 16, 2012
1,001
Catalina 310, 2000, #31 31 Santa Cruz
First, thanks to everyone for such wonderful help for this newbie. This is my first sailboat, and you have been a great resource. I'm looking forward to when I can help others, but for now, I have another question. Yesterday I changed the tranny fluid for the first time, and as the prior owner told me, it's a challenge. A friend helped me move the engine block to have enough room to remove the dipstick bolt (photo attached). We even had to remove the bolt that holds the Heat Exchanger in place. I've surmised that I have model 80 based on the manual, but there's no indication on the actual tranny near the serial number), so I put in 1 quart of fresh tranny fluid. There is only ONE marking on the dipstick itself (manual says there should be two - LOW/FULL). When testing, the ATF level was about 2/3 up the dipstick, which is much higher than the diagram in the manual suggests.

Two questions:

1) Is 1 quart of ATF about right?
2) Does everyone have the issue of having to remove the bolt to pull the engine block to remove the dipstick? Any advice?
The identification plate for your tranny is just to the right of the fill hole. You may need to clean it up to read, and I had to take a picture with my phone to figure out what it said (terrible viewing angle). It sure looks to me like it’s the ZF 5M (HBW 50), not the PRM 80.
 
Jun 2, 2018
19
Catalina 28 mk ii Port Orchard
If its a ZF5M and you put a quart in, then you way overfilled it. Capacity is 11 ounces (0.3 quarts). From your picture, I would say it is definitely either a ZF5M or ZF10M (capacity 13 ounces for a ZF10M). The dip stick is on the wrong side for a PRM80.

You are supposed to measure it with the dip stick just resting on top of the threads; not screwed in.

I extract mine with a small hand pump, and carefully measure the fluid refill in a measuring cup. Too much will do bad things to your gearbox.

My 25XPB started out life with a ZF10M, and a previous owner swapped it out for a ZF10M.
 
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