[C320-list] Oil Pressure Alarm

[Warren Updike]

This year I replaced the pedestal alarm. The original alarm worked intermittently; but, more recently mostly didn't work. Yes, there are a lot of wires on it, 7 in total, 3 on one terminal and 4 on the other (as I remember.) Took a picture before disconnecting. I couldn't get the old alarm out as the outside ring that screws on wouldn't turn. I had to resort to cutting through it and forcing off with pliers. It was a bit of a pain getting all those wires back on; but, once done it worked like a charm. 

As for engine mounted senders, different engines may have different arrangements and types of senders. On our Perkins, from what I can tell, there is a coolant temp sender (temp gage) and a separate over-temp sender (LED and alarm.) There is only one sender for the oil pressure LED and alarm (I think.) On some (Yanmar??) there may be an oil pressure sensor and a separate sender. Be sure to dope out what you have. Also, some senders may be always on or always off except when sending.  

Warren and Pattie Updike
1994 C320 "Warr de Mar" #62
Middle River, Chesapeake Bay



-----Original Message-----
From: Troy Dunn [mailto:troutwarrior at gmail.com] 
Sent: Monday, July 11, 2016 8:38 PM
To: C320-List at catalina320.com
Subject: [C320-list] Oil Pressure Alarm

After extensive research on parts and reading through the various trials
and tribulations on this forum dealing with the intermittent oil pressure
alarm and whether or not having a working blower matters, I opted to
replace both the finicky alarm and the non functional blower switch, the
latter of which had corroded so badly it would not budge.

Removing the panel is a fairly simple affair.  Just 6 screws and a little
bit of trickyness getting it away from the pod through the wheel.  I had to
remove some sealant from the backside of the switch and alarm in order to
remove these two devices.   After confirming that the blower still works by
connecting the two switch wires and briefly turning on the ignition, I
replaced the switch and problem 1 solved.

I moved on to replacing the alarm.   A lot more wires here, so I got out my
label maker just to ensure I put everything back where it belongs and also
to make use of that label maker since so far the only thing it has
been good for was labeling the locking clutches for all the running
rigging.   Five minutes later I turned the key in the ignition and
voila...nothing happened...grrrr...

I moved on to get a good look at the pressure switch on the engine.   Down
below with the stairs lifted and the cover off now I'm staring at what
appears to be the pressure switch according to all the pictures I could
find on parts websites.  At the time it was not obvious to me that I could
simply pull off the wire from the spade connector.   I noticed some
corrosion on the ring side of the terminal where there is a screw.
Turning this screw does not seem to loosen the connector I might mention,
so I gave up on that approach, called it a day and went sailing instead of
messing around with an alarm that only works on half the Catalinas out
there anyway if the message boards are any indication.

Leaving Havre De Grace usually entails a 30 minute motor down the channel,
but the winds were unusually cooperative on Sunday and once we had the
sails up, we cut the motor...and of course the new low pressure alarm was
screaming like a banshee.    I shut off the ignition and kept sailing.

So now I'm re reading all the threads, kinda kicking myself because I know
the oil pressure light works, but I can't recall if it only works when the
alarm works or not.   My sense is that with an older engine, the switch
gets gunked up over time and doesn't operate correctly.   Then when you
run, the engine heats up and all that gunk becomes more viscous and then
when you shut down, the switch works.    So that's my running theory until
I can confirm that the light is only lit if the alarm is going off as well.
  Kinda hoping this is the solution because nothing else makes much sense
that I can figure.  Also hoping that the pressure switch is above the
normal oil level in the engine when cool so it isn't a mess to replace.

The only other 'repair' we worked on this weekend was confirming the oven
temperatures seem to be about right.   When the boat surveyed we could not
get the oven to light off.  A couple of weeks ago we got the oven working.
This weekend we confirmed the temperature must be about right by baking
cookies while running downwind up the Sassafrass at 6.5 kts. We burned the
bottoms on the first batch because we placed the tray directly on the
bottom of the oven.  Once we figured out that the tray would fit on the
rack...life was good.

Troy and Kim Dunn
Hull #514   New name coming...got some ceremonies to deal with...graphics
arrived today
Tidewater Marina, Havre De Grace, MD