Com-Pac Yacht Owners Association

Com-Pac Model Specific Discussions => CP-27's => Topic started by: TopsailB on November 02, 2022, 02:53:43 PM

Title: Oil Pressure Gauge for Universal M2-12
Post by: TopsailB on November 02, 2022, 02:53:43 PM
I?ve never been comfortable with only idiot lights for engines. Since I purchased my CP-27 I?ve slowly been working through a list of projects, including removal of the ammeter. Instead of installing a voltmeter, since there is a Victron battery monitor down below, I decided to replace the ammeter with an oil pressure gauge. With diesel engines, I?m more concerned with oil pressure than voltage.

There were a few challenges, mainly that the available space to replace the oil pressure switch with a tee for both the switch and a pressure sender just isn?t there on the engine. After pondering for a while, I finally came upon a reasonable solution. The existing switch was removed (the oil filter had to come off for decent access with a large socket) and replaced with a GlowShift 1/8 BSPT Male to 1/8-27 NPT Female Gauge Sensor/Sender Thread Adapter/Reducer. A crush washer was used to make sure the seal to the block was tight. Since the switch and sensor must be connected to ground to work, a Grainger Flexible Hose Assembly Item #4DXP5 with a braided stainless steel cover was used. A standard 1/8 npt brass all female tee was attached to the hose, and the new Kubota switch and Faria gauge matched sender were attached.

And yes, the gauge is a bit skewed in the picture, but that has been remedied. All in it took about two hours to remove the ammeter, re-wire directly to the starter and install the oil pressure gauge. The total was about $100 for all parts: sender adaptor/reducer, hose, tee, switch, sender, gauge.
Title: Re: Oil Pressure Gauge for Universal M2-12
Post by: deisher6 on November 03, 2022, 09:20:48 PM
Good & Smart move TopsailB. 
It is a great improvement.
I never was comfortable with the standard panel on either of our C-27's.  I recall in the manual that there is an alternate panel that was an option.  I tried to find one at a reasonable price, but gave up to other projects.
regards
charlie

Title: Re: Oil Pressure Gauge for Universal M2-12
Post by: Cruzin on November 03, 2022, 11:34:36 PM
I had seen somewhere that there might be some safety issues with the original ammeter wiring harness, I have no idea if this is correct or not. Can you confirm the safety issue? If I just removed the ammeter, is this a pretty simple process? My electrical knowledge is very limited.
Thanks
Dale
Title: Re: Oil Pressure Gauge for Universal M2-12
Post by: TopsailB on November 04, 2022, 06:52:02 AM
The potential exists for issues due to undersized wire, length of run, poor connection in the trailer plug, and the amps flowing through the charging circuit from the alternator. Below is a great explanation with steps to remove the ammeter circuit.

https://pbase.com/mainecruising/universal_wiring_harness_upgrade

I removed the alternator, and disconnected the orange and red wires from the ammeter. The wires were traced-one goes to the alternator, the other to a lug on the starter solenoid. The alternator wire was removed, the wire connected to the starter was shortened to about 8 inches and a ring connector added. Then it was connected back to the alternator. The alternator was reinstalled, and the ammeter gauge removed from the panel.
Title: Re: Oil Pressure Gauge for Universal M2-12
Post by: Cruzin on November 05, 2022, 08:55:56 PM
Thank you!

Dale
Title: Re: Oil Pressure Gauge for Universal M2-12
Post by: wes on November 06, 2022, 07:59:47 AM
Very nice upgrade. I too removed and rewired the alternator output to get rid of the problematic ammeter path.

RC Collins' excellent article on the Universal control panel wiring at marinehowto.com was an inspiration. Based on his concerns about overheating and fire risk, I removed the molex connector entirely and hard-wired all the connections from engine to control panel. After all, that connector is only there for the convenience of the boat builder - to allow different optional cable harness lengths depending on control panel location on various boat models.

Wes