Oil Pressure Gauge Troubleshoot

[RTN1]

Greetings All,

Westerbeke 55A with 1100 hrs on a Saga 43 sloop. Engine has always run great and has had all scheduled maintenance, but I've been stymied by a problem with the oil pressure gauge.

Several months ago I noticed the gauge was pegged as soon as the engine started, and held there regardless of engine speed. The first thing I did was to borrow an analog gauge, attach it, and verified that oil pressure was fine at around 60 psi. There is also a separate low pressure warning buzzer that sounds for 1 - 2 seconds at startup until there is pressure, and the engine is not using any oil or running hot, so I'm confident this is just a gauge problem.

A likely cause was the sender unit so I replaced that; no change.

Confirmed continuity in the orange sender wire.

Today I replaced the gauge. Now the new gauge reads zero at all rpm, although there is a very slight uptick in the needle when the engine starts, so I know the gauge is energized.

If the sender is new, the gauge is new and the sender wire is ok, what else could be wrong? And why is one gauge reading maximum, the other reading minimum, while a remote gauge reads normal???

Thanks for any ideas,

Roger
Laguna Beach, CA

[DeepFrz]

Check the ground wire.

[Blue Stocking]

Does the gauge and the sender have similar ohms ratings.

[delmarrey]

There are Euro gage systems and USA systems. Gordmay posted a chart in the gallery for resistance values. Check it out.

[RTN1]

Many thanks to all for the quick replies, and especially to GordMay for the wealth of info he posted in the galleries.

One question on the resistance measurement for the oil pressure gauge shown in chart E-1218t: There are two rows for Oil Pressure, with very different resistance #'s. Does anyone know which would be appropriate for my Westerbeke Admiral's Panel?

[delmarrey]

There are single and dual station gauges. Go to this thread and read the first post.>>>> http://www.cruisersforum.com/forums/...sting-645.html

[RTN1]

Still working to find a solution to this problem. My local Westerbeke mechanic felt it was likely an incompatibility between sender and gauge. So I've now installed 3 different senders and still have the same issue of the gauge going to maximum as soon as it's energized and while the engine runs.

I have replaced the sender wire with no effect.

I have confirmed that the ground is ok by running a separate wire for that to my main ground plate. No change. Also, the tach and water temp gauge work fine and they use a daisy chained ground wire from the oil gauge.

I have a new gauge coming next week. What else could it be???

[Matt Johnson]

If you findout, let me know. I have the same issue with my Westerbeke 30b three.

[Dulcesuenos]

We have mechanical gauges on both of ours. Less headaches.

[NoTies]

Is it a VDO type sender, cylindrical with 2x screw connections?

[bobconnie]

Get a mechanical gauge to at least ck it with ! I always use mech gauges and use a long tube if needed if I cant I mount it so I can see it quickly! Just a thought

[perchance]

Your mechanical guage is reading 60 psi so add resistance to the circuit till your digital guage reads the same. Had to do this for a power boat I worked on.

[RTN1]

Pete,

Sender has a single center screw on the back for the orange sender wire.

[NoTies]

Originally Posted by RTN1

Pete,

Sender has a single center screw on the back for the orange sender wire.

OK, that rules one thing out & I'm out of ideas. No chance it's an alarm sender rather than a gauge sender I guess?

[RTN1]

The alarm sender and buzzer work fine. It's just the gauge/sender that's the problem. Trying a new gauge this weekend....