Oil pressure switch failure. Is it common?

[bigbikerrick]

Hello Folks, I have had two of the oil pressure light switches readily available from the usual suspects fail. My oil light on the dash does not illuminate when turning on the key, but grounding the wire terminal does illuminate the light.  Has anyone found a generic switch that can be substituted, and is locally available , from autozone or Oriellys?  I  would imagine something with a metric thread can be substituted.
Thank
Rick D.

[Antietam Classic Cycle]

https://www.thisoldtractor.com/moto_guzzi_loopframe_oil_pressure_sending_unit_cross_references.html
https://www.thisoldtractor.com/moto_guzzi_loopframe_oil_pressure_sending_unit.html

[bigbikerrick]

Thank you very much, Charlie.
Rick.

[guzzisteve]

The one on my Cali2 was off for over 20yrs, never bothered me, I know the bike since new. I put one in last year. Seen them fail a week later, so ya know. Seen em fail after hitting a pot hole too.

[bigbikerrick]

Yes Steve, Its pretty ridiculous how crappy these switches are. Thats why I thought I would try my luck with something from the auto parts store.  In all the years I have owned 4stroke japanese bikes, I dont recall a single failure of the oil pressure monitoring/ warning system.
Rick.

[Wayne Orwig]

I'm convinced that that mainly fail due to water getting in them.
I used to have them fail often. After putting a rubber boot over them, they no longer failed.

[bigbikerrick]

I think you may be correct , Wayne. I remember on a couple of other Guzzis , mostly V 11 sports, that  everytime I washed the bike, the oil pressure switch would "act up" until it dried out real good. Mg cycle sells the little boot. I will make sure to install that.
as always ,great advice.
thanks
Rick D.

[Antietam Classic Cycle]

I'm convinced that that mainly fail due to water getting in them.
I used to have them fail often. After putting a rubber boot over them, they no longer failed.

I had the opposite experience - the boot supplied by Guzzi didn't fit tightly on the wire, but did on the sender, allowing water to collect. Dead sender in short order. Stopped using the boot, no more failures.

[bigbikerrick]

Thats interesting, Charlie. Maybe the solution to water intrusion would be to apply some good quality heat shrink tubing to the sensor/ wire connection. For sure , I will be covering that little sucker, when I wash the bike!
Rick

[bigbikerrick]

I already ordered a replacement switch, and boot  from MGC, but next time, if it goes out ,I think I will try my luck with the NAPA Echlin OP 6065. Its got a spade connector, but thats fine.
Rick

[Mr Revhead]

They have a tiny vent hole in them.
If water gets j  there they fail.
After advice from here I put RTV over the hole on my third one.
30ks and 6 years later its still there

[Wayne Orwig]

I had the opposite experience - the boot supplied by Guzzi didn't fit tightly on the wire, but did on the sender, allowing water to collect. Dead sender in short order. Stopped using the boot, no more failures.

Odd. Mine are the opposite. Very tight on the connector, and maybe a bit loose around the sender..

[bigbikerrick]

Where is the vent hole located? I did not see any obvious vent hole in mine that failed. I tried poking a stiff wire into the oil hole, and flushed with carb cleaner spray, hoping to resurrect it. No Bueno!
Rick D.

[Mr Revhead]

On the upper face of the widest part

[Tom]

One for a VW bug would work.  The tacky rubber tape works too.  Both from the old Moto Guzzi National Owner's Tip books.  (cheap content)   

[bigbikerrick]

I will look for that vent hole when the new one I ordered gets in. I will encapsulate that sucker in silicone sealer, if I have to!   The VW bug one sounds  like a good alternative, Tom. I dont recall that sensor ever failing on any of my air cooled bugs.

Rick D.

[Tom]

   A number of Bosch components will also work on Loops. eg coils.  Fuel pumps for FI., coils etc.   

[testa_di_formaggio]

The rubber boots used on the switches flip flop around in availability, as well as quality. And the various supply houses use different part numbers for the same part a lot. The two numbers to watch are 12717600 and 14717600. One of them is shorter and was originally what was used on the distributor caps on loopframes. The other starts showing up on the spark plug wires on T3's, in the parts books at least. Sometimes, they are hard as rocks. Some of them show up with wrong diameters. Big hassles. Gooping them up with RTV is no doubt a good thing, as you never know what you're going to get.

TdF

[John A]

If I want a reliable light, I use a decent generic oil pressure switch. The last one I used one from a 82 Dodge slant six because I had one. As I remember its closing pressure was about the same as the Guzzi switch. The thread is 1/8 pipe so I used an adapter from a Steward Warner generic installation kit. ‘Snot like the old days when you had to make your own adapter.

[bigbikerrick]

The NAPA Echlin OP- 6065 looks like its substantially built, and should be a direct fit for our Guzzis. Not bad for $15.99  I  also thought about mounting an oil pressure gauge, at one time, but then I would also want a pressure gauge to monitor the pressure of the ATF circuit.....Its a slippery slope, fellas !
Rick

[John A]

A slippery slope indeed! I quit using gauges on motorcycles unless I was troubleshooting because I found I was paying too much attention to them. A voltmeter is all I generally have and I like a reliable light for oil pressure . I think it should be labeled “replace bearings “ . I can see how a Convert could send you down that slippery slope with transmission monitoring.