Jump to content

Bmc 1.5 Oil Pressure Sender Unit


Darren72

Featured Posts

Our presure guage is off the scale. The sender unit has a bad connection, its been sending odd readings for a while. If I change the unit do I need to pair it with the guage. How big/small a job is the unit.?

Link to comment
Share on other sites

Our presure guage is off the scale. The sender unit has a bad connection, its been sending odd readings for a while. If I change the unit do I need to pair it with the guage. How big/small a job is the unit.?

 

Yes. First of all you need to establish whether your guage is US or European standard (Euro are calibrated in bars, US are calibrated in PSI) then you need to identifty the pressure range, and finally you need to identify the screw thread of the unit.

 

ASAP stock dozens of different senders here :- http://www.asap-supplies.com/marine/ Type "oil pressure sender" into the search box to see them all. Your best bet is to give them a call, with details of your engine and the guage, they should then be able to advise the appropriate unit. I have always found them to be very helpful.

 

Changing the unit is a simple job, it just needs an open ended spanner of the correct size. Don't do it with the engine running !!!!

Edited by David Schweizer
Link to comment
Share on other sites

They do need to be paired to the gauge.

I would replace it with a mechanical one, more accurate and reliable

Whilst your at it add a buzzer along with a warning light, I did and it saved my engine when an oil pipe fractured

 

and there is the reason I would always use a modern electrical setup. The senders may weep but I have never known one leak enough to bring the oil warning lamp on.

Link to comment
Share on other sites

Yes. First of all you need to establish whether your guage is US or European standard (Euro are calibrated in bars, US are calibrated in PSI) then you need to identifty the pressure range, and finally you need to identify the screw thread of the unit.

 

ASAP stock dozens of different senders here :- http://www.asap-supplies.com/marine/ Type "oil pressure sender" into the search box to see them all. Your best bet is to give them a call, with details of your engine and the guage, they should then be able to advise the appropriate unit. I have always found them to be very helpful.

 

Changing the unit is a simple job, it just needs an open ended spanner of the correct size. Don't do it with the engine running !!!!

 

Sorry to sound a numpty. Once I have the old one in hand what am I looking at to find the screw thread. Most are 1/8 aint they? My existing guage shows PSI and bars.

They do need to be paired to the gauge.

I would replace it with a mechanical one, more accurate and reliable

Whilst your at it add a buzzer along with a warning light, I did and it saved my engine when an oil pipe fractured

We do have a warning light already. You mentioned a mechanical one!? Edited by Darren72
Link to comment
Share on other sites

You mentioned a mechanical one!?

One of two types of oil pressure gauge will be fitted, electrical or mechanical. Electrical will have a sensor, with wires running from the sensor to the gauge with the pressure measured at the sensor, mechanical will have a small bore pipe running from the engine to the gauge so that the oil pressure is measured at the gauge itself.

Link to comment
Share on other sites

Sorry to sound a numpty. Once I have the old one in hand what am I looking at to find the screw thread. Most are 1/8 aint they? My existing guage shows PSI and bars.

We do have a warning light already. You mentioned a mechanical one!?

 

Yes it will be 1/8" NPTF (National pipe Thread - Fine( (27 tpi) if it is an electrical sender. but if it is a capiliary unit, it could also be 1/8" BSP (British Standard Pipe thread) which is a slightly smaller diameter with 28 tpi.

 

Most gauges show both PSI and bars , but one scale will be more dominant than the other, it is the dominant one which should be used to dertermine either Euro or US type. The examples shown below illustrate the difference -

 

FAR12926.jpgFAR15103.jpg

 

Euro Resistance (bar) US Resistance (PSI)

Edited by David Schweizer
Link to comment
Share on other sites

Yes it will be 1/8" NPTF (National pipe Thread - Fine( (27 tpi) if it is an electrical sender. but if it is a capiliary unit, it could also be 1/8" BSP (British Standard Pipe thread) which is a slightly smaller diameter with 28 tpi.

 

Most gauges show both PSI and bars , but one scale will be more dominant than the other, it is the dominant one which should be used to dertermine either Euro or US type. The examples shown below illustrate the difference -

 

FAR12926.jpgFAR15103.jpg

 

Euro Resistance (bar) US Resistance (PSI)

 

 

 

Thanks Dave.

Link to comment
Share on other sites

I have hopefully attached photos of my guage and sender. The PSI and BARS, neither readings look more prominate than the other. Which would you say it is. BARS because its the top reading??post-13179-0-97117100-1436038801_thumb.jpgpost-13179-0-42397200-1436038818_thumb.jpgpost-13179-0-14135900-1436038840_thumb.jpg

Link to comment
Share on other sites

I think its Kg/sq mm and PSI not Bar and PSI.

 

I have known euro gauges showing PSI and that gauge looks like an old one to me so likely to be a euro one.

 

A gauge that has lost its internal or external earth connection may also read maximum deflection. (Bi-coil gauges). I doubt yours uses a volatile stabiliser although it might on a BMC but not with that sender I feel.

 

Not much help I know. I would tend to replace as a pair using gauges that display units you are familiar with. The you know if its a US or Euro standard.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.