Oil Pressure gauge not working (1 Viewer)

[PaulGrant]

Hi Guys,

I have an oil pressure gauge that is not working. I have purchased a new oil pressure sender and installed it. When I inserted the clip back onto the sender and tested it the gauge still did not work. I also checked all my fuses.

I then noticed another clip on the same cable that connected to the sender. In all my wisdom I decided to connect this clip instead to check if it works. When I started the motor the oil pressure gauge appeared to work just fine.

I went for a quick drive and noticed 'steam/mist' behind my console glass. I shut the engine down.

I now appear to have burnt out the coil or something behind the instrument cluster. Could kick my own backside.

What is that other clip and why is is not connected. Also why does my pressure gauge not work? (before I munted it)

What is the best aftermarket pressure gauge I can get for my cruiser?
Where will I be able to get a new instrument console?

 

[ToyotaMatt]

Hi Guys,

I have an oil pressure gauge that is not working. I have purchased a new oil pressure sender and installed it. When I inserted the clip back onto the sender and tested it the gauge still did not work. I also checked all my fuses.

I then noticed another clip on the same cable that connected to the sender. In all my wisdom I decided to connect this clip instead to check if it works. When I started the motor the oil pressure gauge appeared to work just fine.

I went for a quick drive and noticed 'steam/mist' behind my console glass. I shut the engine down.

I now appear to have burnt out the coil or something behind the instrument cluster. Could kick my own backside.

What is that other clip and why is is not connected. Also why does my pressure gauge not work? (before I munted it)

What is the best aftermarket pressure gauge I can get for my cruiser?
Where will I be able to get a new instrument console?

View attachment 1661242

- Your Oil Pressure Sending Unit has 2 Terminals , One is a .250 Flat Male , The other is a .250 Insulated Brass Button Terminal

- Your .250 male spade is a Ground point where your wire harness feeds or delivers a solid steady good sensor - negative - power to

- The .250 Brass button Terminal is insulated on a thin carbon fiber circuit board material disc , this is where your wire harness connects to that sends a electrical signal back to the gauge in the dash

- The Grey .250 Connector is your ground wire and attaches to the male .250 spade terminal

- The black .250 connector has a Horse-Shoe or U shape cut out on one side , this slides over and snaps on the Brass insulated Button terminal

- It sounds like U attached your Black Connector / signal wire to your ground male .250 spade terminal ? With this particular YAZAKI Brand Connector it has a open face or end , and that is entirely possible , If U did for longer then a few seconds then a solid ground signal would have been sent to the gauge in the dash , spiking the gauge needle to full pressure , and ultimately / most likely burning up the gauge in the dash

- Hook up the connectors properly grey to the male spade , black horse-shoe to the brass button & see if the Gauge reads normal with engine running ?

- If the Gauge remains at FULL blast High or does not move at all , based on the smoke in your passenger cabin , then in all likelihood the OIL Gauge in the dash is Fried / Meltdown

- Is Your truck a 12v or 24v ?



Any one have Thoughts ?

 

[Dprio34]

Matt great analysis!
I didn't have any smoke, since that probably happened on the POs watch.
First I bought the sender and that didn't work. Then I took my gauge out and it looked like this.
Weird it was stamped with 24volts and I have a 12 volt system.
The windings that measure the resistance were all un-wound. And the pointer was spiked.

If you look closely you see where there was melting at the top, right behind the gauge face.

12V LJ70 with Oil Pressure Gauge stamped 24V. Not sure if it is max voltage or wrong gauge? Mystery.

 

[joekatana]

I have complete 12V gauge clusters available or even just the oil press gauge if you want

 

[Dprio34]

Joe, Can you PM me your info.
Thanks!!

 

[SNLC]

Just another suggestion while you are at it.

Clean out the oil relief valves and the oil check valve. Seems to be something neglected on the 70-series diesels that should be done every 100k or whatever.

Cheers

 

[ToyotaMatt]

Matt great analysis!
I didn't have any smoke, since that probably happened on the POs watch.
First I bought the sender and that didn't work. Then I took my gauge out and it looked like this.
Weird it was stamped with 24volts and I have a 12 volt system.
The windings that measure the resistance were all un-wound. And the pointer was spiked.

View attachment 1661448
If you look closely you see where there was melting at the top, right behind the gauge face.
View attachment 1661449
12V LJ70 with Oil Pressure Gauge stamped 24V. Not sure if it is max voltage or wrong gauge? Mystery.
View attachment 1661450

Wow ,

It looks like your gauge has seen Negative Ground for too long as well

was this a intentional grounding ( Mistake By the PO ) of the Primary Brass button Oil Sender Horse-Shoe Connector ,
or
a short to ground such as a break in the wire & rubbing at the firewall through hole rubber grommet location metal ground to earth scenario ?

I have seen more then one Toyota part stamped 24v and be used on a 12v system , Such as the hazzard switch on a 78-84 FJ40
USA spec. all have 24v stamped on them



If anyone knows why Toyota Stamps 24v on 12V vehical parts Please share the reasoning behind this ?

 

[Dprio34]

Thanks again for that insight Matt!!
Appreciate it!

Don

 

[Lomoski]

Just another suggestion while you are at it.

Clean out the oil relief valves and the oil check valve. Seems to be something neglected on the 70-series diesels that should be done every 100k or whatever.

Cheers

Where are these located?

 

[Dprio34]

Behind the oil filter.

 

[SNLC]

Where are these located?

There is also one here.

Cheers

 

[Dprio34]

Ian, I'm not sure about the KZ Engines, but on the L Engines, I don't believe there is a valve there as pictured above on the oil pump / timing cover assembly. Just an access port. ( Perhaps to assist priming a new oil pump?? )

 

[SNLC]

Ian, I'm not sure about the KZ Engines, but on the L Engines, I don't believe there is a valve there as pictured above on the oil pump / timing cover assembly. Just an access port. ( Perhaps to assist priming a new oil pump?? )

Ya, the manual the picture is from is for the 1HZ/1HDT/1PZ.

Cheers

 

[Dprio34]

Definitely not breaking stones here, just trying to learn something. I doubled checked my 2LT Engine Service Manual and it isn't indicated, and I went out to my old 2LT motor and there wasn't any valve in there either. Went to double check my newer 2LTII motor and the alternator is in the way to get an Allen in there. (not removing that today out of curiosity). But I am curious why the port is even there if not to house a valve as such.

 

[PaulGrant]

- Your Oil Pressure Sending Unit has 2 Terminals , One is a .250 Flat Male , The other is a .250 Insulated Brass Button Terminal

- Your .250 male spade is a Ground point where your wire harness feeds or delivers a solid steady good sensor - negative - power to

- The .250 Brass button Terminal is insulated on a thin carbon fiber circuit board material disc , this is where your wire harness connects to that sends a electrical signal back to the gauge in the dash

- The Grey .250 Connector is your ground wire and attaches to the male .250 spade terminal

- The black .250 connector has a Horse-Shoe or U shape cut out on one side , this slides over and snaps on the Brass insulated Button terminal

- It sounds like U attached your Black Connector / signal wire to your ground male .250 spade terminal ? With this particular YAZAKI Brand Connector it has a open face or end , and that is entirely possible , If U did for longer then a few seconds then a solid ground signal would have been sent to the gauge in the dash , spiking the gauge needle to full pressure , and ultimately / most likely burning up the gauge in the dash

- Hook up the connectors properly grey to the male spade , black horse-shoe to the brass button & see if the Gauge reads normal with engine running ?

- If the Gauge remains at FULL blast High or does not move at all , based on the smoke in your passenger cabin , then in all likelihood the OIL Gauge in the dash is Fried / Meltdown

- Is Your truck a 12v or 24v ?



Any one have Thoughts ?

Now that makes a lot of sense. Well the smoke did leave my dash gauge so it is FUBAR!

 

[PaulGrant]

Now that makes a lot of sense. Well the smoke did leave my dash gauge so it is FUBAR!

My truck is 24v

 

[PaulGrant]

Wow ,

It looks like your gauge has seen Negative Ground for too long as well

was this a intentional grounding ( Mistake By the PO ) of the Primary Brass button Oil Sender Horse-Shoe Connector ,
or
a short to ground such as a break in the wire & rubbing at the firewall through hole rubber grommet location metal ground to earth scenario ?

I have seen more then one Toyota part stamped 24v and be used on a 12v system , Such as the hazzard switch on a 78-84 FJ40
USA spec. all have 24v stamped on them



If anyone knows why Toyota Stamps 24v on 12V vehical parts Please share the reasoning behind this ?

No, mine was purely based on stupidity and laziness!

 

[PaulGrant]

I found a 24v oilpressure gauge on ebay Oem OYOTA OIL PRESSURE GAUGE, RECEIVER HZJ PZJ Land Cruiser 8324660060 | eBay

 

[ToyotaMatt]

I found a 24v oilpressure gauge on ebay Oem OYOTA OIL PRESSURE GAUGE, RECEIVER HZJ PZJ Land Cruiser 8324660060 | eBay

I have purchased from this seller K5Com on 2 separate occasions in the past , The package came from Japan & i thought the price was fair for what i was buying

considering both times were NOS parts

my feedback was positive each time

my 2 cents

 

[Dprio34]

Purchased and received a new Oil Pressure Gauge from @joekatana last week.
Can't wait to hook it up. Opened everything up today to inspect.
Yes, this gauge has 24volts stamped on it even though it is out of a 12 volt system.
Yes, that one also has a weird loop-d-loop wire wrapping around the pointer, as well too.
(looks like a hot mess) but exactly like the other one, without any associated melted plastic.

My Oil Pressure sender wires (ground) looks more like a ground strap than standard ground wire.
My Positive is Black with a red insulator. Easy to see how a lot of folks could mistakenly hook this black wire to the ground tab, thinking it was the ground, and fry the gauge.