Low Oil Pressure & High Temp Alarm

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woytovich

woytovich

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Seems like this would be a good belt & suspenders solution to avoiding chaos...
Oil/Temp Alarm

I would imagine one could add a delay relay to stop it from sounding the oil pressure alarm on start-up.

I know Longacre makes Oil pressure and Water temp warning lights with adjustable settings - could be wired to a buzzer in addition to the light. I like the adjustability but maybe just one more thing to fail?
GAGELITES

Thoughts?
 
This is what I use. It has a built in time delay on start up: ENGINE WATCHDOG Audible Engine Overheating Alarm, Gauge & Sensor

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That unit does not monitor coolant temperature, it relies on an external sensor. Where do you have the sensor located so that you are comfortable it is going to be accurate and would note overheating quickly enough?
 
woytovich said:
That unit does not monitor coolant temperature, it relies on an external sensor. Where do you have the sensor located so that you are comfortable it is going to be accurate and would note overheating quickly enough?
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The sensor can be mounted anywhere, but I have mine under the water discharge gooseneck stud. I have an Autometer gauge just down stream and the two gauges are within a few degrees of each other.

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I've always added an audible low oil pressure alarm to all my vehicles, which usually involved extending the oil pressure sender using braided cable and some type of multi-port connection block, like a multi-port airline block. Typically I used a 4# N.C. Hobbs switch, which unfortunately have gotten pretty pricy lately. When I decided to add another temperature sensor to monitor the head temps on my turbo'd 1HZ, I was pleased to discover the Engine Watchdog unit included an audible low pressure alarm built in. However, this time I decided to use a commonly available electric fuel pump pressure switch, which has both N.O. and N.C. contacts. It is much cheaper and available at any decent parts store.

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db3 said:
I've always added an audible low oil pressure alarm to all my vehicles, which usually involved extending the oil pressure sender using braided cable and some type of multi-port connection block, like a multi-port airline block. Typically I used a 4# N.C. Hobbs switch, which unfortunately have gotten pretty pricy lately. When I decided to add another temperature sensor to monitor the head temps on my turbo'd 1HZ, I was pleased to discover the Engine Watchdog unit included an audible low pressure alarm built in. However, this time I decided to use a commonly available electric fuel pump pressure switch, which has both N.O. and N.C. contacts. It is much cheaper and available at any decent parts store.

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Sounds all useful, but...I have no idea where to start on doing this on a 3FE. But I'll research it.

What psi is the low side for an alarm threshold? Or perhaps the way to ask is what is minimum operating oil pressure?
 
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LCnAZ said:
Sounds all useful, but...I have no idea where to start on doing this on a 3FE. But I'll research it.

What psi is the low side for an alarm threshold? Or perhaps the way to ask is what is minimum operating oil pressure?
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The installation is easy, and is not engine dependent. You need to somehow add a second port to where your existing oil pressure sender is mounted, either using a T fitting or relocating the sender using a piece of hose to the T, which is what I have always done. The pressure switch I use operates at 5 pounds: Amazon product ASIN B00029JC7G I typically have used a son-alert, but any 12 volt buzzer will work. Wire a switched ignition wire to the positive side of the buzzer, with the other buzzer connection going to the N.C. side of the pressure switch. The pressure switch common terminal is then grounded. When you startup, the buzzer will sound until you have #5 pressure; conversely if your oil pressure drops below 5 pounds, the buzzer will sound.
 
db3 said:
The installation is easy, and is not engine dependent. You need to somehow add a second port to where your existing oil pressure sender is mounted, either using a T fitting or relocating the sender using a piece of hose to the T, which is what I have always done. The pressure switch I use operates at 5 pounds: Amazon product ASIN B00029JC7G I typically have used a son-alert, but any 12 volt buzzer will work. Wire a switched ignition wire to the positive side of the buzzer, with the other buzzer connection going to the N.C. side of the pressure switch. The pressure switch common terminal is then grounded. When you startup, the buzzer will sound until you have #5 pressure; conversely if your oil pressure drops below 5 pounds, the buzzer will sound.
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Why did you choose to relocate the sender? There appears to be a fair amount of room down there.

What is the fitting size of the sender (so I get the right T or fitting for hose)?
 
LCnAZ said:
Why did you choose to relocate the sender? There appears to be a fair amount of room down there.

What is the fitting size of the sender (so I get the right T or fitting for hose)?
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Maybe you have enough room to install both sensors using a fitting like this:Amazon product ASIN B006PKKXM4 If not, I'd get a braided hose oil pressure gauge install kit from Summit. Everything is 1/8" NPT.
 
Just tap a 4lb Hobbs switch into the oil cooler bolt head. Wire it to ground relay so you don’t have +12v wiring running all over the place.
 
db3 said:
Maybe you have enough room to install both sensors using a fitting like this:Amazon product ASIN B006PKKXM4 If not, I'd get a braided hose oil pressure gauge install kit from Summit. Everything is 1/8" NPT.
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That's the direction I'm headed with a Hobbs 4psi sensor. I haven't decided on the alarm end....whether to go with the Engine Watchdog to be able to monitor transmission temps, too...or just go with a 90dB piezo alarm for oil pressure. I have an email to Engine Watchdog check on a couple of things. I've asked them where the transmission temp sensor would attach.
 
db3 said:
Maybe you have enough room to install both sensors using a fitting like this:Amazon product ASIN B006PKKXM4 If not, I'd get a braided hose oil pressure gauge install kit from Summit. Everything is 1/8" NPT.
Click to expand...

Well, I'm running into fitment troubles. The 1/8" NPT male end of that or other adapters will not fit in the OEM sender port on the oil filter block; it's a bit too large for the port. Also the OEM sender will thread into the female 1/8" NPT port, but way too loosely. The sender can actually be wiggled once threaded into it.

I have a feeling this a metric vs non-metric issue...so I'm back to the question of what is the true spec of the OEM sender (size and thread pitch)? To achieve my goals with this mod, I have to have a fitting adapter that is male to match the sender, and female 1/8"NPT. I then also need the opposite; an adapter that is male 1/8" NPT and OEM sender fit female.

Anybody have any idea where to find such adapters?

With regards to the other creative suggestions, I would like to not go that invasive or different from OEM, if possible. I'm far more comfortable sticking to solid metal fittings for such a critical component/system.
 
Shout out to @db3 for your tip on how you rigged your alarm system. :clap: My system is almost complete now. I used the Holley sender switch wired as you describe in posts #6 and #8. Today I got to ops test it. It works exactly as desired/designed. I will be describing in detail and with photos late this week on my build site. Builds - Sentimental Restoration of Family 1990 FJ62 - https://forum.ih8mud.com/threads/sentimental-restoration-of-family-1990-fj62.1095049/page-10#post-14117714 We are waiting on Toyota to deliver a new OEM oil pressure gauge sender. The original fell apart on removal.
 
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LCnAZ said:
Shout out to @db3 for your tip on how you rigged your alarm system. :clap: My system is almost complete now. I used the Holley sender switch wired as you describe in posts #6 and #8. Today I got to ops test it. It works exactly as desired/designed. I will be describing in detail and with photos late this week on my build site. Builds - Sentimental Restoration of Family 1990 FJ62 - https://forum.ih8mud.com/threads/sentimental-restoration-of-family-1990-fj62.1095049/page-10#post-14117714 We are waiting on Toyota to deliver a new OEM oil pressure gauge sender. The original fell apart on removal.
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Project complete. You can check it out here. Builds - Sentimental Restoration of Family 1990 FJ62 - https://forum.ih8mud.com/threads/sentimental-restoration-of-family-1990-fj62.1095049/page-10#post-14126142
 
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