MEP803A no oil pressure after oil change.

[Medic1]

So thanks to the most recent hurricane we ran our MEP 803A for about 113 hours while waiting for power to come back. Now that the power is back on, we decided to service all the generators, just in case it goes back out and change the oil and the fuel filters on this machine change the engine oil start the machine back up now I have no oil pressure on the gauge, but the machine does not turn off and indicate low pressure. Anybody got any ideas and up till now the gauge has performed perfectly and it ran right at about 50 to 60 PSI the whole time we were running it. we have four of these units on the ranch that we used to power it during outages so we’re fairly familiar with them, but I’ve never run into this.

 

[WWRD99]

So thanks to the most recent hurricane we ran our MEP 803A for about 113 hours while waiting for power to come back. Now that the power is back on, we decided to service all the generators, just in case it goes back out and change the oil and the fuel filters on this machine change the engine oil start the machine back up now I have no oil pressure on the gauge, but the machine does not turn off and indicate low pressure. Anybody got any ideas and up till now the gauge has performed perfectly and it ran right at about 50 to 60 PSI the whole time we were running it. we have four of these units on the ranch that we used to power it during outages so we’re fairly familiar with them, but I’ve never run into this.

If I remember right there's 2 sensors for oil pressure. 1 for the genset and one for the gauge. Any chance you bumped the wire when changing the fuel filter? I think that one is right there with the filters.

Sent from my SM-S906U using Tapatalk

 

[Medic1]

If I remember right there's 2 sensors for oil pressure. 1 for the genset and one for the gauge. Any chance you bumped the wire when changing the fuel filter? I think that one is right there with the filters.

Sent from my SM-S906U using Tapatalk

Thank you, I will check.

 

[DieselAddict]

The shutdown signal comes from a switch that is separate from the sending unit that powers the gauge.

Have you done the easy thing and check the wire to make sure its not broken or knocked off from changing the filter?

I have had the wire break in the crimp. The wire looked OK but wasn't actually connected.

 

[DieselAddict]

If I remember right there's 2 sensors for oil pressure. 1 for the genset and one for the gauge. Any chance you bumped the wire when changing the fuel filter? I think that one is right there with the filters.

Sent from my SM-S906U using Tapatalk

We were thinking the same thing at the same time!

 

[WWRD99]

We were thinking the same thing at the same time!

I have no idea how I remember that but forget where my glasses are. I hope that's what's wrong with it. I know I've gotten a little crazy getting that fuel filter off!

Sent from my SM-S906U using Tapatalk

 

[spotrep]

Welcome to the forum! Im happy to hear that yall came out safely and that power is returned.

a few things:
1. many suggest adding a mechanical Oil pressure gauge.

To do so you will need a brass tee: https://www.amazon.com/gp/product/B0B9M4HKMT/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8

and a gauge: https://www.amazon.com/Marshall-Instruments-CW00060-Pressure-Gauge/dp/B00TYY3SRA/ref=sr_1_13?sr=8-13

If you ever have any part of OP system failure you always have mechanical backup this way.



2. Youre on the right path with info others have given for now. If you dont find the issue there next step is TM's.
To get you started on troubleshooting from the TM:

TM 9-6115-642-24

LOW OIL PRESSURE
Step 1. Check for improper lubrication oil.
a. If proper lubrication oil, do Step 2.
b. If improper, drain oil and refill with proper lubrication oil (TABLE 2–3), Replace oil filter in accordance
with TM 9-2815-253-24.
Step 2. Test for defective OIL PRESSURE indicator, paragraph 2-41.2.
a. If OIL PRESSURE indicator is not defective, do Step 3.
b. If defective, replace OIL PRESSURE indicator, paragraph 2-41.
Step 3. Test for defective oil pressure sender, paragraph 2-91.1.
a. If defective, replace oil pressure sender, paragraph 2-91. ./
b. If oil pressure sender is not defective and trouble persists, notify next higher level of maintenance.

 

[Jeepadict]

Welcome to the forum! Im happy to hear that yall came out safely and that power is returned.

a few things:
1. many suggest adding a mechanical Oil pressure gauge.

To do so you will need a brass tee: https://www.amazon.com/gp/product/B0B9M4HKMT/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8

and a gauge: https://www.amazon.com/Marshall-Instruments-CW00060-Pressure-Gauge/dp/B00TYY3SRA/ref=sr_1_13?sr=8-13

If you ever have any part of OP system failure you always have mechanical backup this way.

View attachment 932772

2. Youre on the right path with info others have given for now. If you dont find the issue there next step is TM's.
To get you started on troubleshooting from the TM:

TM 9-6115-642-24

LOW OIL PRESSURE
Step 1. Check for improper lubrication oil.
a. If proper lubrication oil, do Step 2.
b. If improper, drain oil and refill with proper lubrication oil (TABLE 2–3), Replace oil filter in accordance
with TM 9-2815-253-24.
Step 2. Test for defective OIL PRESSURE indicator, paragraph 2-41.2.
a. If OIL PRESSURE indicator is not defective, do Step 3.
b. If defective, replace OIL PRESSURE indicator, paragraph 2-41.
Step 3. Test for defective oil pressure sender, paragraph 2-91.1.
a. If defective, replace oil pressure sender, paragraph 2-91. ./
b. If oil pressure sender is not defective and trouble persists, notify next higher level of maintenance.

I dig adding the mechanical gauge, and that's a sweet spot for it. Thanks for the parts links, I added them to my cart. Nicely done!

Sent from my SM-G970U using Tapatalk

 

[spotrep]

I dig adding the mechanical gauge, and that's a sweet spot for it. Thanks for the parts links, I added them to my cart. Nicely done!

Sent from my SM-G970U using Tapatalk

I wish i could take credit for this. The credit belongs to others on the forum. I tried to search the threads where I came across it, but I couldnt find it. Be aware that you have options for the Pressure range. I purchased a 0-60 psi gauge, but they have 0-100 psi as well. I went with the 60 because I feel its gives me a better resolution and I dont anticipate <60psi for my particular unit.

 

[Jeepadict]

I've been bangin' around this forum for a couple few years now and haven't come across it...never even considered it needing to be a thing. Thanks for keeping the idea alive!

 

[Medic1]

Thank you all I have checked wiring all looks good, now to go the the TM troublshooting. these were a great investment for sure. We have 4 803a's, an 802A and a 1060 we just picked up.

 

[spotrep]

Thank you all I have checked wiring all looks good, now to go the the TM troublshooting. these were a great investment for sure. We have 4 803a's, an 802A and a 1060 we just picked up.

dang buddy save some for the rest of us!!

 

[Guyfang]

You wrote:
The shutdown signal comes from a switch, (OP, or a so called LOP. Low Oil Pressure switch) that is separate from the ( MT7, Oil Pressure) sending unit, that powers the, (M7) gauge.

Have you done the easy thing and check the wire to make sure its not broken or knocked off from changing the filter?

I have had the wire break in the crimp. The wire looked OK but wasn't actually connected.

Sometimes its better to use the military Noun Nomenclature to avoid confusion, and the oil pressure system is a place it happens often.

What kind of oil was in it before the change? What kind went back into the engine? Dont laugh, seen it happen before.

 

[Medic1]

Welcome to the forum! Im happy to hear that yall came out safely and that power is returned.

a few things:
1. many suggest adding a mechanical Oil pressure gauge.

To do so you will need a brass tee: https://www.amazon.com/gp/product/B0B9M4HKMT/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8

and a gauge: https://www.amazon.com/Marshall-Instruments-CW00060-Pressure-Gauge/dp/B00TYY3SRA/ref=sr_1_13?sr=8-13

If you ever have any part of OP system failure you always have mechanical backup this way.

View attachment 932772

2. Youre on the right path with info others have given for now. If you dont find the issue there next step is TM's.
To get you started on troubleshooting from the TM:

TM 9-6115-642-24

LOW OIL PRESSURE
Step 1. Check for improper lubrication oil.
a. If proper lubrication oil, do Step 2.
b. If improper, drain oil and refill with proper lubrication oil (TABLE 2–3), Replace oil filter in accordance
with TM 9-2815-253-24.
Step 2. Test for defective OIL PRESSURE indicator, paragraph 2-41.2.
a. If OIL PRESSURE indicator is not defective, do Step 3.
b. If defective, replace OIL PRESSURE indicator, paragraph 2-41.
Step 3. Test for defective oil pressure sender, paragraph 2-91.1.
a. If defective, replace oil pressure sender, paragraph 2-91. ./
b. If oil pressure sender is not defective and trouble persists, notify next higher level of maintenance.

 

[Medic1]

Welcome to the forum! Im happy to hear that yall came out safely and that power is returned.

a few things:
1. many suggest adding a mechanical Oil pressure gauge.

To do so you will need a brass tee: https://www.amazon.com/gp/product/B0B9M4HKMT/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8

and a gauge: https://www.amazon.com/Marshall-Instruments-CW00060-Pressure-Gauge/dp/B00TYY3SRA/ref=sr_1_13?sr=8-13

If you ever have any part of OP system failure you always have mechanical backup this way.

View attachment 932772

2. Youre on the right path with info others have given for now. If you dont find the issue there next step is TM's.
To get you started on troubleshooting from the TM:

TM 9-6115-642-24

LOW OIL PRESSURE
Step 1. Check for improper lubrication oil.
a. If proper lubrication oil, do Step 2.
b. If improper, drain oil and refill with proper lubrication oil (TABLE 2–3), Replace oil filter in accordance
with TM 9-2815-253-24.
Step 2. Test for defective OIL PRESSURE indicator, paragraph 2-41.2.
a. If OIL PRESSURE indicator is not defective, do Step 3.
b. If defective, replace OIL PRESSURE indicator, paragraph 2-41.
Step 3. Test for defective oil pressure sender, paragraph 2-91.1.
a. If defective, replace oil pressure sender, paragraph 2-91. ./
b. If oil pressure sender is not defective and trouble persists, notify next higher level of maintenance.

Update, so I tested the gauge per the TM and it failed. New gauge ordered, and we are adding the pressure gauge above the sender as well ( thanks for those part numbers! ).

 

[Medic1]

While I am here anybody got any tricks to getting the factory spin-on fuel water separator filter off. Those things I swear are torqued to 150 foot lbs and glued on. The replacements go on and off without an issue but a lot of unsavory language and time has been spent on that one filter.

 

[Toolslinger]

There are past posts on those... I'm still waiting to do mine, but I think I'm prepared (unit is down hard with electrical issues)... My uncle just gave me a Caterpillar strap wrench that they used to give to every new Cat owner that looks like it could get a grip on, and remove anything. There's plenty of chain wrenches and more drastic tools waiting in reserve...

 

[Light in the Dark]

While I am here anybody got any tricks to getting the factory spin-on fuel water separator filter off. Those things I swear are torqued to 150 foot lbs and glued on. The replacements go on and off without an issue but a lot of unsavory language and time has been spent on that one filter.

Take the roof off above the operator cube, then take the panel off to the side of the fuel seperator. Get a chain wrench high up, damn near where it seats on the base, and give it hell. Only surefire way I do it... the rest is a lesson in time wasting and anger. Appropriately oil the new sealing gasket on the replacement, and hand tighten as needed.