Slant 6 oil pressure woes…

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Idk man. It’s bigger than all the other ones that are “stock” according to all the parts stores.
Many filter makers started making their filters smaller to save money. Some only hold about 3/4 of a qt. Just like you used to get a pack of hotdogs that were 16 oz. Now they are 14 oz.
 
Many filter makers started making their filters smaller to save money. Some only hold about 3/4 of a qt. Just like you used to get a pack of hotdogs that were 16 oz. Now they are 14 oz.
Worse comes to worst I’ll drain a little oil out tomorrow. It’ll be fine. I think my dad and I are gonna put a new oil pump on it tomorrow.
 
That's a standard one quart filter.
Yeah Charlie pointed that out. I’ll probably drain some oil out tomorrow. My dad is gonna come help me out and I’m gonna drop the oil pan and see if the pickup screen is plugged up, and probably just replace the oil pump entirely while I’m down there. But since the pan has to come off I’m gonna drain the oil anyway so I’ll just put less in it when it all goes back together
 
Yeah Charlie pointed that out. I’ll probably drain some oil out tomorrow. My dad is gonna come help me out and I’m gonna drop the oil pan and see if the pickup screen is plugged up, and probably just replace the oil pump entirely while I’m down there.
It could be. That's a common problem. When I first got Vixen back in 2019, she took longer than I liked for her oil light to go out from startup. I verified it with a manual gauge and then yanked the engine out. There was about 1/2" or so of sludge in the bottom of the pan. I cleaned it up, cleaned up the pickup, replaced the rod and main bearings even though they were good. I just happened to have some. I also put a new timing set back in it and put it all back together. I still have that original engine against the wall in the shop. It had great oil pressure when I put it back together. It was getting pressure before, but it was restricted just enough that it delayed the oil light going out. I still think before you do anything, you should verify the oil pressure loss on a manual gauge. Then you won't just be guessing. I just hate guessing. lol
 
It could be. That's a common problem. When I first got Vixen back in 2019, she took longer than I liked for her oil light to go out from startup. I verified it with a manual gauge and then yanked the engine out. There was about 1/2" or so of sludge in the bottom of the pan. I cleaned it up, cleaned up the pickup, replaced the rod and main bearings even though they were good. I just happened to have some. I also put a new timing set back in it and put it all back together. I still have that original engine against the wall in the shop. It had great oil pressure when I put it back together. It was getting pressure before, but it was restricted just enough that it delayed the oil light going out. I still think before you do anything, you should verify the oil pressure loss on a manual gauge. Then you won't just be guessing. I just hate guessing. lol
Yeah. That’s fair. I’ll see if I can’t get my hands on my brother’s gauge before I do the pan. It’s just so frustrating. I’ve never had issues with the oiling system in the car. Never even had that light come on for a second until just a couple weeks ago. It could be the pickup. It could be the pump just finally giving out. It could be both at once. I don’t know. But I can tell you that the pump is about 10 years older than the mother, maybe 8-9. I don’t exactly remember. But I have a brand new one and I have some fiber gasket material and some right stuff and the memory of last time I made this exact gasket. It’s not fun to cut a gasket out with an xacto knife but it is what it is. The money I’ve already out into it the last couple weeks and the stress of my apartment manager freaking out about it sitting for any length of time or an oil leak is always weighing on me. And it sucks too cause right now I got perfect spring cruising weather and this is the time of year I like to daily this car. Did it last year no problem.
 
Yeah. That’s fair. I’ll see if I can’t get my hands on my brother’s gauge before I do the pan. It’s just so frustrating. I’ve never had issues with the oiling system in the car. Never even had that light come on for a second until just a couple weeks ago. It could be the pickup. It could be the pump just finally giving out. It could be both at once. I don’t know. But I can tell you that the pump is about 10 years older than the mother, maybe 8-9. I don’t exactly remember. But I have a brand new one and I have some fiber gasket material and some right stuff and the memory of last time I made this exact gasket. It’s not fun to cut a gasket out with an xacto knife but it is what it is. The money I’ve already out into it the last couple weeks and the stress of my apartment manager freaking out about it sitting for any length of time or an oil leak is always weighing on me. And it sucks too cause right now I got perfect spring cruising weather and this is the time of year I like to daily this car. Did it last year no problem.
I'll say this. I have never seen an oil pump just "give up" all on its own. I've seen some lock up because they sucked up something in the rotors, but I've never seen an oil pump go bad all by itself. Think about it. They stay lubed all their lives. Unless of course, one just runs slam dry and by then something else upstream will have given it up first. Put a new one on it if you feel the need, but I would only get a bonafide Melling. I also run the high pressure spring in mine, but that's personal preference. Don't let it get you down. Have fun with it. It's JUST a slant 6. It's not like it's some hermorphrodite new computerized POS.
 
I thought I posted this earlier.... not seeing it now.
I had a 64 225 and trans here recently, actually fired it up while sittin on the trailer. Didn't run it but a minute or 2 each time, feeding it by dribbling gas in the carb throat.
I split the trans and put the engine on the stand. I drained the oil, and what I got out was the consistency of gas and blacker than tar.
I then pulled the pan (glad I hadn't flipped the engine at this point) and it was full beyond the top of the pickup screen with a gray mayonnaise consistency, sludge. I had sold the pan,
(front sump 60s truck pan, first front sump I'd ever seen on a /6) so had to clean it up for shipping. At least for that purpose, I'm glad it cleaned up easy and wasn't baked on.... I actually traded pans with a guy just to have something to keep the motor sealed up.
I didn't notice any knocks, only that the oil sending unit had been oozing out the thin crap that drained out thru the plug the whole minute or so it ran each time. Oozed out right at the crimp between the metal and the plastic. Once I saw the true contents of the pan I was glad I didn't run it any more than I had.... I'd be willing to bet that motor didn't have much oil pressure..... I took off what I wanted, and sent the motor and trans down 2 different roads....
you may be dealing with the same issue within your pan.
 
Charrlie got to this first, but if seven quarts is "full", something has to be wrong. As others mentioned, full is five quarts unless you have some oddball racing hi-capacity pan. I'm guessing you either have the wrong dipstick or it's mismarked. To verify your dipstick is correct, drain the oil and put a new 1-qt filter on it like the WIX you were using. Add four quarts of oil and start the engine, letting it run for a minute or so then shut it off. Now the filter is full. Pull the dipstick and check it - you should be at the "add" mark. If not, make a mark for the new - and correct - "add" mark. Add one more quart of oil, you should be at the "full" mark. And again, if not make a new correct "full" mark.

All of this is assuming you don't have a huge buildup of crud in the pan, which would throw off your measurements. If you're going to pull the pan and check the pickup, the above should be done after that process.
 
Yeah. That’s fair. I’ll see if I can’t get my hands on my brother’s gauge before I do the pan. It’s just so frustrating. I’ve never had issues with the oiling system in the car. Never even had that light come on for a second until just a couple weeks ago. It could be the pickup. It could be the pump just finally giving out. It could be both at once. I don’t know. But I can tell you that the pump is about 10 years older than the mother, maybe 8-9. I don’t exactly remember. But I have a brand new one and I have some fiber gasket material and some right stuff and the memory of last time I made this exact gasket. It’s not fun to cut a gasket out with an xacto knife but it is what it is. The money I’ve already out into it the last couple weeks and the stress of my apartment manager freaking out about it sitting for any length of time or an oil leak is always weighing on me. And it sucks too cause right now I got perfect spring cruising weather and this is the time of year I like to daily this car. Did it last year no problem.
I was wondering if anybody had mentioned the pressure relief valve sticking, they do that, & can be serviced on the car.
 
have you verified that the wiring to the pressure sensor or the connection there isn't hanging on by a thread.

i'd be inspecting that before replacing oil pumps.

but before ANY of that i'd put a mechanical gauge on it to confirm pressures: cold, hot, idle, 2K and on a road test-- have a co-pilot watch the gauge while stopping/accel, etc.
 
have you verified that the wiring to the pressure sensor or the connection there isn't hanging on by a thread.

i'd be inspecting that before replacing oil pumps.

but before ANY of that i'd put a mechanical gauge on it to confirm pressures: cold, hot, idle, 2K and on a road test-- have a co-pilot watch the gauge while stopping/accel, etc.
Funny story… it turns out that I don’t have an oil pressure sending unit. At all. The wire that goes to it is cut and was dangling down against the greasy block. There’s a plug in the pump where the sending unit goes, and my ‘77 block doesn’t have a hole for the one that goes in the galley behind the pump like my old motor had.
 
Funny story… it turns out that I don’t have an oil pressure sending unit. At all. The wire that goes to it is cut and was dangling down against the greasy block. There’s a plug in the pump where the sending unit goes, and my ‘77 block doesn’t have a hole for the one that goes in the galley behind the pump like my old motor had.
interesting. so where were you getting the press reading for the dummy light?
 
interesting. so where were you getting the press reading for the dummy light?
I’m assuming that the “reading” I’m getting is just BS voltage fluctuations from being grounded to the block or just hanging loose or being grounded to the block but with grease between.
 
Not the best photo but I did this with a brass T to hook up my pressure light and have the mechanical gauge too.
Did this on a 64 Dart 225.

IMG_2006.jpg
 
there was
Funny story… it turns out that I don’t have an oil pressure sending unit. At all. The wire that goes to it is cut and was dangling down against the greasy block. There’s a plug in the pump where the sending unit goes, and my ‘77 block doesn’t have a hole for the one that goes in the galley behind the pump like my old motor had.
talk of a mechanical test gauge earlier. Then where would you even connect that? there should be a spot on the oil pump housing.
 
there was

talk of a mechanical test gauge earlier. Then where would you even connect that? there should be a spot on the oil pump housing.
see above ^^ T right off the housing to the dummy light press sensor and the tube for the mech. gauge.
 
there was

talk of a mechanical test gauge earlier. Then where would you even connect that? there should be a spot on the oil pump housing.
We decided to install the new pump with a mechanical gauge. Ran the hose through the hole in the firewall where the A/C drain hose would be if I had functional A/C. We’re averaging about 65lbs throughout the little cruise I just went on.
 
Having just read this entire thread late, box of popcorn in my hand and yelling at the screen, I have to make two observations:

1. Those requesting help from others on the internet will often become annoyed or insulted when those who are trying to help them (for Free) ask them very simple of basic questions.
In this particular case, the very simple "stupid" question would have been, "Is the oil light connected to anything?"
Sort of like the tech support guy on the phone asking, "Is the computer plugged in?"
"Of course it's plugged in! Do I look like an idiot?!?... Oh. Never mind. <Click> "
Even automotive service manuals advise that the mechanic "verify the customer's complaint" before proceeding.

Moral: Don't be insulted by questions that are "beneath your dignity," and don't be hesitant to ask them.

2. When you start a car with an OIL light, when you first turn on the switch, the light should go on.
Once the engine starts, the light should go off.
This is not an accident. It is a feature. If the wire is disconnected, or the bulb is burned out, the light will not go on, indicating a problem.
So you don't just watch to be sure the light doesn't turn on while you are driving – you watch to make sure it does go on when you start.
I feel confident that the OP's light did not go on when he turned the switch on.

As I say, just a couple of observations to cap an entirely amusing thread.

And, OP, why did you guys replace the oil pump after you found out the problem was the wire, rather than put a gauge on it, which is easier?

– Eric
 
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