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When you look inside the engine block while running what should the inside look like?

V

vulvalover

New member
Joined
Sep 28, 2018
My oil sensor light is flickering. At first it was very faint and only did it a little bit and then would go away. A few days later it would come on flickering very fast, but much brighter. I drove it today with the oil light mostly on, flickering "violently", but staying strong non the less.

I took the oil cap off while the engine was running. I saw little droplets of oil kicking up from the crank shaft. It seemed to be lubricating the engine but... Well what is it suppose to look like? There was some oil kicking up but how much is enough? It was more of a vapor spray, smaller droplets, nothing really shot out of the engine block.

My dipstick has oil all across the small etched marker part. I was always told this was the "full" setting. But the manual states this represents 1 quart. Does that mean I should have a dipstick with 3-4 inches of oil going across it?

I added half a quart of oil the first time the oil warning light came on, it seemed to help for a few hours at least. I added another half a quart the next time the senor kicked on and it did diddly squat. The senor still flickering. I see no oil leaks underneath the oil pan or anything drops coming from underneath. I don't see any leaks on the engine either at least not at a quick glance.

It took this car a little while to start doing this since I got it. But I noticed when I got it, it had 4 quarts of oil sitting on the floor. I'm starting to think this issue may have happened previously before? But I got about 2-3 weeks of driving it before the oil sensor started doing this. Strange that it would go away for that long if this was a previous issue, no?

Anybody know what this is and why it's happening?
 
What car and year? You should have oil over half the etched part or more, but not above. I would look at the wire going to the sensor first. It starts on the passenger side front, towards the bottom of the block, then runs across the front of the block behind timing cover to loin the rest of the wires. The insulation may be gone, the connection bad, etc.
Also make sure you don't need an oil change, worn out oil lowers oil pressure. Usually that light wouldnt come on until you have almost no oil left in the motor.
 
Also.. you were looking at the camshaft, not the crankshaft. Nothing should be shooting out of the oil cap. The cam has oiling holes lubricating it, oil isn't just shooting all over the place inside the engine. Idk why the trolls haven't lit you up yet, but be ready. The hash marks on the dipstick represent 1 quart from top to bottom. When you get to the bottom of the hash marks, add 1 quart.
 
2turbotoys said:
Idk why the trolls haven't lit you up yet, but be ready.
Click to expand...

LOL.

Removing the oil cap while the engine is running WILL result in oil being flung out the fill hole by the cam.

Nothing wrong with that... It's normal (well, as normal as it can be considering that it isn't normal to remove the cap while running ;-) )
 
Oh, and too much oil in the pan can cause oil aeration. Not to much effect in the b23 / b230 because of the baffle in the pan. Anyway, aeration is an easy way to kill an otherwise healthy engine.

Do not overfill.

And check the wiring. The low oil pressure light flickering is *usually* bad wiring.
 
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JohnMc said:
If the flickering doesn't get worse when the engine is warm and/or the revs are lower, it's more likely than not to be the wiring.
Click to expand...

Well of course there are several likely scenarios that would precipitate the flickering.

1. Damaged wiring
2. Bad oil pressure sender
3. Aerated oil / incorrect viscosity
4. Worn bearings
5. Contaminated oil pump pickup screen.
6. Damaged / worn oil pump
 
I was agreeing with your opinion. Most causes of actual low pressure will be more dependent on low revs and/or high temp.
 
just to complete that^^ list:
7. oil pump pick-up tube seals (partly)blown out.

but i would suspect the sensor wiring first
 
vulvalover said:
I drove it today with the oil light mostly on, flickering "violently"
Click to expand...
Excellent way to destroy your engine.

My dipstick has oil all across the small etched marker part.
Click to expand...
Checked with the engine *off*?
Pull out dipstick.
Wipe it clean.
Insert all the way. Pull it out again.
Look at dipstick, both sides.
There should be a *solid* covering of oil in the crosshatch area. Preferably at the top of it. Not below.

I added half a quart of oil the first time the oil warning light came on, it seemed to help for a few hours at least. I added another half a quart the next time the senor kicked on and it did diddly squat. The senor still flickering.
Click to expand...
The oil light is NOT a level sensor. It's a pressure sensor. It's telling you there is no oil pressure, and your engine is getting no lubrication. Try going down a water slide with the water turned off. What happens to your butt is what's happening to your engine's bearings.

But I noticed when I got it, it had 4 quarts of oil sitting on the floor.
Click to expand...
Previous owner had a problem and knew about it.

If it isn't leaking, it may be burning it. Any clouds of smoke from the tailpipe?
Valve seals can leak, allowing oil to be sucked past them and into the cylinders, where it gets burned along with the gas/air mixture. Worn piston rings can do the same thing.

FYI, here's a generic picture of a dipstick. From left to right:

OMG .......... Add a quart .......... Okay .......... Perfect! .......... Oops, a bit high.


<img src="https://cdn3.vectorstock.com/i/1000x1000/48/27/oil-dipstick-vector-21314827.jpg" width=700 height =400></a>
 
If the insulation on the wiring is good and a new sender doesn't fix the flickering light (they do fail occasionally), you're probably looking at pulling the oil pan to replace the blown out oil tube seals.

OilDeliveryTubeORing.gif


If that's the case be sure to use original Volvo seals. They're made of better material than the aftermarket seals.

If you have access to a mechanical pressure gauge connect it to the oil sender port and see if the pressure is actually low before pulling the pan.
 
hiperfauto said:
If the insulation on the wiring is good and a new sender doesn't fix the flickering light (they do fail occasionally), you're probably looking at pulling the oil pan to replace the blown out oil tube seals.

OilDeliveryTubeORing.gif


If that's the case be sure to use original Volvo seals. They're made of better material than the aftermarket seals.

If you have access to a mechanical pressure gauge connect it to the oil sender port and see if the pressure is actually low before pulling the pan.
Click to expand...

That pic looked so familiar: http://cleanflametrap.com/oilpan/ :cool:

When my daughter's '91 started lighting up the oil light in a flicker, and not when she went around a ramp fast, I was reminded of that picture, and that oil pan. When she got it to me, I thought I'd check the pressure as you advise, with the idea in the back of my mind that spark plugs were M14 thread, so I could maybe use an old compression gauge I'd replaced. Whoops, wrong thread pitch. So, without any better idea, I swapped in a spare sender. Light was gone. Whew!

Did a full necropsy on the old sender to learn what happens to them. The sender failed by developing a slow leak (nothing obvious about it under her 335K mile hood) so the pressure needed to keep the switch open gradually rose with the worsening leak. Glad it was a $7 problem, and one so quickly taken care of. Gave me a reason to order the proper fitting for a test gauge.
 
Excellent advice

Awesome advice from everyone thanks.

That's essentially what I just came across online -
https://www.justanswer.com/volvo/1b9as-1991-volvo-740-oil-pressure-light-on-restart-knocking.html

The guy said his problem was a broken timing belt and had nothing to do with the oil, but otherwise the mechanics response sounds tailored to my set of particular problems with the oil. My car has shut off several times while driving it, but then turns right back over if I turn it completely off then on again. Sounds like my sensor is going wonky.

This sounds like my problem again except I've had no maintenance done to my head gasket or camshaft oil seals that I'm aware of -
https://www.matthewsvolvosite.com/forums/viewtopic.php?t=42014

This part sounded most interesting -
"There is a relief valve spring in the oil pump. If this is sticking the same symptom can occur. "

This also might explain my errant oil sensor light, although it's much more full on flickering now then faintly appearing for a while and going away. Still goes away for a bit though then comes back.

Would also explain that why my car auto shuts off while driving.

Found some interesting links pertaining to the oil pump removal/replacement, though they could be better - http://www.volvotips.com/index.php/740-760-780/volvo-740-760-780-service-and-repair-manual/
http://www.volvotips.com/service-manual/volvo-740/Volvo-740-760-780-940-960-B204-B234-16valve-engine-service-manual.html
Page 60 describes how to take out and replace the oil pump. Hopefully it's just the sensor that I'm having problems with though.

So my first step is to check the wiring and sender, see if its loose or something. Replace the sender.

Second is
hiperfauto said:
If you have access to a mechanical pressure gauge connect it to the oil sender port and see if the pressure is actually low before pulling the pan.
Click to expand...
to test the oil pressure!

Looking for diagrams online to find where the oil sender/sensor unit is... Can anyone direct?
 
vulvalover said:
My car has shut off several times while driving it, but then turns right back over if I turn it completely off then on again. Sounds like my sensor is going wonky.
Click to expand...
Nope, the oil warning light coming on will not make the engine stop running.

Looking for diagrams online to find where the oil sender/sensor unit is... Can anyone direct?
Click to expand...
Generally right side of engine, down low at the front, in front of the oil filter. Between filter and alternator on 240s.

A couple of different styles:

OilPressureTestPort.gif


4819847854_32d5edd876_z.jpg
 
vulvalover said:
I drove it today with the oil light mostly on, flickering "violently", but staying strong non the less.
Click to expand...
Sounds like a wiring issue.

If the oil pressure is low, it usually comes on at idle when the engine is warmed up. On my car, it will come on if the engine is hot and I start braking and then clutch-in (neutral). The RPM drops and the light comes on. If you blip the throttle to raise the RPM, the light should go out.
 
Awesome responses thanks everyone. I'll post some pics later but long story short I bumped some of the crusty wires beneath/around the alternator with my hand and wiggled one that was grounding to the engine block. Oil pressure light was no longer lit, drove it several times and went on extended drive - no sudden turn offs or engine croaks while driving. Engine sounds good no creaks or squeaks due to no oil on the bearings. PHEW I hope that light never comes on again...!
 
2turbotoys said:
Idk why the trolls haven't lit you up yet, but be ready.
Click to expand...

:lol::rofl:

Not to be the newest alter boy on the Volvo block but I believe I have already been full blown initiated. But lord knows it's just a matter of time until it happens again. Maybe if I stop dressing-er... typing for it, it'll stop. :lol:
 
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