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It can, and usually from collateral damage from the bad cylinders. Why? It's simple... When the cylinders and Pistons wear, microscopic debris is suspended in the oil from the wear metals of those components..
That oil is then fed into the lifters, and there's no way for the oil to make its way out of the lifter unless it bleeds by the hydraulic tip... Debris laden oil won't do that, the debris stays inside the lifter, and effectively seizes the hydraulic assembly.
This gives the lifter lash, and lash = noise.
No, the oil filter won't stop this; because, it sucks.
A leak down test won't show much, and often the BAD CYLINDER tests BETTER than the others. This is the case with both compression and leak down tests. Why?
Oil is what promotes cylinder/ ring sealing most. This issue almost always leads to some chamber contamination with engine oil. This helps to seal those rings up better..
You can learn more by looking at the exhaust bolts, or removing the header pipes and looking for oil. If you see this, then you have cylinders that have lost ring seal, and in some way have been compromised.
Oil can indeed improve cylinder/ring sealing in a compression or leak down test. The old trick of adding oil to the weakest cylinders to help determine if the low numbers were due to cylinder/ring sealing -- the oil improved this and the resulting numbers would go up -- or valve sealing comes to mind.
IIRC the oil jets only work at some relatively high oil pressure (above several bar if I care to trust my memory) and one wonders if the starter can crank the cold engine fast enough to generate enough oil pressure to even open those oil jets.
So there is the question of do the cylinders even receive any oil during this test.
Even if they do all cylinders receive the oil so it is relative.
In the case of this engine if bore scoring accounts for the noise the cylinder is pretty heavily scored so one could assume (sure risky) the benefit would be there but the cylinder would still come in weaker than the rest.
Granted, not 100% certain.
But compression and leak down tests are about all that are available to the DIY'er.
But I like the technique you use: That exhaust system pressure transducers to log and plot the pulses with the Bosch MTS5200 lab scope. Unfortunately that's not available to just the average DIY'er.
IIRC the oil jets only work at some relatively high oil pressure (above several bar if I care to trust my memory) and one wonders if the starter can crank the cold engine fast enough to generate enough oil pressure to even open those oil jets.
So there is the question of do the cylinders even receive any oil during this test.
Forget the oil squirters. The oil that lubricates the cylinders is waste oil from the rod bearings, delivered from the centrifugal force of the crankshaft into the cylinders.
The oil squirters work a little differently in practical application, break a case apart, else up some oil passages, install some fittings, and watch what happens with the oil squirters at different pressures, with different oil temperatures, and different viscosities. Want to get really interesting info? Do the same test with new oil, and used oil with different mileage.
See what the squirters do.... Try it.
Last edited by Flat6 Innovations; Oct 4, 2016 at 01:10 PM.
The oil squirters work a little differently in practical application, break a case apart, else up some oil passages, install some fittings, and watch what happens with the oil squirters at different pressures, with different oil temperatures, and different viscosities. Want to get really interesting info? Do the same test with new oil, and used oil with different mileage.
See what the squirters do.... Try it.
Have you tested how much airflow from the piston movement affects to the oil that is flown thru the squirters?
I havent, but your post got me thinking of it, becouse that testing procedure removes airflow from equation.
Have you tested how much airflow from the piston movement affects to the oil that is flown thru the squirters?
I havent, but your post got me thinking of it, becouse that testing procedure removes airflow from equation.
No, but it won't help anything, only hurt things..
Mine comes and goes. My indy said that he'd recommend switching from 0w40 to 10w50. I would assume a scored cylinder would make the noise on a constant basis.
Mine comes and goes. My indy said that he'd recommend switching from 0w40 to 10w50. I would assume a scored cylinder would make the noise on a constant basis.
A heavier viscosity oil can make a lifter issue worse, if that's what the problem is. Why? At start up the oil doesn't want to travel into the valve train components.
If I thought I had a bad lifter I'd add some Marvel Mystery Oil to the crankcase and see how it responded.
The noise coming and going doesn't rule out a cylinder, especially if temperature plays into things.
That's what i would have thought also. Will the noise come and go if it's a scored cylinder? The noise comes and goes in the cold and if it's warm.
I may have to try the mystery oil. Should i add it with the current oil, or with the next oil change?
Originally Posted by Flat6 Innovations
A heavier viscosity oil can make a lifter issue worse, if that's what the problem is. Why? At start up the oil doesn't want to travel into the valve train components.
If I thought I had a bad lifter I'd add some Marvel Mystery Oil to the crankcase and see how it responded.
The noise coming and going doesn't rule out a cylinder, especially if temperature plays into things.
Care package arrived from Pelican, pulled the oil filter and uggghhhhhhhhhhhh. Lots of sparkly bits. Some sort of film is in there too, the car had both head gaskets changed along with the heater core before I bought it.
Filter seems to have a lot of small metal particles. I have changed it, but this was supposedly changed along with oil at time of the head work, so not very old.
And no it's unfortunately not from the lawn mower.
Yeah, I'm planning on sump pan drop tomorrow. Not sure about ferrous v's non ferrous, they look like white metal in the oil, will go and clean it when I drop pan tomorrow. Some of it is plastic film (or something similar), that large bit on the RHS of the bowl is like that.
use a magnet to separate the debris.
I my case I had some minor plastic,minor ferrous and mainly non ferrous. Main bearing #5 ! Caused by a P.O schlocky IMSB replacement.
Thanks, will look I'm thinking I will try and filter the oil through a cloth or similar to screen out the suspended particles. What symptoms did you get with that bearing failure?
Ticking that I mistook for lifters !
After dismantling the engine for a rebuild, I found several 'bad' lifters also. It is theoretically possible(?) that the debris that took out the bearing and the bearing debris plugged the lifters but I saw no evidence of that. I just replaced everything anyway- $$$$, Totally upside down now.
