Oil Pressure?

[DCatSea]

Can someone tell me what is meant by "good oil pressure" on a 4D61 at different revs?

We went out for a half-day run today, and I thought that my OP looked "different". I have deliberately not mentioned numbers. Engine was running well at cruising, trolling and at high revs; no smoke or weird noises and no alarms. Mazboot was running like a little train, so I hope its just me being paranoid as the season runs down to the lay-up.

I'm going to be changing oil and filters next week anyway, and maybe this will "normalize" things.

Thanks to the AOG brains trust.

[boater_mike]

I try to run at least once a week. If I recall, mine is running about 40-50 psi. Maybe a little higher if I have more oil since there is about 1/2 quart variation from the low and high marks on the dipstick. All that being said, with a 35 year old pressure gauge, I'm not even sure of the actual oil pressure measurement. It swings up when the engine is started - which is always a good thing.

-Mike

[Beta Don]

Cars pretty much did away with actual oil pressure gauges many years ago largely because so many of us 'old timers' thought we knew what pressure was good for the engine and the dealers and manufacturers were getting too many complaints about perfectly normal readings. Some cars kept the gauge and just eliminated the numbers on it

Pressure will vary due to temperature, RPM, the brand and weight of oil you're using and how clean or dirty the oil and filter are

My opinion, for an old low RPM diesel engine is . . . . if it jumps up off the peg when you start it and then increases a bit between idle and higher RPM's, then you're good - Just pretend the numbers aren't there and remember those numbers are associated with a 35 year old gauge and a sender of questionable condition

Don

[WillieC]

I think the best part is noticing something "different". When equipped with idiot lights, the initial check is Key On, all lights should illuminate. At engine start, as OP rises and amps come up, etc..lights go out. That feature is simply "light bulb test" (and circuit wiring test and switch test...)
As for gauges, they are often merely indicators, so seeing a difference from what used to be may be telling you something. Trouble is, change often happens so slowly, and memory fades, at least for some of us, things can sneak up. For example, it took me several months to notice the little circle with the lower case "i" way up at the top of this screen.
Then there is the problem of gauge calibration...you regularly send yours in for recalibration, right? Me neither. And age of systems. Is the oil pressure actually dropping, or is the sender or gauge showing their ages? Am I standing in the same place the last time I looked at the gauge (parallax issue)? All this compared with what the book says for normal range.

Long silly answer for a simple question, sorry. I thought the original engine that came with the WillieC showed decent enough oil pressure, low at idle, higher when operating, with slight drop over hours of use. Then when I swapped engines, choosing the better condition oil pump and replacing the rod bearings, my oil pressure is way different in a good way. Still, the gauge is merely an indicator. Hopefully this new normal imprints itself on my fading brain cells so I notice negative deviations. But I have a long way to go to get down to where the old engine was still running fine. It's when you no longer trust the dependability that things get dicey.

[kerrye]

I generally look for difference between cold/hot and idle/high rpm's. I suspected something changed I would put a mechanical oil pressure gauge in the system and monitor it for a period of time to see what's happening. As a general rule I'd want to see 40+ pounds at speed and 10+ lbs at hot idle.

[DCatSea]

Thanks Albineers - great answers that have actually put my mind at rest. I'm running at around 40 - 50 so it must be me. Obviously I will now be keeping a paranoid's eye on the gauge, listening very carefully for alien noises, taking my pulse and heartrate, and generally reporting anything suspicious.

Incidentally - what little circled "i" at the ttop of the page; i don't have one - and now I'm frightened.

[Beta Don]

Good luck!!

A 4D61 is a combination of nearly every 'alien noise' generated by any mechanical contraption ever built!!

Still, once you get used to all 15 or 20 of them singing in unison, I suppose a trained ear could tell if one was missing or a new one was added

Don

[DCatSea]

It's a symphony.

[WillieC]

Albin not secure.jpg

The symbol on the left at the top of your computer screen...unless you are on a cellphone, maybe. I found out it means we're not quite secure, but I figured that out a long time ago.

Oh, sounds like you have quite the symphony going on as we do. It always takes me about fifteen or twenty minutes before my pulse comes down and my tinnitus kicks up and drowns it all out. Then I'm good. But I do watch the gauges.

[DCatSea]

I first "went online" with a Compaq PC (1989??) and I have just seen the "i" symbol for the first time - we live and learn. Anyway - there's nothing wrong with insecurity that can't be cured by good Scotch. I too watch the gauges.

Ah! The Mighty Lehman - Will Still be Running When the Last Cockroach Dies.