Oil change Needed

Marin said:

Ignorance is bliss isn't it Mr. Bill.

My UK acquaintances do not think the Dorset is a "delicate little flower" (another amateur-hour absurdity) but they know damn well what its weak points are and how to avoid provoking them.

Most of these guys have forgotten more about diesel engines--- particularly that generation of engines--- than the people who profess expertise on them here will ever know. Which is why I give pretty much zero credibility on stuff that actually matters to internet forums full of self-proclaimed experts and strongly advise others to seek out information from people whose credibility they can judge for themselves, preferably in person.

Forums like this are good fun, but when anyone here says on a clear day the sky is blue, look up first before you buy into their "advice."

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One "expert" you might want to discuss this with is Tony Athens on boatdiesel.com or he can be contacted directly by going to his web site: sbmar.com and getting his phone number.

"Also many stationary stand by generators are run/cycled on timers, weekly/monthly spool right up to 1800 from cold"

About bout all that can be done with unattended engines.

Sure they last for decades , but the total hours till removal is minor.

The big boys on cruise ships ,where there may be a dozen generating units that need to be switched in as house and propulsion loads vary ,use plumbing that keeps the off duty engines coolant up to temperature , so they can be switched on and share the loads almost instantly.

UPS , Fed EX and the rest shut down because of idle time rules from the Air Police ,.

Homework assignment

Some confusion in the thread. Long term storage, cold and warm starts are not equal. Problem is that unless you routinely dissect your engine in a lab, you will never know how much actual wear that your practices cause.

Time for a little homework:
www.bobistheoilguy.com/

I have rebuilt hundreds of marine diesels, and out of all of those rarely seen a case of worn bearings. Bearings damaged from corrosion, fuel dilution, running out of oil- plenty of those. But wear? Almost never seen. Most engines that come apart the bearings are in good shape, and often go back in.

And an engine that has been sitting for months still has bearings wet with oil. They do not "dry out". Some oil always there as a film, otherwise I would not have to wipe my hands when handling the shells, and I do!! Just a thin film is needed to protect on startup, and it is there.

The engines I rebuilt were due mostly from water getting in, overheating, running out of oil, or oil diluted with fuel. High hp engines run hard have other reasons, but that does not really apply to trawlers.

Don't worry about the bearings.

Just a addon.

If you run the engine to temp to warm up the oil. Be sure to pull the dip stick and test the oils temp on it. You'll find the oil temp rise lags well behind the coolants.

Good point what barnicles. Most think their engine is warm w the coolant is but it's not.

Just for relative input I worked in a diesel electric powerhouse in Alaska and we pre-heated the lube oil and coolant for 24hours prior to startup. Was 300 gallons of oil and ? Coolant on the most used engine. We re-refined the lube oil on site and reclamed about 70%. Can't remember why but the engineer said the re-refined oil was more desirable/better that new oil never used. We used 30wt Delo.

Yes I am an aviator, but radial engines were WAY before my time. I do remember though, that the engineer would "count the blades" as in so many rotations before the mags (ignition) were turned on. This WAS to get the oil flowing.

On turbine engines (as in today) we call rotation up to a certain rpm and oil pressure before adding fuel, but that has more to do with the fact that it otherwise would turn into a bonfire.

Ski in NC said:

I have rebuilt hundreds of marine diesels, and out of all of those rarely seen a case of worn bearings. Bearings damaged from corrosion, fuel dilution, running out of oil- plenty of those. But wear? Almost never seen. Most engines that come apart the bearings are in good shape, and often go back in.

And an engine that has been sitting for months still has bearings wet with oil. They do not "dry out". Some oil always there as a film, otherwise I would not have to wipe my hands when handling the shells, and I do!! Just a thin film is needed to protect on startup, and it is there.

The engines I rebuilt were due mostly from water getting in, overheating, running out of oil, or oil diluted with fuel. High hp engines run hard have other reasons, but that does not really apply to trawlers.

Don't worry about the bearings.

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Good points. How about cylinder walls and valve train?

oscar said:

Yes I am an aviator, but radial engines were WAY before my time. I do remember though, that the engineer would "count the blades" as in so many rotations before the mags (ignition) were turned on. This WAS to get the oil flowing.

On turbine engines (as in today) we call rotation up to a certain rpm and oil pressure before adding fuel, but that has more to do with the fact that it otherwise would turn into a bonfire.

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I once had a World War 2 naval mechanic tell me that the reason propellers were turned by hand before the engine was started was to pump oil that had accumulated in the bottom cylinders enough of which that hydro-loc might occur and wreck an engine if it had been started without doing so. That would explain the clouds of white smoke one sees in old films. Sort of like Lehmans at start up. Fact? Don't know.

catalinajack said:

I once had a World War 2 naval mechanic tell me that the reason propellers were turned by hand before the engine was started was to pump oil that had accumulated in the bottom cylinders enough of which that hydro-loc might occur and wreck an engine if it had been started without doing so. That would explain the clouds of white smoke one sees in old films. Sort of like Lehmans at start up. Fact? Don't know.

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Just did some research. I had it exactly right. Oil in bottom cylinders get you hydraulic lock, a blown jug, bent crankshaft, blown out spark plug, etc.

Yep. Remember now...... hydrolock in the bottom cylinders. You are all correct. And, come to think of it.... same reason I had to pull the gas pedal BACK with my hand (which acted as a valve lifter) for 30 seconds before letting go and starting a ....... Leopard I tank with a 27L 10 CYL multi fuel engine.

Ah, If I could only remember all I've forgotten.

If you are really concerned about dry bearings on startup you can plumb in a spring loaded resevoir and electric selinoid valve. The selinoid closes when you shut off the engine. when you turn on the key switch the selinoid opens and releases the oil from the canister lubricating the bearings. I consider it a waste of time and $$$. But then I dont have a problem letting a diesel engine sit for years with old oil, fuel, and heaven forbid antifreez and then starting it up and putting it to work. May even get around to changing the oil, but probably not this year. Never had a problem and I have more important things to worry about.

kulas44 said:

If you are really concerned about dry bearings on startup you can plumb in a spring loaded resevoir and electric selinoid valve. The selinoid closes when you shut off the engine. when you turn on the key switch the selinoid opens and releases the oil from the canister lubricating the bearings. I consider it a waste of time and $$$. But then I dont have a problem letting a diesel engine sit for years with old oil, fuel, and heaven forbid antifreez and then starting it up and putting it to work. May even get around to changing the oil, but probably not this year. Never had a problem and I have more important things to worry about.

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There ya go bud. Don't let a selinoid get in your way. Or a solenoid for that matter.

While I'm making fun of you I have to admit that I put 160,000 (!!!!!) miles on my college car and never got an oil change, and it ran like a bat out of hell, probably thanks to me flooring it at all times. Now I DID have more important things to worry about, of the coed flavor.

Still, if it was my $XX0,000 boat, I would think twice.

oscar said:

Yes I am an aviator, but radial engines were WAY before my time. I do remember though, that the engineer would "count the blades" as in so many rotations before the mags (ignition) were turned on. This WAS to get the oil flowing.

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No it isn't. It's to distribute fuel through the manifold and into the cylinders to ensure a smooth start when the mags are switched on. It's part of the technique used to minimize the risk of a backfire on startup. I do the same thing with the Pratt & Whitney R-985 on the planes I fly and it's got nothing to do with oil distribution.

My understanding of the reason for 2 full revolutions before fuel and ignition is the lowest cylinders can fill with engine oil (oil tanks are frequently above the lower cylinders in the wing) which would hydraulicaly lock the engine.

The starter is weak so will not usually do damage if the engine is full of oil.

With R3350 there was a hookup to pre oil the engine , by a hand pump.

And in cold weather operations the oil was diluted with gasoline to thin it for a cold start.

There was a NATOPS table of expected low temps , oil quantity reading and how many seconds the dilute switch needed to be held while the warm engine was ideling.before shutdown.

On start there was also a table for how many min. the CHT had to be above a certain temp , to evaporate the AV gas in order to go fly.

A half hour or more of extra fun for the crew.

FF said:

And in cold weather operations the oil was diluted with gasoline to thin it for a cold start.

There was a NATOPS table of expected low temps , oil quantity reading and how many seconds the dilute switch needed to be held while the warm engine was ideling.before shutdown.

.

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The R985 has the same system but we've never had to use it in our climate.

Lots of things I cant spell. Very few things about a diesel engine that I dont know. Can you say that,,,ozker.

Marin said:

No it isn't. It's to distribute fuel through the manifold and into the cylinders to ensure a smooth start when the mags are switched on. It's part of the technique used to minimize the risk of a backfire on startup. I do the same thing with the Pratt & Whitney R-985 on the planes I fly and it's got nothing to do with oil distribution.

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yup. And it's that "lack" of technique that was used to initiate greenhorns to the flight deck. There is nothing more scary than having one of those monsters backfire on you as you stand under one feebly holding up a fire extinguisher. Explosion, fire, smoke, pee. Everytime.

what_barnacles said:

. There is nothing more scary than having one of those monsters backfire on you as you stand under one feebly holding up a fire extinguisher. Explosion, fire, smoke, pee. Everytime.

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In addition to the scary part a backfire can also be very hard on the engine. Kenmore Air Harbor's engine overhaul mechanic once showed me the damage than can occur to a supercharger from the shock load of a backfire. Once he explained that I was even more cautious to avoid a backfire.

Marin said:

No it isn't. It's to distribute fuel through the manifold and into the cylinders to ensure a smooth start when the mags are switched on. It's part of the technique used to minimize the risk of a backfire on startup. I do the same thing with the Pratt & Whitney R-985 on the planes I fly and it's got nothing to do with oil distribution.

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Sit corrected once again. Thank you. Disclaimer, don't play with radials, just RB-211's....

Well, all you guys trump me, i know nothing about radial engines. But always admired them.

kulas44 said:

Well, all you guys trump me, i know nothing about radial engines. But always admired them.

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It's a remarkable (to me) design. For ages I didn't understand how they could work until I started flying a plane that has one and learned about the master rod and how the other connecting rods are all connected to it and not to the crank itself.

One of the most complex pieces of machinery I've ever seen is the Pratt & Whitney R-4360 (so named for the total cubic inch displacement of the engine). It has four radial rows of seven cylinders each. So twenty-eight cylinders, fifty six spark plugs. It started out as a 3,000 hp engine but this was eventually upped to 3,500 hp. The rows were staggered so to maximize the airflow around the cylinders.

It powered planes like the Goodyear F2G Corsair, Boeing B-50 Superfortress, the Boeing 377 Stratoliner, the Convair B-36, the C-117 Flying Boxcar, and the Hughes H4 Hercules (aka Spruce Goose). A couple of these in our GB36 would be pretty cool.

Another intriguing albeit inefficient engine is the rotary. It's use died out pretty quick after WWI but this was the one where the crank was bolted to the airframe and the cylinders and the attached propeller revolved around the crank. It made for a plane that had an amazing roll rate if the pilot wanted to turn in the opposite direction of the engine's rotation.

It's one more reason merging a fall layup and haul-out yields some nice congruence. The yard is not busy, if you need them or their hands. If you find 5 frozen seacocks as I just did, you don't float through the winter with 5 legs on pinochle. They quickly get serviced during the haul-out, which they require. Same with waiting six more months to change those overdue shaft and engine zincs...A nice time to refresh your cooling system too, as in anti-freeze.

After setting up an oil bath heater in your down low, you should be safe and warm, and come springtime - you're turnkey - and out of the engine room and topsides for the key ego stuff.