Oil weight for older diesels?

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manyboats said:
...Re the oil capacity it looks like ther'e were things Lehman overlooked when they converted the truck and tractor engine to marine use. Not very smart of them to overlook the shaft angle element of the marine conversion...
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It wasn't Lehman that overlooked the oil capacity but the boat builders who put the engines in. The Lehman Power manual specifically refers to either remarking the dip stick or shortening the "tube" that the dip stick goes into. The manual even goes as far to mention the need to de-burr the tube if you shorten that vs remarking the dipstick.
 
Larry M said:
It wasn't Lehman that overlooked the oil capacity but the boat builders who put the engines in. The Lehman Power manual specifically refers to either remarking the dip stick or shortening the "tube" that the dip stick goes into.
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The same with Perkins 6-354's. Different installers either did or didn't pay attention to the manufactures instructions. Mine were marinized by Charles E. Smith and the oil volume on the dip sticks were right on. Hard to say what Smith marinized, since everything was Perkins OE parts? Maybe he provided the Delco starters and Alternators? :lol:

Tried 10-30 W oil, but the engines liked it too much and ate it freely. Have used 30 W ever since.
 
Cummins are the same reference the tilt angle and the shallow oil pans. It is also recommended to re calibrate the dipstick...or most people just fill to the bottom of the safe range...which should be 13 quarts.
 
Manyboats, you are correct! You forced me to get out my manual and it is indeed 120 at 2500 rpm, WOT is also 2500 with a load, 2650 no load.

I re-read my post and I still stand by what I wrote, WOT is not inherently bad for a diesel, it is the manufacturer's max continuous power. It's arguable (no kidding) about how reasonable it is to make an old man run, but I believe if it fails at WOT, it will fail soon anyway and it's better to find out under controlled conditions. WOT will check all your engine systems and point out any weaknesses. I swallowed the whole WOT pill because it's logical.

I used to operate large radial engines and learned first hand about manufacturer's power limitations, useful information that can be applied to ANY engine from small outboards to large jet engines.
 
I have taken Bob Smith's course twice. The second time he stated that there was an error in the Lehman Sabre manual about the oil capacity requirement of the FL 135. the manual states 19.76 US quarts (page A6). Bob says it should be 14.5. I clarified this later with Brian Smith and he reaffirmed 14.5 quarts, regardless of the inclination of the engine. The stick should be remarked. A PO has drawn a line through the error in the manual and written in 14.37 quarts. The main engine seal was replaced at about 2000 hours, probably a result of an overfill of oil. A longtime FL mechanic in Steveston also confirmed with me 14 litres. He remarked the oil pan was huge in the engines.

Jim, Sent from my iPad using Trawler
 
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I have well over 3200 hours on my Ford Lehman diesels which are 1966 Dagenham Fords. I use Delvac 1 and it is a multi weight oil. After I switched to Delvac 1 my smoking went down. I swear by it. The sheen also dropped dramatically and is almost non existent when it's warmed up.

Before that I used Rotella last and agree for the money, it's very good.
 
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Gents, Let me throw in my 2 cents worth! We have a boat in the British Virgin Islands using a Perkins 4-108 50 HP diesel. The engine is unknown high time. Recently the gentleman responsible for our maintenance conferred with a number of diesel gurus down there and the conclusion was to switch from Rotella 15W-40W to the straight 40W for the hours on the engine and temps down there. Supposedly better lubricating qualities under those conditions. George
 
Xsbank said:
WOT ..... is the manufacturer's max continuous power.
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Be careful here. WOT is simply WOT....whatever you get when you firewall the throttle. If it matches what is in the manual(max RATED power), THEN you are correct. But usually it does not.

Also, Max continuous and max rated power can be two different numbers(and likely different than WOT)....

My previous boat had a Yanmar 4LHA-STP. Max rated power was 240hp@3300RPM. Max continuous was 190hp@3100RPM. WOT was 3600RPM...comfortably underpropped.
 
Baker said:
Be careful here. WOT is simply WOT....
My previous boat had a Yanmar 4LHA-STP. Max rated power was 240hp@3300RPM. Max continuous was 190hp@3100RPM. WOT was 3600RPM...comfortably underpropped.
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And out of gear at WOT - high idle - is 3700rpm.

The new member should realize there is a whole world of difference between the means and rate of power extraction between a marine diesel and a corncob radial or gas turbine.
 
Of all the technical things I've read over the years on lubrication there is only one the engineers all agree on. The higher the viscosity the less the wear. The inclination to use thin oils these days is to minimize friction and maximize car sales. One mpg better on the window sticker is worth the lives of several thousand engineers. Marin and I talked about this long ago yes I'm using 5-30W synthetic lube in my newer car that specifies that. Bummer .... it costs $50 just for the lube and filter. But I still use 30W in my boat diesel.

I don't remember it mentioned but WOT on the controls may not be WOT on the engine. One needs to check that the cable rotates the throttle shaft all the way to max. If it dosn't some guys may think ther'e overpropped and in fact they could be underpropped.
 
It's common knowledge that manuals are written by third parties usually. I have a friend who is in the business and he writes manuals for aerospace and commercial airplanes. They don't have all the answers and use material that is passed on over and over again.

Look at oil. The new oils lubricate so much better than older oils and they have to be listed as multi weights. Going back to a single weight oil isn't the wisest of choices IMO. Having the best lubrication I can get for my engine is.
 
Capthead said:
It's common knowledge that manuals are written by third parties usually. I have a friend who is in the business and he writes manuals for aerospace and commercial airplanes. They don't have all the answers and use material that is passed on over and over again.

Look at oil. The new oils lubricate so much better than older oils and they have to be listed as multi weights. Going back to a single weight oil isn't the wisest of choices IMO. Having the best lubrication I can get for my engine is.
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I think your first paragraph is misleading. Manuals are PUBLISHED/designed by third parties. The "first party" is the provider of the information for the manual.
 
Capthead wrote;

"Look at oil. The new oils lubricate so much better than older oils and they have to be listed as multi weights."

Your'e getting viscosity mixed up with lubrication abilities. The synthetics have multi-viscosity properties w/o VI improvers added. That dosn't directly make them a better lubricant. Higher vis reduces engine wear so just use a higher vis oil.

"Going back to a single weight oil isn't the wisest of choices".

There's no "going back". Ther's no old oil and new oil. One should choose the best lube for the job at hand. If you need synthetic for super high temperatures of a racing engine or a high output turbocharged sports car engine use synthetic. The only reason to need synthetic is for extreme engine temperatures or/and cold weather starting. The only reason for dino oil multi-viscosity is for cold weather starting or the necessity to work an engine before warming to the usual operating temperature.

So in our cars we find multi-vis oil to be an advantage. I use MV oils in all my cars. But for boats like our trawlers that always warm up slowly there is no need or advantage whatsoever to using synthetic or multi-vis lubricants.
 
Baker said:
I think your first paragraph is misleading. Manuals are PUBLISHED/designed by third parties. The "first party" is the provider of the information for the manual.
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As many of you know I used to fly ultralight aircraft and we used very high performance 2 stroke engines that regularly ran at cylinder temperatures above 400 degrees. Dino oil was marginal at those temperatures so many of us used synthetic oil .. me included. I used (for years) Bell Ray MC-1 synthetic racing lubricant and it held up well. It's viscosity is so high that on the bottle it said "will not flow in auto oil injection systems". It was the highest viscosity one could get.

But the engine I was running did not recommend using synthetic oil of any kind. I was close to the recreational industry and know that the reason that they didn't recommend the synthetic is that they didn't have time to test the synthetic oils. There were many different kinds and synthetic is not like dino oil in that there was several way different base stocks that the synthetic "oil" was made of. So if they were going to recommend one they had to test them all. So they didn't recommend the best oil for their engines. At least that was what was common knowledge among us UL fliers.

So using something other than what a manufacturer recommends can be the best thing to do .......... but that is rare.

The oil ratings on the can like "SJ" (or whatever) is important. It's the best (other than what the manufacturer recommends) way to judge if you have the right oil for your application.
 
manyboats said:
Of all the technical things I've read over the years on lubrication there is only one the engineers all agree on. The higher the viscosity the less the wear.
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You need to read more or find a different library ...

Too high a viscosity is just as problematic as too low. There is a range of viscosity that is best for a given application, outside that range either way will increase wear.
 
Thanks for all the info .

So I got and applied all the advice I could...
Changed oil with 15/40 rotella at 12.5(recommended but scary way below min)
Cleaned air filters
Cleaned intercoolers
Ran out almost all old fuel and put in fresh ( ran her hard for 6 hrs)
Injector service
Wolverine pan heaters

Tried to take last advice and calm the heck down
She still smokes like a bitch
So if compression was ok at survey, what's left?
Valve guide seals?
Rings?

Are there any cheap things I missed before I start spending a lot?
 
Why don't you wait till you see if you actually use any oil. From what I read of this thread, I don't think you are sure if it is oil smoke or white smoke (unburned fuel).
Don't pay much attention to what it does b/4 it warms up, check your thermostat for proper opening temperature, and don't run without propeller load, start, castoff, move off.
 
Submarine deckhand said:
Are there any cheap things I missed before I start spending a lot?
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You are close to American Diesel who know Lehmans, very well. You may want to contact them for recommendations on the next steps.

BTW, 2000 hours can mean lots of future use is left, or not, based upon the previous owners' care and attention. Also, I can't recall if you said you can reach full rated RPM, meaning a possibly over propped condition which can lead to lots of black smoke.
 
She still smokes like a bitch
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FWIW I know only two owners of boats with 275 Lehmans...they both smoke like a bitch. They run really well regardless.
 
RickB said:
You need to read more or find a different library ...

Too high a viscosity is just as problematic as too low. There is a range of viscosity that is best for a given application, outside that range either way will increase wear.
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Higher viscosity = less wear.

Didn't even touch on any reason not to use too high a viscosity. I'm not about to fill my engine w 60W. But I believe my engine will wear slower w 40W than 30W. That's all.
 
I would follow Sun Chaser's advice...phone American Diesel. Start with Brian and see where you get and then follow up with Bob (his father) who knows more than anyone about these engines. You may need new injectors.

Incidentally, brought an old time mechanic onboard my boat. He knows these engines well. Based on the number of hours I had on them I had felt I was getting near a replacement of the injectors. He reved up the engine to test the response and said they were fine.

Jim

Jim, Sent from my iPad using Trawler
 
Didn't even touch on any reason not to use too high a viscosity. I'm not about to fill my engine w 60W. But I believe my engine will wear slower w 40W than 30W.

Exactially backwards from the one or 2 engine folks I know.

There concept is the thinner oil (if you can pay for its consumption) will lubricate the engine better.

This is why you see heavy diesels with 15W- 40 or now 10W -30 as fleet lube choice .

AN old thumper from the dark ages will still prefer thinner oil ,(30 over 40) its just multi weight , or synthetic that gives hassles to the antiques.

Even poured babbit bearings use the oil as modern shell bearings do.The pumped oil is a liquid cushion , not a film.
 
FF,
I was telling about what I had read many times. But I do buy into it to some degree.

I'm not an engineer so I really don't know. And as to things of this nature (like what oil to use) you can often get good advise from mechanics but information from mechanics is not much more than what my opinion would be .. or yours. Engineers advice is the best you can get and if his advise is in line w what the mechanic says all the better. All engines have specifications and how hard you should run the engine and what oil to use will be in those specifications. Not only the viscosity but what type usually designated by two letters. If the engine is too old to have modern products represented then I'm not sure what the best option would be. If I had a Lehman or old Perkins I'd find a modern engine currently being made w the same engineering and design features as the old engine. My Mitsu is probably a good example. Using oil that those engineers recommend may be a good move but it isn't foolproof. Probably better than a mechanic's opinion though. I'd use 40W in hot climates and 30W everywhere else except where engines need to be started whereas the engine is at freezing temperatures (like trucks) and then I'd use multi-vis as required. But if an engine's cranking speed is normal multi-vis is not needed. But again engineer's advice is usually the best advice.

Capthead says "Look at oil. The new oils lubricate so much better than older oils and they have to be listed as multi weights." I'm not buy'in into the "lubricate so much better" part but the're is a good point in that quote. All dino oil needs viscosity improvers to have multi-vis properties but synthetics flow at multi-vis rates w/o any additives to make them do so. I don't see any dino 5W40 oil. It looks like viscosity improvers can only do so much. I have a car now that specifies full synthetic oil and I comply but other than the viscosity element I have never seen or heard anything to indicate that syn lubricates better.
 
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>If the engine is too old to have modern products represented then I'm not sure what the best option would be.<

Almost all the improvement in modern oils is in the additive package , that 20-25% of the oil that carries detergent ,anti rusting and the other dozen or so things needed by engines being forced to eat there own exhaust by the Air Police.. EGR

The BEST option is always DA Book from the mfg , but these change over time.
 
SeaHorse II said:
This is interesting!

Synthetic Oil | Why Use
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Not very unless you like and buy promotional stuff. You see that is from Mobile 1. I see that the only significant advantage is in synthetics ability to handle heat. Dino oil even does that well unless you're running a heavily turbocharged engine very hard gas or diesel. But for NA diesel engines Dino oil has no significant short comings at all. For engines developing 1/2 hp per cu in changing oil often and using Dino oil has no downside worth mentioning.

You can also use hard racing bottom paint on your trawler but ..........................
 
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I see that the only significant advantage is in synthetics ability to handle heat.

The reason it is used in modern cars and trucks is it can be scraped off the cylinder walls easier by the oil control rings.And thin is cheaper to pump.

This aids power and fuel mileage , but the quick drain down hurts storage as cylinders rust sooner.
 
FF says "The reason it is used in modern cars and trucks is it can be scraped off the cylinder walls easier by the oil control rings." I thought oil control rings "controled" the amount of oil LEFT on the cyl walls. Not trying to scrape off but leaving some.

FF says "And thin is cheaper to pump." By cheaper I assume you mean takes less power to pump to get better mileage. True of course.

FF says "the quick drain down hurts storage as cylinders rust sooner". You are the only person or source I've ever encountered that says that. And in my ultralight aircraft experience the opposite seems to be true. You can see the thick oil on the piston when the exhaust manifold is removed. The piston was gooey w synthetic lubricant. But the syn oil itself was a very viscous racing oil. A simple experiment in my garage should put that one to rest. Perhaps it comes from the fact that almost always when people use syn oil they use less viscous oil and it would drain off the piston and cylinder walls a bit more redilly having nothing to do with the oil being synthetic or not.
 
manyboats said:
FF,
I was telling about what I had read many times. But I do buy into it to some degree.

I'm not an engineer so I really don't know. And as to things of this nature (like what oil to use) you can often get good advise from mechanics but information from mechanics is not much more than what my opinion would be .. or yours. Engineers advice is the best you can get and if his advise is in line w what the mechanic says all the better. All engines have specifications and how hard you should run the engine and what oil to use will be in those specifications. Not only the viscosity but what type usually designated by two letters. If the engine is too old to have modern products represented then I'm not sure what the best option would be. If I had a Lehman or old Perkins I'd find a modern engine currently being made w the same engineering and design features as the old engine. My Mitsu is probably a good example. Using oil that those engineers recommend may be a good move but it isn't foolproof. Probably better than a mechanic's opinion though. I'd use 40W in hot climates and 30W everywhere else except where engines need to be started whereas the engine is at freezing temperatures (like trucks) and then I'd use multi-vis as required. But if an engine's cranking speed is normal multi-vis is not needed. But again engineer's advice is usually the best advice.

Capthead says "Look at oil. The new oils lubricate so much better than older oils and they have to be listed as multi weights." I'm not buy'in into the "lubricate so much better" part but the're is a good point in that quote. All dino oil needs viscosity improvers to have multi-vis properties but synthetics flow at multi-vis rates w/o any additives to make them do so. I don't see any dino 5W40 oil. It looks like viscosity improvers can only do so much. I have a car now that specifies full synthetic oil and I comply but other than the viscosity element I have never seen or heard anything to indicate that syn lubricates better.
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Synthetic oils are about 600% better at "lubrication", and significantly better are removing heat from engine components that are "oil-cooled" (such as the underside of Pistons). This enhanced cooling is due to turbulent vs laminar flow (syn are more turbulent in nature)

Average film-strength (ability to keep two surfaces separated by an oil film) is about 500 psi for conventional oil, and about 3,000 psi for synthetic).

This is due to a more consistent length of each oil molecule, which can be thought of (analogized) as little pieces of yarn. In conventional, some are very short and others are very long, i.e. inconsistent. In Synthetic oil all the molecules are very close to each other in length.

You will find that where lubrication is critical, synthetic is the only oil used.

Furthermore, synthetic oil is much more durable, requiring much less-frequent changes.

Even in low-end auto-racing, such as NASCAR, synthetics rule.
 
Robert Durio said:
You will find that where lubrication is critical, synthetic is the only oil used.

QUOTE]

Nice advertisement.

Here is a simple question Robert, why does Cat not recommend a longer oil drain time for synthetics vs Dino in their off road equipment warranty programs? In fairness, Cat does suggest, but not insist on synthetics for Arctic work.
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