Lehman sp120 oil consumption

[Eli27]

Good morning. As some of you may know I have purchased a 1979 albin 36 recently. It's got the lehman sp120. I have put 25hrs on the engine and I had to throw 1quart of oil in it so far.

From what I've read and have been told these engines normally have a light blueish smoke to them when they are cold and "almost" goes away when warmed up. And that's about what mine does now.

Initially when I bought it it smoked a bit more but was told if those engines sit or idle alot they tend to smoke more. A good run will probably clear most of it up. Well, I ran this baby for 8 hrs straight WOT while making my first trip from Newburyport to Cape cod with no issues. Perfect temp@170 oil pressure @40psi and no hiccups out of the engine.

When I got to the cape I was at sandwich marina. A couple days went by so I started the engine just to run it and see what kind of smoke I would get and I was sooooooo happy. Yeah, it smokes a tad on initial start up but within a few seconds it clears up super nicely. Being a mechanic on cars for over 20yrs and not knowing much about diesels (older ones) I would say I'm looking pretty damn good.

So the question, does the 1quart of oil seem like a lot for 25 hrs run time? And I would say on that 25hrs 16-18hrs of WOT 4-5 hrs of part throttle and the rest docking and idling through.

 

[jleonard]

It depends
When you fill the oil where is the level on the dipstick? Is oil leaking into the bilge?
I found, as many Lehman owners have, that because of the installation angle the engine leaks out the rear main seal and ends up in the bilge. However if you leave the level at “add” 1 quart the engine does not leak and you don’t have to add oil for many more hours.
Also in my opinion running 18 hours out of 25 at WOT ( 2500 rpm) is way too much for the Lehman.

 

[RT Firefly]

Greetings,
Mr. E. What is WOT (RPM)? I don't think the 120 is rated to run @ 2400 (WOT) for extended periods. I would consider it a medium duty diesel.

 

[sunchaser]

“So the question, does the 1quart of oil seem like a lot for 25 hrs run time? And I would say on that 25hrs 16-18hrs of WOT 4-5 hrs of part throttle and the rest docking and idling through.”

As already noted by Jay and RT you’re running the half century old engine at too high RPM. What needs to be answered are a few questions though.

First, what RPM yields 7.0 knots? Second, have you verified RPM accuracy with a photo tach?

 

[Bmarler]

Well I think you’ve cleaned out any buildup with the wot run.
I would think that amount of time at that high rpm would consume a little oil.
I bet normal operation will consume much less oil.

 

[Pete Meisinger]

Sounds like the oil level is too high.

pete

 

[Endeavor GB 32]

We have a Lehman 135, a slightly newer version of the 120 that you have. When I change the oil and filter I add 14 quarts (as instructed by Brian at American Diesel.) This puts the level right at the "full" mark on the dipstick. Over the first ? 10 or 12 hours it works its way down to the "add" mark (down 1 quart,) then stays there until I change it again at 100 hours. But we never run at more than 2000 RPM, either.
In previous experience with 3208 Cat engines I had the exact experiece over a lot more hours. This seems to be very common/normal.Good luck!
Regards,
Scott

 

[SteveK]

Sounds like the oil level is too high.

pete

This ^^^^
Marine engines are seldom installed level like when installed in a truck.
I learned over time that the dipstick may not agree with what the engine wants. If the oil is continually dropped to a level that suggests add oil and settles there, then the engine is telling you this is all I want.
Monitor the lower level and see if that changes. You only need enough oil to have a continuous suppply, to keep up the oil pressure. My twins were happy near the bottom add level and remained there until oil change.

 

[Comodave]

Bob Smith said to drain the engine completely, then add the specified amount of oil, then check the dipstick and see if it shows full. If not remark the dipstick to show full. If you fill to an incorrectly marked dipstick it will burn off the extra oil until it gets to the level the engine likes.

 

[Eli27]

I appreciate all the responses,,, interesting! I'm kinda happy with the results so far. I was hoping for an engine in decent condition,,, fingers crossed ?

 

[Comodave]

BTW, I agree that you should never run for 8 hours at WOT. Maybe 20 minutes a day or so.

 

[Caballero II]

Wot??

Good morning. As some of you may know I have purchased a 1979 albin 36....

....Well, I ran this baby for 8 hrs straight WOT....
....And I would say on that 25hrs 16-18hrs of WOT 4-5 hrs of part throttle and the rest docking and idling through.

Your question about oil use seems to have been well answered. But what about the statement that you are running A Lot of hours at WOT.

I'm hoping you didn't mean that, but just meant at full cruising speed all those hours? My Lehman 120 hp cruises 7.5 - 8 knots at 1700 rpm in a similar boat. WOT on these engines is rated at 2500 rpm, but that would only be for a short period.

Please let us know.

 

[RobertLeatch]

As an aside but perhaps relevant to the high WOT running, the 'acceptable' oil usage on my cat 3208s is always specified as oil usage per gallons of fuel consumed (not engine running hours). For the 3208s, 1 quart per 50 gallons of fuel burnt is considered Ok. In my case (1500 rmp / 8 nm/h / 10 liters) that turns out to be about 1 liter every 20 hours.

 

[twistedtree]

On these Lehman's is sure sounds like it's a case of over-filling relative to the engine's installation angle, and that once the level is down where it should be, consumption becomes low.


Maybe I'm spoiled or lucky, or both, but I have never owned an engine that used more than perhaps one quart of oil between oil changes, and most not even that. And that includes some engines with pretty high mileage/hours.


I know a lot of manufacturers specify as normal what I would consider to be high consumption, but I always figured that was to eliminate it as a possible warranty claim. In practice, I think a quart of oil every 50 hrs, or even every 100 hrs seems really excessive.


What are others seeing in practice? Is high consumption like that really typical in a normally operating engine?

 

[psneeld]

My old Lehman 120 engine which should still be going strong between 4-5000 hrs would burn a quart or so every 20hrs or so.

My 3208s still going strong at 6000 hrs were burning around a quart every 30 hrs IIRC..

The Lehman 120 also tended to leak oil out the rear seal if over filled if it had some hours on it.

 

[ronobrien]

Intermittent full load running is good for a diesel for short (10-15 min) periods. Running at full load for 8 hours you might be glad it used some oil. Try running it more moderately and see what the consumption is. I wouldn't think that 1 QT every 50 hours to be too excessive for an older design diesel. 1 QT @ 25 hours is a bit high (general knowledge, not specific to FL), but running at full load can increase that. How many hours on the engine when you bought it?

 

[IRISHT]

Good morning. As some of you may know I have purchased a 1979 albin 36 recently. It's got the lehman sp120. I have put 25hrs on the engine and I had to throw 1quart of oil in it so far.

From what I've read and have been told these engines normally have a light blueish smoke to them when they are cold and "almost" goes away when warmed up. And that's about what mine does now.

Initially when I bought it it smoked a bit more but was told if those engines sit or idle alot they tend to smoke more. A good run will probably clear most of it up. Well, I ran this baby for 8 hrs straight WOT while making my first trip from Newburyport to Cape cod with no issues. Perfect temp@170 oil pressure @40psi and no hiccups out of the engine.

When I got to the cape I was at sandwich marina. A couple days went by so I started the engine just to run it and see what kind of smoke I would get and I was sooooooo happy. Yeah, it smokes a tad on initial start up but within a few seconds it clears up super nicely. Being a mechanic on cars for over 20yrs and not knowing much about diesels (older ones) I would say I'm looking pretty damn good.

So the question, does the 1quart of oil seem like a lot for 25 hrs run time? And I would say on that 25hrs 16-18hrs of WOT 4-5 hrs of part throttle and the rest docking and idling through.

We owned a SP 135 for over 20 years and this is my experience:

- Engine produced in November 1986
- Mounted at 12.5 degree angle in a Hinckley 49' CC ketch
- Logged approx 2600 hours
- Followed oil fill level of 20 qts as indicated in Lehman operating manual
- Oil consumption approx 1 quart every 10 hours - bilge very oily
- Learned from Brian at American Diesel that correct oil fill S/B 14.5 qts
- Original dipstick barely registered with 14.5 qts
- Fabricated new dipstick using spring steel and after draining all oil refilled and marked stick at app 5 qts, 13.5 qts, and 14.5 qts
- As far as i can now tell consupmtion is around 1 qt every 100 hours
- Ran engine at 2200 RPM for 15-20 minutes every 24 hours -normal operation at 16-1800 RPM pushed 40,000 lb disp 6-7.5kts
- Never heard a discouraging word about the engine if properly taken care of -

 

[mvweebles]

In practice, I think a quart of oil every 50 hrs, or even every 100 hrs seems really excessive.


What are others seeing in practice? Is high consumption like that really typical in a normally operating engine?

My ancient Perkins 4.236 75hp uses about 1-qt every 125 hours. I wish it was less, but doesn't seem excessive. I started in Ensenada and topped-off in La Paz, something like 800 nms later.

1-quart every 20-hours would drive me nuts. I just did 38-hours from La Paz to Mazatlan. Adding a quart midway does not sound ideal.

Peter

 

[motion30]

You ran a 40 some year old loader at wide open throttle for 25 hours? I think you are fortunate oil is the only thing you need to put in that engine

 

[ronobrien]

You ran a 40 some year old loader at wide open throttle for 25 hours? I think you are fortunate oil is the only thing you need to put in that engine

I do agree with your analogy. That is the catch when comparing marine diesels to land based counterparts. The land based diesels run at load intervals at varying throttle settings, whereas marine diesels run under load 100% of the time at typically consistent throttle for extended times. It makes for a very difficult comparison.