Official Caterpillar3116/3126 Thread

The data above was taken at different times, and under different conditions, mostly smooth seas.

The data below was taken with smooth seas, but taken at ONE time only, and was incrementally done in 100 RPM increments.

50% fuel and 50% water with full tabs.

At this load factor the sweet spot is higher than the anticipated "2150" number I was previously assuming.

At the 50% load factor 2300 seems to be the magic number for this boat, which also goes along with the "sound" and the "feel" at that RPM - feels like the engine is not working as hard as at 2000-2200 range.

Next time I fill up for fuel and water I'll do the same test to see the difference fully loaded, which will likely yield a different story.

BEST !

RWS
Fuel_Burn_FloScan_0822_50PercentFuel.jpg
 
Here's the breakdown:

Overnighted at:
  • Marco Island - one night
  • Marathon - 2 nights
  • Key Large - one night
  • Miami - 2 nights
  • Las Olas (Ft Lauderdale) 2 nights
  • North Palm Beach - 2 nights
  • Stuart - one night
  • Indiantown (on the Okeechobee waterway) 1 night (the banjos were playing, like really LOUD)
  • Sweetwater - one night
  • Boca Grande - one night

Totals:
  • 16 nights
  • ten "trips"
  • 5 OWW locks
  • 660 statute miles
  • 702.7 gallons of fuel (after discounting .82 GPH for the Kohler genset)
  • .94 SMPG
  • genny used no oil
  • CAT 3126 burned 3 qts oil each
  • These are FAPS blocks (that's right) currently with 614 hours

I purposely did not wash the exhaust areas of the boat during this trip.

Here's evidence of the lack of soot:

IMG_1981_Resized.jpg
 
Here's the Miami to Las Olas arrival - last half is the best part.

Miami to Las Olas Arrival - YouTube

Truly a wonderful experience.

Not having to go back over the same course was an added bonus.

Was a great opportunity to improve my own skills by learning the idiosyncrasies of the 450 DA, and with the Floscans, the surprise at how different the numbers are as one burns off fuel, AND at higher RPM's.

The only mechanical items were the 4 stbd screws holding the fwd berth sliding door track ALL backed out (this must have been going on for years) and I needed to replace one of the Bosch fuel relays (10 minute job)

Otherwise she performed like a champ and feels even better after this run.

Boat was a dock queen with 435 hours at purchase 20 months ago, and yes, she passed the CAT blowby test with flying colors.

BEST !

RWS
 

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Don't know where you got the 225 hours number. Perhaps you meant miles?

I also don't know what is considered "normal" for the 3126.

I do know that most of this run was on plane, and my gut tells me that 3 quarts per engine over 660 statute miles is a good result.

Perhaps others with more depth of experience on oil usage/hours/miles will chime in.

BEST !

RWS
 
Maybe A Dancer said:
Don't know where you got the 225 hours number. Perhaps you meant miles?

I also don't know what is considered "normal" for the 3126.

I do know that most of this run was on plane, and my gut tells me that 3 quarts per engine over 660 statute miles is a good result.

Perhaps others with more depth of experience on oil usage/hours/miles will chime in.

BEST !

RWS
Click to expand...
I meant gallons, not hours. I EDITED my comment. I have used mine about 100 hours since I purchased the boat last year with no measurable (on the dipstick) oil burn, so now I am curious.
 
Other than my own experience, I can't comment on 3126 oil usage.

In the 1980's I ran a fleet of MACK R686ST diesel trucks with MACK ENDT676 6 cylinder engines at 672 cubic inches.

These trucks had the ESI (Extended service interval), 54 quart oil system and 3 oil filters.

This equipment was run 2 shifts a day/5 days a week and yes, the oil was checked at the beginning of each operating shift. This equipment did use some oil as was normal and we kept a record of what they consumed to see if there was a trending problem, and to keep up with the oil sampling records.

I was initially happy with the 3 quarts over 660 miles. and a clean transom.

Maybe I shouldn't be???

BEST!

RWS
 
Maybe A Dancer said:
Other than my own experience, I can't comment on 3126 oil usage.

In the 1980's I ran a fleet of MACK R686ST diesel trucks with MACK ENDT676 6 cylinder engines at 672 cubic inches.

These trucks had the ESI (Extended service interval), 54 quart oil system and 3 oil filters.

This equipment was run 2 shifts a day/5 days a week and yes, the oil was checked at the beginning of each operating shift. This equipment did use some oil as was normal and we kept a record of what they consumed to see if there was a trending problem, and to keep up with the oil sampling records.

I was initially happy with the 3 quarts over 660 miles. and a clean transom.

Maybe I shouldn't be???

BEST!

RWS
Click to expand...

I think it’s fine. You’re clearly not burning oil as the relief ports aren’t staining up the hull, I assume the engines don’t smoke much after warmed up? If the oil cooler was leaking you’d know that, too.

a quart on a dipstick that measures roughly 7 gallons is next to impossible to measure anyway.
 
comrades,

i am about to swap the starboard 3116 in my '99 400.

i have seen one diagram indicating that both engines spin clockwise, as viewed from tail end of engine.

i can no longer turn over the starboard engine.

Can you please confirm that both engines spin clockwise?

i suspect that one of the transmissions (starboard maybe) reverses the shaft rotation. . .

thanks for your help
jerry
507 358 9520

i would appreciate any wise insights on swapping engines (i've stripped down the old bad starboard engine, it is ready for a yard to pick it out w a 14' fork lifting 1200#! good times!)
 
Strecker25 said:
I think it’s fine. You’re clearly not burning oil as the relief ports aren’t staining up the hull, I assume the engines don’t smoke much after warmed up? If the oil cooler was leaking you’d know that, too.

a quart on a dipstick that measures roughly 7 gallons is next to impossible to measure anyway.
Click to expand...

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

THANKS !

Oil pressure is up to spec and she passed the CAT blow-by test by Quinn Cat in Los Angeles.

She runs out great.

Zero smoke, i mean really - zero, nada, none - no smoke no soot now that the props ar dialed in.

From the helm she feels "better" now than at the start of this run.

Can't really explain or quantify it, kinda like that book I read in the 1970's called ZEN AND THE ART OF MOTORCYCLE MAINTENANCE.

I'm really happy with this boat, the improvements, the focus on restoring her original reliability and the way she is turning out overall.

During this trip I was completely surprised by the number of comments received on her from people who went out of their way to talk about this 27 year old boat, including two former Sea Ray salesmen, one of whom ran the 450DA to the Bahamas back in the day...

I digress.....

as per my M.O.

BEST !

RWS
 
mrsrobinson said:
@UnsaltedGL I documented cleaning my heat exchangers on my YouTube page, link is below, check out "Caterpillar 3126 Service and Maintenance" and you will see a video where I pulled the end cap off of one of the heat exchangers, you will then see what we are talking about. I replaced the O Ring when I did this.


See the ring, and the tubes? One set of tubes is for raw water, the other is for the coolant.
Click to expand...
Both sets of tubes flow raw water. The coolant flows around the outside of the tubes.
Raw water flows through the half that looks clogged. Then it turns around at the other side and flows back. That is a fact
 
Jerry Carr said:
comrades,

i am about to swap the starboard 3116 in my '99 400.

i have seen one diagram indicating that both engines spin clockwise, as viewed from tail end of engine.

i can no longer turn over the starboard engine.

Can you please confirm that both engines spin clockwise?

i suspect that one of the transmissions (starboard maybe) reverses the shaft rotation. . .

thanks for your help
jerry
507 358 9520

i would appreciate any wise insights on swapping engines (i've stripped down the old bad starboard engine, it is ready for a yard to pick it out w a 14' fork lifting 1200#! good times!)
Click to expand...

Straight shafts on a DB. Starboard side counter rotates. Motors turn counterclockwise looking at the flywheel.
 
Riptide III said:
Both sets of tubes flow raw water. The coolant flows around the outside of the tubes.
Raw water flows through the half that looks clogged. Then it turns around at the other side and flows back. That is a fact
Click to expand...
Didn't know this, thanks for sharing.
 
mrsrobinson said:
Here's the thing, my question was to you, not other members. Answer my question. And I'm posting this in a public thread because you started this. Why do you have issues with me that you continue to post in public threads? Why did you take a minute of your time as you alleged to post what you did, and continue with the stupid shit with me?
Click to expand...
3116/3126 thread
 
Maybe A Dancer said:
Other than my own experience, I can't comment on 3126 oil usage.

In the 1980's I ran a fleet of MACK R686ST diesel trucks with MACK ENDT676 6 cylinder engines at 672 cubic inches.

These trucks had the ESI (Extended service interval), 54 quart oil system and 3 oil filters.

This equipment was run 2 shifts a day/5 days a week and yes, the oil was checked at the beginning of each operating shift. This equipment did use some oil as was normal and we kept a record of what they consumed to see if there was a trending problem, and to keep up with the oil sampling records.

I was initially happy with the 3 quarts over 660 miles. and a clean transom.

Maybe I shouldn't be???

BEST!

RWS
Click to expand...
What temp thermostat are you running? I never checked mine but i run at 180 degrees. I do get occasionally soot
 
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