Well, this is unfortunate...
- Thread starter dhays
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dhays
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They gave me a ReCon manual that supplements the normal Cummins engine manual. I have not had a chance to read it yet. That will happened tomorrow and I will follow its advice.
I asked the mechanic today about break in (not their top Cummins tech but an experienced mechanic), he said follow the recommendations but... he recommended running it at a variety of power levels for a while rather than just my normal putting along at 1400-1500. He also said that regardless of what the book says, if it was him he would likely change the oil at 50 hours.
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dhays
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That is pretty much what the mechanic suggested and I will try to get some hours in doing just that before we go North. I'd rather find issues this weekend within reach of Vessel Assist, than when I am crossing Georgia Strait.
"He also said that regardless of what the book says, if it was him he would likely change the oil at 50 hours."
Oh my goodness yes! IMO 25 hrs. is when I'd first change it... then at 50 hrs.again. That said, I an extremely [some say overly] cautious when breaking in any engine; be it brand new or fresh rebuild/reman.
Oh my goodness yes! IMO 25 hrs. is when I'd first change it... then at 50 hrs.again. That said, I an extremely [some say overly] cautious when breaking in any engine; be it brand new or fresh rebuild/reman.
The Other Gary
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On my new Cummins Long Block there was a tag to change the oil at 10 hours, which I did even though it was still clean. I ran at various speeds throughout the first ten hours from 8 to 23 knots but never staying at one speed for long.
Per Tony Athens, Cummins have convex ring shapes when new. They wear to fully flat at about 300 hours. I am at that and my Racor vent filters are still clean and not a drop in the puke bottle.
Per Tony Athens, Cummins have convex ring shapes when new. They wear to fully flat at about 300 hours. I am at that and my Racor vent filters are still clean and not a drop in the puke bottle.
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dhays
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I looked at the material yesterday. Not a lot there other than the statement that the engine doesn't require any special break-in procedure. The first oil change is called for at 250 hours or 6 months. I won't go that long.
I did discover yesterday that the location of the oil dip stick is a bit different. Rather than a verity long dip stick that came up to the top of the engine, making it easy to reach but awkward to get to go back in smoothly, this one is on the port side of the engine and only 12 inches long. Really hard to get get to, but much easier to get in and out.
I did discover yesterday that the location of the oil dip stick is a bit different. Rather than a verity long dip stick that came up to the top of the engine, making it easy to reach but awkward to get to go back in smoothly, this one is on the port side of the engine and only 12 inches long. Really hard to get get to, but much easier to get in and out.
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When an engine gets broken in it generates heat.
A modest RPM , then a period of higher power , with a return to a modest RPM will allow the engine to change shape , as well as get rid of the added heat.
As the engine wears in longer and longer times can be spent at high loads.
Except to make a log reading WOT should seldom be carried , 10% less would be OK for high cruise. Watch for black smoke.
A modest RPM , then a period of higher power , with a return to a modest RPM will allow the engine to change shape , as well as get rid of the added heat.
As the engine wears in longer and longer times can be spent at high loads.
Except to make a log reading WOT should seldom be carried , 10% less would be OK for high cruise. Watch for black smoke.
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dhays
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My concern isn't too much time at a high power, but possibly too much time at a low power. Most of the last year I have been running at 1400 rpm. Based on my outing on Saturday, it looks like 1450 will be the sweet spot with this engine. 1450 gives 2.0 gph fuel burn and just over 7 knots (speed is tough to know since there is always a current).
For now, the plan will be to run it at a variety of power levels from 1400 to 2000. On Saturday I would run at an rpm for 20 minutes then bump it up or down and repeat. I want to do this over the next couple weekends before we head out for trip North. Then we likely will cruise at 1400-1500 with short periods at 1800 every few hours.
