[Gene Fuller]

The standard configuration for the Nordic Tug 44 has been 100% 24 volt since its inception about 10 years ago. (Update from the previous Nordic Tug 42).

Of course these are highly custom boats so anything is possible. However, it is very likely to be a completely 24 volt system, including all engine and battery related items as well as lighting, appliances, etc.

[Gene Fuller]

The recommended torque for 5/8-18 (grade 8) bolts is on the order of 240 ft-lbs. Good luck reaching that torque in the cramped space available. Not easy! Any stronger bolts with a higher torque spec would be a waste of time.

Keep in mind that the role of bolts in this application is squeezing the flanges together, not by directly carrying the rotational load. The rotation load is carried by the friction between the flanges. Each properly torqued bolt provides over 20,000 pounds of compressive force, so the total friction between the flanges is very large.

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Tony Athens

[Gene Fuller]

If the water hose is connected to the output side of the pump (“high pressure port”) and there is no water lift muffler then the arrangement should work fine.

It does not matter if the seacock is open or closed in that case.

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Tony Athens

[Gene Fuller]

A 6-point socket would be a bad choice. Get a 4-point socket. Only a few dollars in that size.

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Dennis Cioffi

[Gene Fuller]

The exact details probably don’t make much difference, but keep in mind that the pump RPM is generally not the same as the engine RPM.

[Gene Fuller]

Sorry, I was not trying to correct anyone’s terminology.

Just pointing out that the starters discussed here are not the same as in an old Ford Fairlane. Those really did have a genuine bendix starter, which is a cheap alternative for relatively low-end use.

Because of the extra electrical power needed to push the pinion in a Cummins starter the mag switch is quite important.

[Gene Fuller]

I guess your definition is different from mine. I learned many decades ago that the Bendix was a sliding pinion on a coarse multi-start thread on the starter motor shaft. The pinion was forced into the flywheel ring gear as the starter motor spun up. There was no other force, electrical or otherwise, to directly actuate the pinion-flywheel mesh.

The standard diesel starter uses a solenoid to push the pinion through a lever arrangement. I have never heard this called a Bendix before today.

Learn something new every day.

[Gene Fuller]

I don’t think these starters have a Bendix, which is a purely mechanical device. Instead they have a toggle arrangement that pushes the pinion into the ring gear on the flywheel.

A Bendix, as used on cars for decades, does not require any electrical power to operate, only the spinning of the starter motor. The toggle arrangement, on the other hand, requires electrical power to actuate.

I had a previous boat with a much smaller diesel engine that had many problems with the starter arrangement for the early model years. The boat manufacturer skipped using a mag switch, and after a few years the owners begin to have problems with erratic starts. Corrosion, weak batteries, and other old-age stuff begins to take a toll.

My boat was a bit newer and the manufacturer had added a mag switch. I never had any start problems, and I did not hear of anyone else with problems.

Use the mag switch.

[Gene Fuller]

I’ll try again.

If the tachs and speeds are accurate the differences in the following excerpt cannot be related to engine performance in any way. It is possible your “corrections” are not quite right or there are real “non-engine” differences.

 

[Gene Fuller]

You may be chasing the wrong issue.

At a given RPM, such as 2200, any differences in speed are NOT due to the engines. Your friend’s boat may be lighter, better trimmed, cleaner, more efficient props, etc. etc.

There could be engine problems, of course, in addition to the boat differences.

[Gene Fuller]

I looked at the safety data sheets for the two product numbers. There are some small differences in the solvent mix. Probably related to environmental issues in some states.

I believe the image Rob showed is probably not 100% correct, but more like 99% correct. I do not expect a user would see any difference.

[Gene Fuller]

I believe in a previous post you said you have a Monk 36. In that case I recommend getting specfic advice from the Monk owners forum. There may be details that you would never find in a random YouTube video.

Generically the process is very, very simple.

Step 1: Drain oil

Step 2: Change oil filter (fill new filter with fresh oil before installing)

Step 3: Refill with fresh oil.

The exact details will depend on the access you have and any extra equipment such as an oil changer (Reverso or Jabsco most commonly.)

The potentially tricky part is the drain step if you do not have an oil changer. Access to the drain plug is often difficult if you have to reach it manually.

One thing where I disagree with Steve Lewis is that I never use the oil changer to refill. Why push the remaining sludge in the drain hose back into the engine or transmission? The QSB 5.9 takes only a bit over 3 gallons, so it is not a big problem to just use a funnel to pour the new oil into the filler cap on the top of the engine. The transmission may be more difficult, but it takes only a few quarts.

[Gene Fuller]

Should I shut fuel off before replacing?

If there is any chance that your fuel tanks would drain or siphon then shutting off the fuel would be a pretty good idea. Depends on your boat layout.

I would shut off the fuel in any case. Unless there is some really unwieldy arrangement it only takes seconds to do.

 

[Gene Fuller]

I don’t agree that you should be using jumpers, even in the short term. In the short term you should be using the parallel switch to facilitate charging of the house bank.

That will certainly help determine if the overall charging system is working, but it adds an extra complication beyond the ACR by itself. The jumper is kludgy at best, but it completely targets the ACR and only the ACR.

There could be other wiring issues beside the ACR.

[Gene Fuller]

The alternator will not care if the charger is connected, as long as the maximum voltages are more or less the same. (I assume this is a standard 12 volt system with a maximum voltage in the mid-14 volt range.) The alternator will just see what looks like a fully charged battery and will not try to produce any extra voltage or current.

[Gene Fuller]

The Blue Sea charging relays will not combine if the ground connection is bad. A standard installation places a fuse in the ground lead to the ACR. (Unusual to fuse a ground, but in this case it is the right thing to do.)

Check for a bad ground.

You can temporarily “rewire” by using an ordinary jumper cable across the two ACR terminals. (Just one wire from the jumper cable pair, of course.) Most chargers will not be damaged by another source pushing the voltage higher. The “three-stage” behavior may get confused, but that is not permanent.

You can place an ordinary DC multimeter on the two main terminals for the ACR. If it is working (combining) the voltage difference should be less than about 0.02 volts.

I have used the Blue Sea ACRs for many years. The only failure was due to a direct lightning strike.

[Gene Fuller]

I have always refilled mine, but I do not believe a small gap will hurt. I think it will fill itself over time.

The simple solution is to fill with the squeeze bulb before you put the top back on the Racor. Carefully, of course.

[Gene Fuller]

The first three images show mounts that are not collapsed, and they don’t look bad at all. The last image obviously has a significant problem with the rubber portion.

I would replace at least the pair (fore or aft) that has the bad mount.

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Robert Greig

[Gene Fuller]

The standard power requirement curve says that the power (and fuel burn) needed is directly related to the RPM raised to some exponential factor. Cummins uses 2.7 for the exponential factor.

I analyzed the Cat specs in your first post, and it is clear in that case the exponential factor is 3.0.

So, yes, the factory specs are different. The Cat spec is a bit more restrictive at mid-range RPMs.

However, that is irrelevant for either Cummins or Cat.

Specs are specs. The engine could be designed for almost anything, but it was actually designed to meet the published spec. Either stay within or you are over-propped.

Whether that actually causes a problem is not something I can address.

[Gene Fuller]

He was burning 34 GPH (17 gph per motor) at 2600 rpm

The Cummins spec for that engine is 12.7 gph at 2600 rpm.

[Author]

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